Commit graph

28792 commits

Author SHA1 Message Date
Mauricio Vasquez B c9d29f4658 bpf/syscall: allow key to be null in map functions
This commit adds the required logic to allow key being NULL
in case the key_size of the map is 0.

A new __bpf_copy_key function helper only copies the key from
userpsace when key_size != 0, otherwise it enforces that key must be
null.

Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-19 13:24:31 -07:00
Mauricio Vasquez B 144991602e bpf: rename stack trace map operations
In the following patches queue and stack maps (FIFO and LIFO
datastructures) will be implemented.  In order to avoid confusion and
a possible name clash rename stack_map_ops to stack_trace_map_ops

Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-19 13:24:30 -07:00
David S. Miller 2e2d6f0342 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
net/sched/cls_api.c has overlapping changes to a call to
nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL
to the 5th argument, and another (from 'net-next') added cb->extack
instead of NULL to the 6th argument.

net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to
code which moved (to mr_table_dump)) in 'net-next'.  Thanks to David
Ahern for the heads up.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-19 11:03:06 -07:00
Lukas Wunner 746a923b86 genirq: Fix race on spurious interrupt detection
Commit 1e77d0a1ed ("genirq: Sanitize spurious interrupt detection of
threaded irqs") made detection of spurious interrupts work for threaded
handlers by:

a) incrementing a counter every time the thread returns IRQ_HANDLED, and
b) checking whether that counter has increased every time the thread is
   woken.

However for oneshot interrupts, the commit unmasks the interrupt before
incrementing the counter.  If another interrupt occurs right after
unmasking but before the counter is incremented, that interrupt is
incorrectly considered spurious:

time
 |  irq_thread()
 |    irq_thread_fn()
 |      action->thread_fn()
 |      irq_finalize_oneshot()
 |        unmask_threaded_irq()            /* interrupt is unmasked */
 |
 |                  /* interrupt fires, incorrectly deemed spurious */
 |
 |    atomic_inc(&desc->threads_handled); /* counter is incremented */
 v

This is observed with a hi3110 CAN controller receiving data at high volume
(from a separate machine sending with "cangen -g 0 -i -x"): The controller
signals a huge number of interrupts (hundreds of millions per day) and
every second there are about a dozen which are deemed spurious.

In theory with high CPU load and the presence of higher priority tasks, the
number of incorrectly detected spurious interrupts might increase beyond
the 99,900 threshold and cause disablement of the interrupt.

In practice it just increments the spurious interrupt count. But that can
cause people to waste time investigating it over and over.

Fix it by moving the accounting before the invocation of
irq_finalize_oneshot().

[ tglx: Folded change log update ]

Fixes: 1e77d0a1ed ("genirq: Sanitize spurious interrupt detection of threaded irqs")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Akshay Bhat <akshay.bhat@timesys.com>
Cc: Casey Fitzpatrick <casey.fitzpatrick@timesys.com>
Cc: stable@vger.kernel.org # v3.16+
Link: https://lkml.kernel.org/r/1dfd8bbd16163940648045495e3e9698e63b50ad.1539867047.git.lukas@wunner.de
2018-10-19 17:31:00 +02:00
Greg Kroah-Hartman 91b15613ce Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
David writes:
  "Networking

   1) Fix gro_cells leak in xfrm layer, from Li RongQing.

   2) BPF selftests change RLIMIT_MEMLOCK blindly, don't do that.  From
      Eric Dumazet.

   3) AF_XDP calls synchronize_net() under RCU lock, fix from Björn
      Töpel.

   4) Out of bounds packet access in _decode_session6(), from Alexei
      Starovoitov.

   5) Several ethtool bugs, where we copy a struct into the kernel twice
      and our validations of the values in the first copy can be
      invalidated by the second copy due to asynchronous updates to the
      memory by the user.  From Wenwen Wang.

   6) Missing netlink attribute validation in cls_api, from Davide
      Caratti.

   7) LLC SAP sockets neet to be SOCK_RCU FREE, from Cong Wang.

   8) rxrpc operates on wrong kvec, from Yue Haibing.

   9) A regression was introduced by the disassosciation of route
      neighbour references in rt6_probe(), causing probe for
      neighbourless routes to not be properly rate limited.  Fix from
      Sabrina Dubroca.

   10) Unsafe RCU locking in tipc, from Tung Nguyen.

   11) Use after free in inet6_mc_check(), from Eric Dumazet.

   12) PMTU from icmp packets should update the SCTP transport pathmtu,
       from Xin Long.

   13) Missing peer put on error in rxrpc, from David Howells.

   14) Fix pedit in nfp driver, from Pieter Jansen van Vuuren.

   15) Fix overflowing shift statement in qla3xxx driver, from Nathan
       Chancellor.

   16) Fix Spectre v1 in ptp code, from Gustavo A. R. Silva.

   17) udp6_unicast_rcv_skb() interprets udpv6_queue_rcv_skb() return
       value in an inverted manner, fix from Paolo Abeni.

   18) Fix missed unresolved entries in ipmr dumps, from Nikolay
       Aleksandrov.

   19) Fix NAPI handling under high load, we can completely miss events
       when NAPI has to loop more than one time in a cycle.  From Heiner
       Kallweit."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (49 commits)
  ip6_tunnel: Fix encapsulation layout
  tipc: fix info leak from kernel tipc_event
  net: socket: fix a missing-check bug
  net: sched: Fix for duplicate class dump
  r8169: fix NAPI handling under high load
  net: ipmr: fix unresolved entry dumps
  net: mscc: ocelot: Fix comment in ocelot_vlant_wait_for_completion()
  sctp: fix the data size calculation in sctp_data_size
  virtio_net: avoid using netif_tx_disable() for serializing tx routine
  udp6: fix encap return code for resubmitting
  mlxsw: core: Fix use-after-free when flashing firmware during init
  sctp: not free the new asoc when sctp_wait_for_connect returns err
  sctp: fix race on sctp_id2asoc
  r8169: re-enable MSI-X on RTL8168g
  net: bpfilter: use get_pid_task instead of pid_task
  ptp: fix Spectre v1 vulnerability
  net: qla3xxx: Remove overflowing shift statement
  geneve, vxlan: Don't set exceptions if skb->len < mtu
  geneve, vxlan: Don't check skb_dst() twice
  sctp: get pr_assoc and pr_stream all status with SCTP_PR_SCTP_ALL instead
  ...
2018-10-19 09:16:20 +02:00
Christoph Hellwig a4a4330db4 swiotlb: add support for non-coherent DMA
Handle architectures that are not cache coherent directly in the main
swiotlb code by calling arch_sync_dma_for_{device,cpu} in all the right
places from the various dma_map/unmap/sync methods when the device is
non-coherent.

Because swiotlb now uses dma_direct_alloc for the coherent allocation
that side is already taken care of by the dma-direct code calling into
arch_dma_{alloc,free} for devices that are non-coherent.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-10-19 08:53:05 +02:00
Christoph Hellwig fafadcd165 swiotlb: don't dip into swiotlb pool for coherent allocations
All architectures that support swiotlb also have a zone that backs up
these less than full addressing allocations (usually ZONE_DMA32).

Because of that it is rather pointless to fall back to the global swiotlb
buffer if the normal dma direct allocation failed - the only thing this
will do is to eat up bounce buffers that would be more useful to serve
streaming mappings.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-10-19 08:48:28 +02:00
Christoph Hellwig c4dae36692 swiotlb: refactor swiotlb_map_page
Remove the somewhat useless map_single function, and replace it with a
swiotlb_bounce_page handler that handles everything related to actually
bouncing a page.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-10-19 08:46:58 +02:00
Christoph Hellwig 4803b44e68 swiotlb: use swiotlb_map_page in swiotlb_map_sg_attrs
No need to duplicate the code - map_sg is equivalent to map_page
for each page in the scatterlist.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-10-19 08:44:39 +02:00
Christoph Hellwig 27744e0077 swiotlb: merge swiotlb_unmap_page and unmap_single
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-10-19 08:44:16 +02:00
Christoph Hellwig dff8d6c1ed swiotlb: remove the overflow buffer
Like all other dma mapping drivers just return an error code instead
of an actual memory buffer.  The reason for the overflow buffer was
that at the time swiotlb was invented there was no way to check for
dma mapping errors, but this has long been fixed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-10-19 08:43:46 +02:00
Christoph Hellwig 8088546832 swiotlb: do not panic on mapping failures
All properly written drivers now have error handling in the
dma_map_single / dma_map_page callers.  As swiotlb_tbl_map_single already
prints a useful warning when running out of swiotlb pool space we can
also remove swiotlb_full entirely as it serves no purpose now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-10-19 08:43:04 +02:00
Christoph Hellwig b65125c6ac swiotlb: mark is_swiotlb_buffer static
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-10-19 08:42:39 +02:00
Christoph Hellwig 21bb9d64c5 swiotlb: remove a pointless comment
This comments describes an aspect of the map_sg interface that isn't
even exploited by swiotlb.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-10-19 08:42:20 +02:00
Waiman Long 9506a7425b locking/lockdep: Fix debug_locks off performance problem
It was found that when debug_locks was turned off because of a problem
found by the lockdep code, the system performance could drop quite
significantly when the lock_stat code was also configured into the
kernel. For instance, parallel kernel build time on a 4-socket x86-64
server nearly doubled.

Further analysis into the cause of the slowdown traced back to the
frequent call to debug_locks_off() from the __lock_acquired() function
probably due to some inconsistent lockdep states with debug_locks
off. The debug_locks_off() function did an unconditional atomic xchg
to write a 0 value into debug_locks which had already been set to 0.
This led to severe cacheline contention in the cacheline that held
debug_locks.  As debug_locks is being referenced in quite a few different
places in the kernel, this greatly slow down the system performance.

To prevent that trashing of debug_locks cacheline, lock_acquired()
and lock_contended() now checks the state of debug_locks before
proceeding. The debug_locks_off() function is also modified to check
debug_locks before calling __debug_locks_off().

Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1539913518-15598-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-19 07:53:17 +02:00
Yangtao Li e45506ac0a softirq: Fix typo in __do_softirq() comments
s/s/as

[ mingo: Also add a missing 'the', add proper punctuation and clarify what 'swap' means here. ]

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: alexander.levin@verizon.com
Cc: frederic@kernel.org
Cc: joel@joelfernandes.org
Cc: paulmck@linux.vnet.ibm.com
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/20181018142133.12341-1-tiny.windzz@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-18 18:10:23 +02:00
Rafael J. Wysocki 3f858ae02c Merge branches 'acpi-pm' and 'pm-sleep'
* acpi-pm:
  ACPI / PM: LPIT: Register sysfs attributes based on FADT

* pm-sleep:
  x86-32, hibernate: Adjust in_suspend after resumed on 32bit system
  x86-32, hibernate: Set up temporary text mapping for 32bit system
  x86-32, hibernate: Switch to relocated restore code during resume on 32bit system
  x86-32, hibernate: Switch to original page table after resumed
  x86-32, hibernate: Use the page size macro instead of constant value
  x86-32, hibernate: Use temp_pgt as the temporary page table
  x86, hibernate: Rename temp_level4_pgt to temp_pgt
  x86-32, hibernate: Enable CONFIG_ARCH_HIBERNATION_HEADER on 32bit system
  x86, hibernate: Extract the common code of 64/32 bit system
  x86-32/asm/power: Create stack frames in hibernate_asm_32.S
  PM / hibernate: Check the success of generating md5 digest before hibernation
  x86, hibernate: Fix nosave_regions setup for hibernation
  PM / sleep: Show freezing tasks that caused a suspend abort
  PM / hibernate: Documentation: fix image_size default value
2018-10-18 12:27:30 +02:00
Greg Kroah-Hartman 9bd871df56 This fixes two bugs:
- Fix size mismatch of tracepoint array
 
  - Have preemptirq test module use same clock source of the selftest
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Merge tag 'trace-v4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Steven writes:
  "tracing: Two fixes for 4.19

   This fixes two bugs:
    - Fix size mismatch of tracepoint array
    - Have preemptirq test module use same clock source of the selftest"

* tag 'trace-v4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Use trace_clock_local() for looping in preemptirq_delay_test.c
  tracepoint: Fix tracepoint array element size mismatch
2018-10-18 07:29:05 +02:00
Steven Rostedt (VMware) 12ad0cb212 tracing: Use trace_clock_local() for looping in preemptirq_delay_test.c
The preemptirq_delay_test module is used for the ftrace selftest code that
tests the latency tracers. The problem is that it uses ktime for the delay
loop, and then checks the tracer to see if the delay loop is caught, but the
tracer uses trace_clock_local() which uses various different other clocks to
measure the latency. As ktime uses the clock cycles, and the code then
converts that to nanoseconds, it causes rounding errors, and the preemptirq
latency tests are failing due to being off by 1 (it expects to see a delay
of 500000 us, but the delay is only 499999 us). This is happening due to a
rounding error in the ktime (which is totally legit). The purpose of the
test is to see if it can catch the delay, not to test the accuracy between
trace_clock_local() and ktime_get(). Best to use apples to apples, and have
the delay loop use the same clock as the latency tracer does.

Cc: stable@vger.kernel.org
Fixes: f96e8577da ("lib: Add module for testing preemptoff/irqsoff latency tracers")
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-17 15:35:33 -04:00
Mathieu Desnoyers 9c0be3f6b5 tracepoint: Fix tracepoint array element size mismatch
commit 46e0c9be20 ("kernel: tracepoints: add support for relative
references") changes the layout of the __tracepoint_ptrs section on
architectures supporting relative references. However, it does so
without turning struct tracepoint * const into const int elsewhere in
the tracepoint code, which has the following side-effect:

Setting mod->num_tracepoints is done in by module.c:

    mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
                                         sizeof(*mod->tracepoints_ptrs),
                                         &mod->num_tracepoints);

Basically, since sizeof(*mod->tracepoints_ptrs) is a pointer size
(rather than sizeof(int)), num_tracepoints is erroneously set to half the
size it should be on 64-bit arch. So a module with an odd number of
tracepoints misses the last tracepoint due to effect of integer
division.

So in the module going notifier:

        for_each_tracepoint_range(mod->tracepoints_ptrs,
                mod->tracepoints_ptrs + mod->num_tracepoints,
                tp_module_going_check_quiescent, NULL);

the expression (mod->tracepoints_ptrs + mod->num_tracepoints) actually
evaluates to something within the bounds of the array, but miss the
last tracepoint if the number of tracepoints is odd on 64-bit arch.

Fix this by introducing a new typedef: tracepoint_ptr_t, which
is either "const int" on architectures that have PREL32 relocations,
or "struct tracepoint * const" on architectures that does not have
this feature.

Also provide a new tracepoint_ptr_defer() static inline to
encapsulate deferencing this type rather than duplicate code and
ugly idefs within the for_each_tracepoint_range() implementation.

This issue appears in 4.19-rc kernels, and should ideally be fixed
before the end of the rc cycle.

Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Link: http://lkml.kernel.org/r/20181013191050.22389-1-mathieu.desnoyers@efficios.com
Link: http://lkml.kernel.org/r/20180704083651.24360-7-ard.biesheuvel@linaro.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morris <james.morris@microsoft.com>
Cc: James Morris <jmorris@namei.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-17 15:35:29 -04:00
Waiman Long 0fa809ca7f locking/pvqspinlock: Extend node size when pvqspinlock is configured
The qspinlock code supports up to 4 levels of slowpath nesting using
four per-CPU mcs_spinlock structures. For 64-bit architectures, they
fit nicely in one 64-byte cacheline.

For para-virtualized (PV) qspinlocks it needs to store more information
in the per-CPU node structure than there is space for. It uses a trick
to use a second cacheline to hold the extra information that it needs.
So PV qspinlock needs to access two extra cachelines for its information
whereas the native qspinlock code only needs one extra cacheline.

Freshly added counter profiling of the qspinlock code, however, revealed
that it was very rare to use more than two levels of slowpath nesting.
So it doesn't make sense to penalize PV qspinlock code in order to have
four mcs_spinlock structures in the same cacheline to optimize for a case
in the native qspinlock code that rarely happens.

Extend the per-CPU node structure to have two more long words when PV
qspinlock locks are configured to hold the extra data that it needs.

As a result, the PV qspinlock code will enjoy the same benefit of using
just one extra cacheline like the native counterpart, for most cases.

[ mingo: Minor changelog edits. ]

Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1539697507-28084-2-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-17 08:37:32 +02:00
Waiman Long 1222109a53 locking/qspinlock_stat: Count instances of nested lock slowpaths
Queued spinlock supports up to 4 levels of lock slowpath nesting -
user context, soft IRQ, hard IRQ and NMI. However, we are not sure how
often the nesting happens.

So add 3 more per-CPU stat counters to track the number of instances where
nesting index goes to 1, 2 and 3 respectively.

On a dual-socket 64-core 128-thread Zen server, the following were the
new stat counter values under different circumstances:

         State                         slowpath   index1   index2   index3
         -----                         --------   ------   ------   -------
  After bootup                         1,012,150    82       0        0
  After parallel build + perf-top    125,195,009    82       0        0

So the chance of having more than 2 levels of nesting is extremely low.

[ mingo: Minor changelog edits. ]

Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1539697507-28084-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-17 08:37:31 +02:00
Peter Zijlstra 7aa54be297 locking/qspinlock, x86: Provide liveness guarantee
On x86 we cannot do fetch_or() with a single instruction and thus end up
using a cmpxchg loop, this reduces determinism. Replace the fetch_or()
with a composite operation: tas-pending + load.

Using two instructions of course opens a window we previously did not
have. Consider the scenario:

	CPU0		CPU1		CPU2

 1)	lock
	  trylock -> (0,0,1)

 2)			lock
			  trylock /* fail */

 3)	unlock -> (0,0,0)

 4)					lock
					  trylock -> (0,0,1)

 5)			  tas-pending -> (0,1,1)
			  load-val <- (0,1,0) from 3

 6)			  clear-pending-set-locked -> (0,0,1)

			  FAIL: _2_ owners

where 5) is our new composite operation. When we consider each part of
the qspinlock state as a separate variable (as we can when
_Q_PENDING_BITS == 8) then the above is entirely possible, because
tas-pending will only RmW the pending byte, so the later load is able
to observe prior tail and lock state (but not earlier than its own
trylock, which operates on the whole word, due to coherence).

To avoid this we need 2 things:

 - the load must come after the tas-pending (obviously, otherwise it
   can trivially observe prior state).

 - the tas-pending must be a full word RmW instruction, it cannot be an XCHGB for
   example, such that we cannot observe other state prior to setting
   pending.

On x86 we can realize this by using "LOCK BTS m32, r32" for
tas-pending followed by a regular load.

Note that observing later state is not a problem:

 - if we fail to observe a later unlock, we'll simply spin-wait for
   that store to become visible.

 - if we observe a later xchg_tail(), there is no difference from that
   xchg_tail() having taken place before the tas-pending.

Suggested-by: Will Deacon <will.deacon@arm.com>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: andrea.parri@amarulasolutions.com
Cc: longman@redhat.com
Fixes: 59fb586b4a ("locking/qspinlock: Remove unbounded cmpxchg() loop from locking slowpath")
Link: https://lkml.kernel.org/r/20181003130957.183726335@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16 17:33:54 +02:00
Peter Zijlstra 756b1df4c2 locking/qspinlock: Rework some comments
While working my way through the code again; I felt the comments could
use help.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andrea.parri@amarulasolutions.com
Cc: longman@redhat.com
Link: https://lkml.kernel.org/r/20181003130257.156322446@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16 17:33:54 +02:00
Peter Zijlstra 53bf57fab7 locking/qspinlock: Re-order code
Flip the branch condition after atomic_fetch_or_acquire(_Q_PENDING_VAL)
such that we loose the indent. This also result in a more natural code
flow IMO.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andrea.parri@amarulasolutions.com
Cc: longman@redhat.com
Link: https://lkml.kernel.org/r/20181003130257.156322446@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16 17:33:53 +02:00
Ingo Molnar ec57e2f0ac Merge branch 'x86/build' into locking/core, to pick up dependent patches and unify jump-label work
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16 17:30:11 +02:00
Song Muchun 9845c49cc9 sched/fair: Fix the min_vruntime update logic in dequeue_entity()
The comment and the code around the update_min_vruntime() call in
dequeue_entity() are not in agreement.

From commit:

  b60205c7c5 ("sched/fair: Fix min_vruntime tracking")

I think that we want to update min_vruntime when a task is sleeping/migrating.
So, the check is inverted there - fix it.

Signed-off-by: Song Muchun <smuchun@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: b60205c7c5 ("sched/fair: Fix min_vruntime tracking")
Link: http://lkml.kernel.org/r/20181014112612.2614-1-smuchun@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16 09:36:01 +02:00
Waiman Long 4766ab5677 locking/lockdep: Remove duplicated 'lock_class_ops' percpu array
Remove the duplicated 'lock_class_ops' percpu array that is not used
anywhere.

Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Fixes: 8ca2b56cd7 ("locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y")
Link: http://lkml.kernel.org/r/1539380547-16726-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16 08:21:10 +02:00
David S. Miller e85679511e Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-10-16

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Convert BPF sockmap and kTLS to both use a new sk_msg API and enable
   sk_msg BPF integration for the latter, from Daniel and John.

2) Enable BPF syscall side to indicate for maps that they do not support
   a map lookup operation as opposed to just missing key, from Prashant.

3) Add bpftool map create command which after map creation pins the
   map into bpf fs for further processing, from Jakub.

4) Add bpftool support for attaching programs to maps allowing sock_map
   and sock_hash to be used from bpftool, from John.

5) Improve syscall BPF map update/delete path for map-in-map types to
   wait a RCU grace period for pending references to complete, from Daniel.

6) Couple of follow-up fixes for the BPF socket lookup to get it
   enabled also when IPv6 is compiled as a module, from Joe.

7) Fix a generic-XDP bug to handle the case when the Ethernet header
   was mangled and thus update skb's protocol and data, from Jesper.

8) Add a missing BTF header length check between header copies from
   user space, from Wenwen.

9) Minor fixups in libbpf to use __u32 instead u32 types and include
   proper perf_event.h uapi header instead of perf internal one, from Yonghong.

10) Allow to pass user-defined flags through EXTRA_CFLAGS and EXTRA_LDFLAGS
    to bpftool's build, from Jiri.

11) BPF kselftest tweaks to add LWTUNNEL to config fragment and to install
    with_addr.sh script from flow dissector selftest, from Anders.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15 23:21:07 -07:00
Daniel Borkmann 604326b41a bpf, sockmap: convert to generic sk_msg interface
Add a generic sk_msg layer, and convert current sockmap and later
kTLS over to make use of it. While sk_buff handles network packet
representation from netdevice up to socket, sk_msg handles data
representation from application to socket layer.

This means that sk_msg framework spans across ULP users in the
kernel, and enables features such as introspection or filtering
of data with the help of BPF programs that operate on this data
structure.

Latter becomes in particular useful for kTLS where data encryption
is deferred into the kernel, and as such enabling the kernel to
perform L7 introspection and policy based on BPF for TLS connections
where the record is being encrypted after BPF has run and came to
a verdict. In order to get there, first step is to transform open
coding of scatter-gather list handling into a common core framework
that subsystems can use.

The code itself has been split and refactored into three bigger
pieces: i) the generic sk_msg API which deals with managing the
scatter gather ring, providing helpers for walking and mangling,
transferring application data from user space into it, and preparing
it for BPF pre/post-processing, ii) the plain sock map itself
where sockets can be attached to or detached from; these bits
are independent of i) which can now be used also without sock
map, and iii) the integration with plain TCP as one protocol
to be used for processing L7 application data (later this could
e.g. also be extended to other protocols like UDP). The semantics
are the same with the old sock map code and therefore no change
of user facing behavior or APIs. While pursuing this work it
also helped finding a number of bugs in the old sockmap code
that we've fixed already in earlier commits. The test_sockmap
kselftest suite passes through fine as well.

Joint work with John.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15 12:23:19 -07:00
Daniel Borkmann 1243a51f6c tcp, ulp: remove ulp bits from sockmap
In order to prepare sockmap logic to be used in combination with kTLS
we need to detangle it from ULP, and further split it in later commits
into a generic API.

Joint work with John.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15 12:23:19 -07:00
David S. Miller 028c99fa91 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-10-14

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix xsk map update and delete operation to not call synchronize_net()
   but to piggy back on SOCK_RCU_FREE for sockets instead as we are not
   allowed to sleep under RCU, from Björn.

2) Do not change RLIMIT_MEMLOCK in reuseport_bpf selftest if the process
   already has unlimited RLIMIT_MEMLOCK, from Eric.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-14 13:01:20 -07:00
David S. Miller d864991b22 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were easy to resolve using immediate context mostly,
except the cls_u32.c one where I simply too the entire HEAD
chunk.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 21:38:46 -07:00
Daniel Colascione 1ae80cf319 bpf: wait for running BPF programs when updating map-in-map
The map-in-map frequently serves as a mechanism for atomic
snapshotting of state that a BPF program might record.  The current
implementation is dangerous to use in this way, however, since
userspace has no way of knowing when all programs that might have
retrieved the "old" value of the map may have completed.

This change ensures that map update operations on map-in-map map types
always wait for all references to the old map to drop before returning
to userspace.

Signed-off-by: Daniel Colascione <dancol@google.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12 19:32:19 -07:00
Greg Kroah-Hartman eb81bfb224 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Dmitry writes:
  "Input updates for v4.19-rc7

   - we added a few scheduling points into various input interfaces to
     ensure that large writes will not cause RCU stalls
   - fixed configuring PS/2 keyboards as wakeup devices on newer
     platforms
   - added a new Xbox gamepad ID."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: uinput - add a schedule point in uinput_inject_events()
  Input: evdev - add a schedule point in evdev_write()
  Input: mousedev - add a schedule point in mousedev_write()
  Input: i8042 - enable keyboard wakeups by default when s2idle is used
  Input: xpad - add support for Xbox1 PDP Camo series gamepad
2018-10-12 12:35:02 +02:00
Sergey Senozhatsky d2130e82e9 printk: fix integer overflow in setup_log_buf()
The way we calculate logbuf free space percentage overflows signed
integer:

	int free;

	free = __LOG_BUF_LEN - log_next_idx;
	pr_info("early log buf free: %u(%u%%)\n",
		free, (free * 100) / __LOG_BUF_LEN);

We support LOG_BUF_LEN of up to 1<<25 bytes. Since setup_log_buf() is
called during early init, logbuf is mostly empty, so

	__LOG_BUF_LEN - log_next_idx

is close to 1<<25. Thus when we multiply it by 100, we overflow signed
integer value range: 100 is 2^6 + 2^5 + 2^2.

Example, booting with LOG_BUF_LEN 1<<25 and log_buf_len=2G
boot param:

[    0.075317] log_buf_len: -2147483648 bytes
[    0.075319] early log buf free: 33549896(-28%)

Make "free" unsigned integer and use appropriate printk() specifier.

Link: http://lkml.kernel.org/r/20181010113308.9337-1-sergey.senozhatsky@gmail.com
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12 10:44:17 +02:00
Sergey Senozhatsky 0e96a19c44 printk: do not preliminary split up cont buffer
We have a proper 'overflow' check which tells us that we need to
split up existing cont buffer in separate records:

	if (cont.len + len > sizeof(cont.buf))
		cont_flush();

At the same time we also have one extra flush: "if cont buffer is
80% full then split it up" in cont_add():

	if (cont.len > (sizeof(cont.buf) * 80) / 100)
		cont_flush();

This looks to be redundant, since the existing "overflow" check
should work just fine, so remove this 80% check and wait for either
a normal cont termination \n, for preliminary flush due to
possible buffer overflow or for preliminary flush due to cont race.

Link: http://lkml.kernel.org/r/20181002023836.4487-4-sergey.senozhatsky@gmail.com
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12 10:03:39 +02:00
Sergey Senozhatsky 3ac37a93fa printk: lock/unlock console only for new logbuf entries
Prior to commit 5c2992ee7f ("printk: remove console flushing special
cases for partial buffered lines") we would do console_cont_flush()
for each pr_cont() to print cont fragments, so console_unlock() would
actually print data:

	pr_cont();
	 console_lock();
	 console_unlock()
	  console_cont_flush(); // print cont fragment
	...
	pr_cont();
	 console_lock();
	 console_unlock()
	  console_cont_flush(); // print cont fragment

We don't do console_cont_flush() anymore, so when we do pr_cont()
console_unlock() does nothing (unless we flushed the cont buffer):

	pr_cont();
	 console_lock();
	 console_unlock();      // noop
	...
	pr_cont();
	 console_lock();
	 console_unlock();      // noop
	...
	pr_cont();
	  cont_flush();
	    console_lock();
	    console_unlock();   // print data

We also wakeup klogd purposelessly for pr_cont() output - un-flushed
cont buffer is not stored in log_buf; there is nothing to pull.

Thus we can console_lock()/console_unlock()/wake_up_klogd() only when
we know that we log_store()-ed a message and there is something to
print to the consoles/syslog.

Link: http://lkml.kernel.org/r/20181002023836.4487-3-sergey.senozhatsky@gmail.com
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12 10:03:39 +02:00
Sergey Senozhatsky 9627808d2d printk: keep kernel cont support always enabled
Since commit 5c2992ee7f ("printk: remove console flushing special
cases for partial buffered lines") we don't print cont fragments
to the consoles; cont lines are now proper log_buf entries and
there is no "consecutive continuation flag" anymore: we either
have 'c' entries that mark continuation lines without fragments;
or '-' entries that mark normal logbuf entries. There are no '+'
entries anymore.

However, we still have a small leftover - presence of ext_console
drivers disables kernel cont support and we flush each pr_cont()
and store it as a separate log_buf entry. Previously, it worked
because msg_print_ext_header() had that "an optional external merge
of the records" functionality:

	if (msg->flags & LOG_CONT)
		cont = (prev_flags & LOG_CONT) ? '+' : 'c';

We don't do this as of now, so keep kernel cont always enabled.

Note from pmladek:

The original purpose was to get full information including
the metadata and dictionary via extended console drivers,
see commit 6fe29354be ("printk: implement support
for extended console drivers").

The dictionary probably was the most important part but
it was actually lost:

  static void cont_flush(void)
  {
  [...]
	log_store(cont.facility, cont.level, cont.flags, cont.ts_nsec,
		  NULL, 0, cont.buf, cont.len);

Nobody noticed because the only dictionary user is dev_printk()
and dev_cont() is _not_ defined.

Link: http://lkml.kernel.org/r/20181002023836.4487-2-sergey.senozhatsky@gmail.com
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
[pmladek@suse.com: Updated commit message]
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12 10:03:30 +02:00
Greg Kroah-Hartman 0778a9f2dd Merge branch 'for-4.19-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Tejun writes:
  "cgroup fixes for v4.19-rc7

   One cgroup2 threaded mode fix for v4.19-rc7.  While threaded mode
   isn't used widely (yet) and the bug requires somewhat convoluted
   sequence of operations, it causes a userland visible malfunction -
   EINVAL on a valid attempt to enable threaded mode.  This pull request
   contains the fix"

* 'for-4.19-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: Fix dom_cgrp propagation when enabling threaded mode
2018-10-11 19:24:01 +02:00
Phil Auld baa9be4ffb sched/fair: Fix throttle_list starvation with low CFS quota
With a very low cpu.cfs_quota_us setting, such as the minimum of 1000,
distribute_cfs_runtime may not empty the throttled_list before it runs
out of runtime to distribute. In that case, due to the change from
c06f04c704 to put throttled entries at the head of the list, later entries
on the list will starve.  Essentially, the same X processes will get pulled
off the list, given CPU time and then, when expired, get put back on the
head of the list where distribute_cfs_runtime will give runtime to the same
set of processes leaving the rest.

Fix the issue by setting a bit in struct cfs_bandwidth when
distribute_cfs_runtime is running, so that the code in throttle_cfs_rq can
decide to put the throttled entry on the tail or the head of the list.  The
bit is set/cleared by the callers of distribute_cfs_runtime while they hold
cfs_bandwidth->lock.

This is easy to reproduce with a handful of CPU consumers. I use 'crash' on
the live system. In some cases you can simply look at the throttled list and
see the later entries are not changing:

  crash> list cfs_rq.throttled_list -H 0xffff90b54f6ade40 -s cfs_rq.runtime_remaining | paste - - | awk '{print $1"  "$4}' | pr -t -n3
    1     ffff90b56cb2d200  -976050
    2     ffff90b56cb2cc00  -484925
    3     ffff90b56cb2bc00  -658814
    4     ffff90b56cb2ba00  -275365
    5     ffff90b166a45600  -135138
    6     ffff90b56cb2da00  -282505
    7     ffff90b56cb2e000  -148065
    8     ffff90b56cb2fa00  -872591
    9     ffff90b56cb2c000  -84687
   10     ffff90b56cb2f000  -87237
   11     ffff90b166a40a00  -164582

  crash> list cfs_rq.throttled_list -H 0xffff90b54f6ade40 -s cfs_rq.runtime_remaining | paste - - | awk '{print $1"  "$4}' | pr -t -n3
    1     ffff90b56cb2d200  -994147
    2     ffff90b56cb2cc00  -306051
    3     ffff90b56cb2bc00  -961321
    4     ffff90b56cb2ba00  -24490
    5     ffff90b166a45600  -135138
    6     ffff90b56cb2da00  -282505
    7     ffff90b56cb2e000  -148065
    8     ffff90b56cb2fa00  -872591
    9     ffff90b56cb2c000  -84687
   10     ffff90b56cb2f000  -87237
   11     ffff90b166a40a00  -164582

Sometimes it is easier to see by finding a process getting starved and looking
at the sched_info:

  crash> task ffff8eb765994500 sched_info
  PID: 7800   TASK: ffff8eb765994500  CPU: 16  COMMAND: "cputest"
    sched_info = {
      pcount = 8,
      run_delay = 697094208,
      last_arrival = 240260125039,
      last_queued = 240260327513
    },
  crash> task ffff8eb765994500 sched_info
  PID: 7800   TASK: ffff8eb765994500  CPU: 16  COMMAND: "cputest"
    sched_info = {
      pcount = 8,
      run_delay = 697094208,
      last_arrival = 240260125039,
      last_queued = 240260327513
    },

Signed-off-by: Phil Auld <pauld@redhat.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: c06f04c704 ("sched: Fix potential near-infinite distribute_cfs_runtime() loop")
Link: http://lkml.kernel.org/r/20181008143639.GA4019@pauld.bos.csb
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-11 13:10:18 +02:00
Björn Töpel cee271678d xsk: do not call synchronize_net() under RCU read lock
The XSKMAP update and delete functions called synchronize_net(), which
can sleep. It is not allowed to sleep during an RCU read section.

Instead we need to make sure that the sock sk_destruct (xsk_destruct)
function is asynchronously called after an RCU grace period. Setting
the SOCK_RCU_FREE flag for XDP sockets takes care of this.

Fixes: fbfc504a24 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-11 10:19:01 +02:00
Eric W. Biederman a36700589b signal: Guard against negative signal numbers in copy_siginfo_from_user32
While fixing an out of bounds array access in known_siginfo_layout
reported by the kernel test robot it became apparent that the same bug
exists in siginfo_layout and affects copy_siginfo_from_user32.

The straight forward fix that makes guards against making this mistake
in the future and should keep the code size small is to just take an
unsigned signal number instead of a signed signal number, as I did to
fix known_siginfo_layout.

Cc: stable@vger.kernel.org
Fixes: cc731525f2 ("signal: Remove kernel interal si_code magic")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-10 20:34:14 -05:00
Eric W. Biederman b2a2ab527d signal: Guard against negative signal numbers in copy_siginfo_from_user
The bounds checks in known_siginfo_layout only guards against positive
numbers that are too large, large negative can slip through and
can cause out of bounds accesses.

Ordinarily this is not a concern because early in signal processing
the signal number is filtered with valid_signal which ensures it
is a small positive signal number, but copy_siginfo_from_user
is called before this check is performed.

[   73.031126] BUG: unable to handle kernel paging request at ffffffff6281bcb6
[   73.032038] PGD 3014067 P4D 3014067 PUD 0
[   73.032565] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
[   73.033287] CPU: 0 PID: 732 Comm: trinity-c3 Tainted: G        W       T 4.19.0-rc1-00077-g4ce5f9c #1
[   73.034423] RIP: 0010:copy_siginfo_from_user+0x4d/0xd0
[   73.034908] Code: 00 8b 53 08 81 fa 80 00 00 00 0f 84 90 00 00 00 85 d2 7e 2d 48 63 0b 83 f9 1f 7f 1c 8d 71 ff bf d8 04 01 50 48 0f a3 f7 73 0e <0f> b6 8c 09 20 bb 81 82 39 ca 7f 15 eb 68 31 c0 83 fa 06 7f 0c eb
[   73.036665] RSP: 0018:ffff88001b8f7e20 EFLAGS: 00010297
[   73.037160] RAX: 0000000000000000 RBX: ffff88001b8f7e90 RCX: fffffffff00000cb
[   73.037865] RDX: 0000000000000001 RSI: 00000000f00000ca RDI: 00000000500104d8
[   73.038546] RBP: ffff88001b8f7e80 R08: 0000000000000000 R09: 0000000000000000
[   73.039201] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000008
[   73.039874] R13: 00000000000002dc R14: 0000000000000000 R15: 0000000000000000
[   73.040613] FS:  000000000104a880(0000) GS:ffff88001f000000(0000) knlGS:0000000000000000
[   73.041649] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   73.042405] CR2: ffffffff6281bcb6 CR3: 000000001cb52003 CR4: 00000000001606b0
[   73.043351] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   73.044286] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
[   73.045221] Call Trace:
[   73.045556]  __x64_sys_rt_tgsigqueueinfo+0x34/0xa0
[   73.046199]  do_syscall_64+0x1a4/0x390
[   73.046708]  ? vtime_user_enter+0x61/0x80
[   73.047242]  ? __context_tracking_enter+0x4e/0x60
[   73.047714]  ? __context_tracking_enter+0x4e/0x60
[   73.048278]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Therefore fix known_siginfo_layout to take an unsigned signal number
instead of a signed signal number.  All valid signal numbers are small
positive numbers so they will not be affected, but invalid negative
signal numbers will now become large positive signal numbers and will
not be used as indices into the sig_sicodes array.

Making the signal number unsigned makes it difficult for similar mistakes to
happen in the future.

Fixes: 4ce5f9c9e7 ("signal: Use a smaller struct siginfo in the kernel")
Inspired-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-10 20:28:33 -05:00
Peng Hao d59e0ba194 tick/sched : Remove redundant cpu_online() check
can_stop_idle_tick() checks cpu_online() twice. The first check leaves the
function when the CPU is not online, so the second check it
redundant. Remove it.

Signed-off-by: Peng Hao <peng.hao2@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: fweisbec@gmail.com
Link: https://lkml.kernel.org/r/1539099815-2943-1-git-send-email-penghao122@sina.com.cn
2018-10-10 11:47:20 +02:00
Prashant Bhole 3b4a63f674 bpf: return EOPNOTSUPP when map lookup isn't supported
Return ERR_PTR(-EOPNOTSUPP) from map_lookup_elem() methods of below
map types:
- BPF_MAP_TYPE_PROG_ARRAY
- BPF_MAP_TYPE_STACK_TRACE
- BPF_MAP_TYPE_XSKMAP
- BPF_MAP_TYPE_SOCKMAP/BPF_MAP_TYPE_SOCKHASH

Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-09 21:52:20 -07:00
Prashant Bhole 509db2833e bpf: error handling when map_lookup_elem isn't supported
The error value returned by map_lookup_elem doesn't differentiate
whether lookup was failed because of invalid key or lookup is not
supported.

Lets add handling for -EOPNOTSUPP return value of map_lookup_elem()
method of map, with expectation from map's implementation that it
should return -EOPNOTSUPP if lookup is not supported.

The errno for bpf syscall for BPF_MAP_LOOKUP_ELEM command will be set
to EOPNOTSUPP if map lookup is not supported.

Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-09 21:52:20 -07:00
Wenwen Wang 8af03d1ae2 bpf: btf: Fix a missing check bug
In btf_parse_hdr(), the length of the btf data header is firstly copied
from the user space to 'hdr_len' and checked to see whether it is larger
than 'btf_data_size'. If yes, an error code EINVAL is returned. Otherwise,
the whole header is copied again from the user space to 'btf->hdr'.
However, after the second copy, there is no check between
'btf->hdr->hdr_len' and 'hdr_len' to confirm that the two copies get the
same value. Given that the btf data is in the user space, a malicious user
can race to change the data between the two copies. By doing so, the user
can provide malicious data to the kernel and cause undefined behavior.

This patch adds a necessary check after the second copy, to make sure
'btf->hdr->hdr_len' has the same value as 'hdr_len'. Otherwise, an error
code EINVAL will be returned.

Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-09 21:42:51 -07:00
Borislav Petkov b69c2e20f6 resource: Clean it up a bit
- Drop BUG_ON()s and do normal error handling instead, in
  find_next_iomem_res().

- Align function arguments on opening braces.

- Get rid of local var sibling_only in find_next_iomem_res().

- Shorten unnecessarily long first_level_children_only arg name.

Signed-off-by: Borislav Petkov <bp@suse.de>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Brijesh Singh <brijesh.singh@amd.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Lianbo Jiang <lijiang@redhat.com>
CC: Takashi Iwai <tiwai@suse.de>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tom Lendacky <thomas.lendacky@amd.com>
CC: Vivek Goyal <vgoyal@redhat.com>
CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
CC: bhe@redhat.com
CC: dan.j.williams@intel.com
CC: dyoung@redhat.com
CC: kexec@lists.infradead.org
CC: mingo@redhat.com
Link: <new submission>
2018-10-09 17:25:58 +02:00
Bjorn Helgaas 010a93bf97 resource: Fix find_next_iomem_res() iteration issue
Previously find_next_iomem_res() used "*res" as both an input parameter for
the range to search and the type of resource to search for, and an output
parameter for the resource we found, which makes the interface confusing.

The current callers use find_next_iomem_res() incorrectly because they
allocate a single struct resource and use it for repeated calls to
find_next_iomem_res().  When find_next_iomem_res() returns a resource, it
overwrites the start, end, flags, and desc members of the struct.  If we
call find_next_iomem_res() again, we must update or restore these fields.
The previous code restored res.start and res.end, but not res.flags or
res.desc.

Since the callers did not restore res.flags, if they searched for flags
IORESOURCE_MEM | IORESOURCE_BUSY and found a resource with flags
IORESOURCE_MEM | IORESOURCE_BUSY | IORESOURCE_SYSRAM, the next search would
incorrectly skip resources unless they were also marked as
IORESOURCE_SYSRAM.

Fix this by restructuring the interface so it takes explicit "start, end,
flags" parameters and uses "*res" only as an output parameter.

Based on a patch by Lianbo Jiang <lijiang@redhat.com>.

 [ bp: While at it:
   - make comments kernel-doc style.
   -

Originally-by: http://lore.kernel.org/lkml/20180921073211.20097-2-lijiang@redhat.com
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Brijesh Singh <brijesh.singh@amd.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Lianbo Jiang <lijiang@redhat.com>
CC: Takashi Iwai <tiwai@suse.de>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tom Lendacky <thomas.lendacky@amd.com>
CC: Vivek Goyal <vgoyal@redhat.com>
CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
CC: bhe@redhat.com
CC: dan.j.williams@intel.com
CC: dyoung@redhat.com
CC: kexec@lists.infradead.org
CC: mingo@redhat.com
CC: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/153805812916.1157.177580438135143788.stgit@bhelgaas-glaptop.roam.corp.google.com
2018-10-09 17:18:36 +02:00
Bjorn Helgaas a98959fdbd resource: Include resource end in walk_*() interfaces
find_next_iomem_res() finds an iomem resource that covers part of a range
described by "start, end".  All callers expect that range to be inclusive,
i.e., both start and end are included, but find_next_iomem_res() doesn't
handle the end address correctly.

If it finds an iomem resource that contains exactly the end address, it
skips it, e.g., if "start, end" is [0x0-0x10000] and there happens to be an
iomem resource [mem 0x10000-0x10000] (the single byte at 0x10000), we skip
it:

  find_next_iomem_res(...)
  {
    start = 0x0;
    end = 0x10000;
    for (p = next_resource(...)) {
      # p->start = 0x10000;
      # p->end = 0x10000;
      # we *should* return this resource, but this condition is false:
      if ((p->end >= start) && (p->start < end))
        break;

Adjust find_next_iomem_res() so it allows a resource that includes the
single byte at the end of the range.  This is a corner case that we
probably don't see in practice.

Fixes: 58c1b5b079 ("[PATCH] memory hotadd fixes: find_next_system_ram catch range fix")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Brijesh Singh <brijesh.singh@amd.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Lianbo Jiang <lijiang@redhat.com>
CC: Takashi Iwai <tiwai@suse.de>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Tom Lendacky <thomas.lendacky@amd.com>
CC: Vivek Goyal <vgoyal@redhat.com>
CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
CC: bhe@redhat.com
CC: dan.j.williams@intel.com
CC: dyoung@redhat.com
CC: kexec@lists.infradead.org
CC: mingo@redhat.com
CC: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/153805812254.1157.16736368485811773752.stgit@bhelgaas-glaptop.roam.corp.google.com
2018-10-09 17:18:34 +02:00
Rik van Riel 7d49b28a80 smp,cpumask: introduce on_each_cpu_cond_mask
Introduce a variant of on_each_cpu_cond that iterates only over the
CPUs in a cpumask, in order to avoid making callbacks for every single
CPU in the system when we only need to test a subset.

Cc: npiggin@gmail.com
Cc: mingo@kernel.org
Cc: will.deacon@arm.com
Cc: songliubraving@fb.com
Cc: kernel-team@fb.com
Cc: hpa@zytor.com
Cc: luto@kernel.org
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180926035844.1420-5-riel@surriel.com
2018-10-09 16:51:11 +02:00
Rik van Riel c3f7f2c7eb smp: use __cpumask_set_cpu in on_each_cpu_cond
The code in on_each_cpu_cond sets CPUs in a locally allocated bitmask,
which should never be used by other CPUs simultaneously. There is no
need to use locked memory accesses to set the bits in this bitmap.

Switch to __cpumask_set_cpu.

Cc: npiggin@gmail.com
Cc: mingo@kernel.org
Cc: will.deacon@arm.com
Cc: songliubraving@fb.com
Cc: kernel-team@fb.com
Cc: hpa@zytor.com
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180926035844.1420-4-riel@surriel.com
2018-10-09 16:51:11 +02:00
Christoph Hellwig b9fd04262a dma-direct: respect DMA_ATTR_NO_WARN
Respect the DMA_ATTR_NO_WARN flags for allocations in dma-direct.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Robin Murphy <robin.murphy@arm.com>
2018-10-09 15:08:46 +02:00
He Zhe e6fe3e5b7d printk: Give error on attempt to set log buffer length to over 2G
The current printk() is ready to handle log buffer size up to 2G.
Give an explicit error for users who want to use larger log buffer.

Also fix printk formatting to show the 2G as a positive number.

Link: http://lkml.kernel.org/r/20181008135916.gg4kkmoki5bgtco5@pathway.suse.cz
Cc: rostedt@goodmis.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
[pmladek: Fixed to the really safe limit 2GB.]
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-09 14:02:05 +02:00
Lance Roy 4de1a293a0 futex: Replace spin_is_locked() with lockdep
lockdep_assert_held() is better suited for checking locking requirements,
since it won't get confused when the lock is held by some other task. This
is also a step towards possibly removing spin_is_locked().

Signed-off-by: Lance Roy <ldr709@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Link: https://lkml.kernel.org/r/20181003053902.6910-12-ldr709@gmail.com
2018-10-09 13:19:28 +02:00
Waiman Long 8ca2b56cd7 locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y
A sizable portion of the CPU cycles spent on the __lock_acquire() is used
up by the atomic increment of the class->ops stat counter. By taking it out
from the lock_class structure and changing it to a per-cpu per-lock-class
counter, we can reduce the amount of cacheline contention on the class
structure when multiple CPUs are trying to acquire locks of the same
class simultaneously.

To limit the increase in memory consumption because of the percpu nature
of that counter, it is now put back under the CONFIG_DEBUG_LOCKDEP
config option. So the memory consumption increase will only occur if
CONFIG_DEBUG_LOCKDEP is defined. The lock_class structure, however,
is reduced in size by 16 bytes on 64-bit archs after ops removal and
a minor restructuring of the fields.

This patch also fixes a bug in the increment code as the counter is of
the 'unsigned long' type, but atomic_inc() was used to increment it.

Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/d66681f3-8781-9793-1dcf-2436a284550b@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-09 09:56:33 +02:00
David S. Miller 071a234ad7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2018-10-08

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) sk_lookup_[tcp|udp] and sk_release helpers from Joe Stringer which allow
BPF programs to perform lookups for sockets in a network namespace. This would
allow programs to determine early on in processing whether the stack is
expecting to receive the packet, and perform some action (eg drop,
forward somewhere) based on this information.

2) per-cpu cgroup local storage from Roman Gushchin.
Per-cpu cgroup local storage is very similar to simple cgroup storage
except all the data is per-cpu. The main goal of per-cpu variant is to
implement super fast counters (e.g. packet counters), which don't require
neither lookups, neither atomic operations in a fast path.
The example of these hybrid counters is in selftests/bpf/netcnt_prog.c

3) allow HW offload of programs with BPF-to-BPF function calls from Quentin Monnet

4) support more than 64-byte key/value in HW offloaded BPF maps from Jakub Kicinski

5) rename of libbpf interfaces from Andrey Ignatov.
libbpf is maturing as a library and should follow good practices in
library design and implementation to play well with other libraries.
This patch set brings consistent naming convention to global symbols.

6) relicense libbpf as LGPL-2.1 OR BSD-2-Clause from Alexei Starovoitov
to let Apache2 projects use libbpf

7) various AF_XDP fixes from Björn and Magnus
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08 23:42:44 -07:00
Geert Uytterhoeven b8d62f33b7 genirq: Fix grammar s/an /a /
Fix a grammar mistake in <linux/interrupt.h>.

[ mingo: While at it also fix another similar error in another comment as well. ]

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181008111726.26286-1-geert%2Brenesas@glider.be
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-09 07:50:41 +02:00
Christoph Hellwig 79ac32a427 dma-direct: document the zone selection logic
What we are doing here isn't quite obvious, so add a comment explaining
it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-10-09 07:43:25 +02:00
Quentin Monnet e4052d06a5 bpf: allow offload of programs with BPF-to-BPF function calls
Now that there is at least one driver supporting BPF-to-BPF function
calls, lift the restriction, in the verifier, on hardware offload of
eBPF programs containing such calls. But prevent jit_subprogs(), still
in the verifier, from being run for offloaded programs.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08 10:24:13 +02:00
Quentin Monnet c941ce9c28 bpf: add verifier callback to get stack usage info for offloaded progs
In preparation for BPF-to-BPF calls in offloaded programs, add a new
function attribute to the struct bpf_prog_offload_ops so that drivers
supporting eBPF offload can hook at the end of program verification, and
potentially extract information collected by the verifier.

Implement a minimal callback (returning 0) in the drivers providing the
structs, namely netdevsim and nfp.

This will be useful in the nfp driver, in later commits, to extract the
number of subprograms as well as the stack depth for those subprograms.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08 10:24:12 +02:00
Stephen Boyd 99c65fa7c5 dma-debug: Check for drivers mapping invalid addresses in dma_map_single()
I recently debugged a DMA mapping oops where a driver was trying to map
a buffer returned from request_firmware() with dma_map_single(). Memory
returned from request_firmware() is mapped into the vmalloc region and
this isn't a valid region to map with dma_map_single() per the DMA
documentation's "What memory is DMA'able?" section.

Unfortunately, we don't really check that in the DMA debugging code, so
enabling DMA debugging doesn't help catch this problem. Let's add a new
DMA debug function to check for a vmalloc address or an invalid virtual
address and print a warning if this happens. This makes it a little
easier to debug these sorts of problems, instead of seeing odd behavior
or crashes when drivers attempt to map the vmalloc space for DMA.

Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-10-08 09:44:17 +02:00
Eric W. Biederman 601d5abfea signal: In sigqueueinfo prefer sig not si_signo
Andrei Vagin <avagin@gmail.com> reported:

> Accoding to the man page, the user should not set si_signo, it has to be set
> by kernel.
>
> $ man 2 rt_sigqueueinfo
>
>     The uinfo argument specifies the data to accompany  the  signal.   This
>        argument  is  a  pointer to a structure of type siginfo_t, described in
>        sigaction(2) (and defined  by  including  <sigaction.h>).   The  caller
>        should set the following fields in this structure:
>
>        si_code
>               This  must  be  one of the SI_* codes in the Linux kernel source
>               file include/asm-generic/siginfo.h, with  the  restriction  that
>               the  code  must  be  negative (i.e., cannot be SI_USER, which is
>               used by the kernel to indicate a signal  sent  by  kill(2))  and
>               cannot  (since  Linux  2.6.39) be SI_TKILL (which is used by the
>               kernel to indicate a signal sent using tgkill(2)).
>
>        si_pid This should be set to a process ID, typically the process ID  of
>               the sender.
>
>        si_uid This  should  be set to a user ID, typically the real user ID of
>               the sender.
>
>        si_value
>               This field contains the user data to accompany the signal.   For
>               more information, see the description of the last (union sigval)
>               argument of sigqueue(3).
>
>        Internally, the kernel sets the si_signo field to the  value  specified
>        in  sig,  so that the receiver of the signal can also obtain the signal
>        number via that field.
>
> On Tue, Sep 25, 2018 at 07:19:02PM +0200, Eric W. Biederman wrote:
>>
>> If there is some application that calls sigqueueinfo directly that has
>> a problem with this added sanity check we can revisit this when we see
>> what kind of crazy that application is doing.
>
>
> I already know two "applications" ;)
>
> https://github.com/torvalds/linux/blob/master/tools/testing/selftests/ptrace/peeksiginfo.c
> https://github.com/checkpoint-restore/criu/blob/master/test/zdtm/static/sigpending.c
>
> Disclaimer: I'm the author of both of them.

Looking at the kernel code the historical behavior has alwasy been to prefer
the signal number passed in by the kernel.

So sigh.  Implmenet __copy_siginfo_from_user and __copy_siginfo_from_user32 to
take that signal number and prefer it.  The user of ptrace will still
use copy_siginfo_from_user and copy_siginfo_from_user32 as they do not and
never have had a signal number there.

Luckily this change has never made it farther than linux-next.

Fixes: e75dc036c4 ("signal: Fail sigqueueinfo if si_signo != sig")
Reported-by: Andrei Vagin <avagin@gmail.com>
Tested-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-08 09:35:26 +02:00
David S. Miller 72438f8cef Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-06 14:43:42 -07:00
Ingo Molnar 02678a5823 Merge branch 'core/core' into x86/build, to prevent conflicts
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-06 15:51:56 +02:00
Lianbo Jiang 9cf38d5559 kexec: Allocate decrypted control pages for kdump if SME is enabled
When SME is enabled in the first kernel, it needs to allocate decrypted
pages for kdump because when the kdump kernel boots, these pages need to
be accessed decrypted in the initial boot stage, before SME is enabled.

 [ bp: clean up text. ]

Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: kexec@lists.infradead.org
Cc: tglx@linutronix.de
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: akpm@linux-foundation.org
Cc: dan.j.williams@intel.com
Cc: bhelgaas@google.com
Cc: baiyaowei@cmss.chinamobile.com
Cc: tiwai@suse.de
Cc: brijesh.singh@amd.com
Cc: dyoung@redhat.com
Cc: bhe@redhat.com
Cc: jroedel@suse.de
Link: https://lkml.kernel.org/r/20180930031033.22110-3-lijiang@redhat.com
2018-10-06 12:01:51 +02:00
Greg Kroah-Hartman c1d84a1b42 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Dave writes:
  "Networking fixes:

  1) Fix truncation of 32-bit right shift in bpf, from Jann Horn.

  2) Fix memory leak in wireless wext compat, from Stefan Seyfried.

  3) Use after free in cfg80211's reg_process_hint(), from Yu Zhao.

  4) Need to cancel pending work when unbinding in smsc75xx otherwise
     we oops, also from Yu Zhao.

  5) Don't allow enslaving a team device to itself, from Ido Schimmel.

  6) Fix backwards compat with older userspace for rtnetlink FDB dumps.
     From Mauricio Faria.

  7) Add validation of tc policy netlink attributes, from David Ahern.

  8) Fix RCU locking in rawv6_send_hdrinc(), from Wei Wang."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (26 commits)
  net: mvpp2: Extract the correct ethtype from the skb for tx csum offload
  ipv6: take rcu lock in rawv6_send_hdrinc()
  net: sched: Add policy validation for tc attributes
  rtnetlink: fix rtnl_fdb_dump() for ndmsg header
  yam: fix a missing-check bug
  net: bpfilter: Fix type cast and pointer warnings
  net: cxgb3_main: fix a missing-check bug
  bpf: 32-bit RSH verification must truncate input before the ALU op
  net: phy: phylink: fix SFP interface autodetection
  be2net: don't flip hw_features when VXLANs are added/deleted
  net/packet: fix packet drop as of virtio gso
  net: dsa: b53: Keep CPU port as tagged in all VLANs
  openvswitch: load NAT helper
  bnxt_en: get the reduced max_irqs by the ones used by RDMA
  bnxt_en: free hwrm resources, if driver probe fails.
  bnxt_en: Fix enables field in HWRM_QUEUE_COS2BW_CFG request
  bnxt_en: Fix VNIC reservations on the PF.
  team: Forbid enslaving team device to itself
  net/usb: cancel pending work when unbinding smsc75xx
  mlxsw: spectrum: Delete RIF when VLAN device is removed
  ...
2018-10-06 02:11:30 -07:00
Greg Kroah-Hartman 31d099085d Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Ingo writes:
  "perf fixes:
    - fix a CPU#0 hot unplug bug and a PCI enumeration bug in the x86 Intel uncore PMU driver
    - fix a CPU event enumeration bug in the x86 AMD PMU driver
    - fix a perf ring-buffer corruption bug when using tracepoints
    - fix a PMU unregister locking bug"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events
  perf/x86/intel/uncore: Fix PCI BDF address of M3UPI on SKX
  perf/ring_buffer: Prevent concurent ring buffer access
  perf/x86/intel/uncore: Use boot_cpu_data.phys_proc_id instead of hardcorded physical package ID 0
  perf/core: Fix perf_pmu_unregister() locking
2018-10-05 16:07:13 -07:00
Greg Kroah-Hartman 8be673735e Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Ingo writes:
  "scheduler fixes:

   These fixes address a rather involved performance regression between
   v4.17->v4.19 in the sched/numa auto-balancing code. Since distros
   really need this fix we accelerated it to sched/urgent for a faster
   upstream merge.

   NUMA scheduling and balancing performance is now largely back to
   v4.17 levels, without reintroducing the NUMA placement bugs that
   v4.18 and v4.19 fixed.

   Many thanks to Srikar Dronamraju, Mel Gorman and Jirka Hladky, for
   reporting, testing, re-testing and solving this rather complex set of
   bugs."

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/numa: Migrate pages to local nodes quicker early in the lifetime of a task
  mm, sched/numa: Remove rate-limiting of automatic NUMA balancing migration
  sched/numa: Avoid task migration for small NUMA improvement
  mm/migrate: Use spin_trylock() while resetting rate limit
  sched/numa: Limit the conditions where scan period is reset
  sched/numa: Reset scan rate whenever task moves across nodes
  sched/numa: Pass destination CPU as a parameter to migrate_task_rq
  sched/numa: Stop multiple tasks from moving to the CPU at the same time
2018-10-05 15:39:38 -07:00
David S. Miller b8d5b7cec4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-10-05

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix to truncate input on ALU operations in 32 bit mode, from Jann.

2) Fixes for cgroup local storage to reject reserved flags on element
   update and rejection of map allocation with zero-sized value, from Roman.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-05 10:53:13 -07:00
Jann Horn b799207e1e bpf: 32-bit RSH verification must truncate input before the ALU op
When I wrote commit 468f6eafa6 ("bpf: fix 32-bit ALU op verification"), I
assumed that, in order to emulate 64-bit arithmetic with 32-bit logic, it
is sufficient to just truncate the output to 32 bits; and so I just moved
the register size coercion that used to be at the start of the function to
the end of the function.

That assumption is true for almost every op, but not for 32-bit right
shifts, because those can propagate information towards the least
significant bit. Fix it by always truncating inputs for 32-bit ops to 32
bits.

Also get rid of the coerce_reg_to_size() after the ALU op, since that has
no effect.

Fixes: 468f6eafa6 ("bpf: fix 32-bit ALU op verification")
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-05 18:41:45 +02:00
He Zhe dd5adbfbfc printk: Add KBUILD_MODNAME and remove a redundant print prefix
Add KBUILD_MODNAME to make prints more clear.

Link: http://lkml.kernel.org/r/1538239553-81805-3-git-send-email-zhe.he@windriver.com
Cc: rostedt@goodmis.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-05 15:29:25 +02:00
He Zhe 51a72ab737 printk: Correct wrong casting
log_first_seq and console_seq are 64-bit unsigned integers.
Correct a wrong casting that might cut off the output.

Link: http://lkml.kernel.org/r/1538239553-81805-2-git-send-email-zhe.he@windriver.com
Cc: rostedt@goodmis.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: He Zhe <zhe.he@windriver.com>
[sergey.senozhatsky@gmail.com: More descriptive commit message]
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-05 15:02:35 +02:00
He Zhe 277fcdb2cf printk: Fix panic caused by passing log_buf_len to command line
log_buf_len_setup does not check input argument before passing it to
simple_strtoull. The argument would be a NULL pointer if "log_buf_len",
without its value, is set in command line and thus causes the following
panic.

PANIC: early exception 0xe3 IP 10:ffffffffaaeacd0d error 0 cr2 0x0
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc4-yocto-standard+ #1
[    0.000000] RIP: 0010:_parse_integer_fixup_radix+0xd/0x70
...
[    0.000000] Call Trace:
[    0.000000]  simple_strtoull+0x29/0x70
[    0.000000]  memparse+0x26/0x90
[    0.000000]  log_buf_len_setup+0x17/0x22
[    0.000000]  do_early_param+0x57/0x8e
[    0.000000]  parse_args+0x208/0x320
[    0.000000]  ? rdinit_setup+0x30/0x30
[    0.000000]  parse_early_options+0x29/0x2d
[    0.000000]  ? rdinit_setup+0x30/0x30
[    0.000000]  parse_early_param+0x36/0x4d
[    0.000000]  setup_arch+0x336/0x99e
[    0.000000]  start_kernel+0x6f/0x4ee
[    0.000000]  x86_64_start_reservations+0x24/0x26
[    0.000000]  x86_64_start_kernel+0x6f/0x72
[    0.000000]  secondary_startup_64+0xa4/0xb0

This patch adds a check to prevent the panic.

Link: http://lkml.kernel.org/r/1538239553-81805-1-git-send-email-zhe.he@windriver.com
Cc: stable@vger.kernel.org
Cc: rostedt@goodmis.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-05 14:11:12 +02:00
Borislav Petkov d0e7d14455 cpu/SMT: State SMT is disabled even with nosmt and without "=force"
When booting with "nosmt=force" a message is issued into dmesg to
confirm that SMT has been force-disabled but such a message is not
issued when only "nosmt" is on the kernel command line.

Fix that.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181004172227.10094-1-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-05 10:20:31 +02:00
Alexander Duyck 1fc8e6423e dma-direct: fix return value of dma_direct_supported
It appears that in commit 9d7a224b46 ("dma-direct: always allow dma mask
<= physiscal memory size") the logic of the test was changed from a "<" to
a ">=" however I don't see any reason for that change. I am assuming that
there was some additional change planned, specifically I suspect the logic
was intended to be reversed and possibly used for a return. Since that is
the case I have gone ahead and done that.

This addresses issues I had on my system that prevented me from booting
with the above mentioned commit applied on an x86_64 system w/ Intel IOMMU.

Fixes: 9d7a224b46 ("dma-direct: always allow dma mask <= physiscal memory size")
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-10-05 09:15:15 +02:00
Thomas Gleixner d67f34c19a clocksource: Provide clocksource_arch_init()
Architectures have extra archdata in the clocksource, e.g. for VDSO
support. There are no sanity checks or general initializations for this
available. Add support for that.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Matt Rickard <matt@softrans.com.au>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: devel@linuxdriverproject.org
Cc: virtualization@lists.linux-foundation.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20180917130706.973042587@linutronix.de
2018-10-04 23:00:24 +02:00
Tejun Heo 479adb89a9 cgroup: Fix dom_cgrp propagation when enabling threaded mode
A cgroup which is already a threaded domain may be converted into a
threaded cgroup if the prerequisite conditions are met.  When this
happens, all threaded descendant should also have their ->dom_cgrp
updated to the new threaded domain cgroup.  Unfortunately, this
propagation was missing leading to the following failure.

  # cd /sys/fs/cgroup/unified
  # cat cgroup.subtree_control    # show that no controllers are enabled

  # mkdir -p mycgrp/a/b/c
  # echo threaded > mycgrp/a/b/cgroup.type

  At this point, the hierarchy looks as follows:

      mycgrp [d]
	  a [dt]
	      b [t]
		  c [inv]

  Now let's make node "a" threaded (and thus "mycgrp" s made "domain threaded"):

  # echo threaded > mycgrp/a/cgroup.type

  By this point, we now have a hierarchy that looks as follows:

      mycgrp [dt]
	  a [t]
	      b [t]
		  c [inv]

  But, when we try to convert the node "c" from "domain invalid" to
  "threaded", we get ENOTSUP on the write():

  # echo threaded > mycgrp/a/b/c/cgroup.type
  sh: echo: write error: Operation not supported

This patch fixes the problem by

* Moving the opencoded ->dom_cgrp save and restoration in
  cgroup_enable_threaded() into cgroup_{save|restore}_control() so
  that mulitple cgroups can be handled.

* Updating all threaded descendants' ->dom_cgrp to point to the new
  dom_cgrp when enabling threaded mode.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Reported-by: Amin Jamali <ajamali@pivotal.io>
Reported-by: Joao De Almeida Pereira <jpereira@pivotal.io>
Link: https://lore.kernel.org/r/CAKgNAkhHYCMn74TCNiMJ=ccLd7DcmXSbvw3CbZ1YREeG7iJM5g@mail.gmail.com
Fixes: 454000adaa ("cgroup: introduce cgroup->dom_cgrp and threaded css_set handling")
Cc: stable@vger.kernel.org # v4.14+
2018-10-04 13:28:08 -07:00
Rafael J. Wysocki 9c2298aad3 sched/core: Fix comment regarding nr_iowait_cpu() and get_iowait_load()
The comment related to nr_iowait_cpu() and get_iowait_load() confuses
cpufreq with cpuidle and is not very useful for this reason, so fix it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linux PM <linux-pm@vger.kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: e33a9bba85 "sched/core: move IO scheduling accounting from io_schedule_timeout() into scheduler"
Link: http://lkml.kernel.org/r/3803514.xkx7zY50tF@aspire.rjw.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-04 11:25:56 +02:00
David S. Miller 6f41617bf2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor conflict in net/core/rtnetlink.c, David Ahern's bug fix in 'net'
overlapped the renaming of a netlink attribute in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-03 21:00:17 -07:00
Eric W. Biederman 4ce5f9c9e7 signal: Use a smaller struct siginfo in the kernel
We reserve 128 bytes for struct siginfo but only use about 48 bytes on
64bit and 32 bytes on 32bit.  Someday we might use more but it is unlikely
to be anytime soon.

Userspace seems content with just enough bytes of siginfo to implement
sigqueue.  Or in the case of checkpoint/restart reinjecting signals
the kernel has sent.

Reducing the stack footprint and the work to copy siginfo around from
2 cachelines to 1 cachelines seems worth doing even if I don't have
benchmarks to show a performance difference.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03 16:50:39 +02:00
Eric W. Biederman ae7795bc61 signal: Distinguish between kernel_siginfo and siginfo
Linus recently observed that if we did not worry about the padding
member in struct siginfo it is only about 48 bytes, and 48 bytes is
much nicer than 128 bytes for allocating on the stack and copying
around in the kernel.

The obvious thing of only adding the padding when userspace is
including siginfo.h won't work as there are sigframe definitions in
the kernel that embed struct siginfo.

So split siginfo in two; kernel_siginfo and siginfo.  Keeping the
traditional name for the userspace definition.  While the version that
is used internally to the kernel and ultimately will not be padded to
128 bytes is called kernel_siginfo.

The definition of struct kernel_siginfo I have put in include/signal_types.h

A set of buildtime checks has been added to verify the two structures have
the same field offsets.

To make it easy to verify the change kernel_siginfo retains the same
size as siginfo.  The reduction in size comes in a following change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03 16:47:43 +02:00
Eric W. Biederman 4cd2e0e70a signal: Introduce copy_siginfo_from_user and use it's return value
In preparation for using a smaller version of siginfo in the kernel
introduce copy_siginfo_from_user and use it when siginfo is copied from
userspace.

Make the pattern for using copy_siginfo_from_user and
copy_siginfo_from_user32 to capture the return value and return that
value on error.

This is a necessary prerequisite for using a smaller siginfo
in the kernel than the kernel exports to userspace.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03 16:47:15 +02:00
Eric W. Biederman f283801851 signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE
Rework the defintion of struct siginfo so that the array padding
struct siginfo to SI_MAX_SIZE can be placed in a union along side of
the rest of the struct siginfo members.  The result is that we no
longer need the __ARCH_SI_PREAMBLE_SIZE or SI_PAD_SIZE definitions.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03 16:46:43 +02:00
Eric W. Biederman e75dc036c4 signal: Fail sigqueueinfo if si_signo != sig
The kernel needs to validate that the contents of struct siginfo make
sense as siginfo is copied into the kernel, so that the proper union
members can be put in the appropriate locations.  The field si_signo
is a fundamental part of that validation.  As such changing the
contents of si_signo after the validation make no sense and can result
in nonsense values in the kernel.

As such simply fail if someone is silly enough to set si_signo out of
sync with the signal number passed to sigqueueinfo.

I don't expect a problem as glibc's sigqueue implementation sets
"si_signo = sig" and CRIU just returns to the kernel what the kernel
gave to it.

If there is some application that calls sigqueueinfo directly that has
a problem with this added sanity check we can revisit this when we see
what kind of crazy that application is doing.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03 16:46:28 +02:00
Eric W. Biederman 018303a931 signal/sparc: Move EMT_TAGOVF into the generic siginfo.h
When moving all of the architectures specific si_codes into
siginfo.h, I apparently overlooked EMT_TAGOVF.  Move it now.

Remove the now redundant test in siginfo_layout for SIGEMT
as now NSIGEMT is always defined.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-03 16:42:13 +02:00
Guenter Roeck e4a02ed2aa locking/ww_mutex: Fix runtime warning in the WW mutex selftest
If CONFIG_WW_MUTEX_SELFTEST=y is enabled, booting an image
in an arm64 virtual machine results in the following
traceback if 8 CPUs are enabled:

  DEBUG_LOCKS_WARN_ON(__owner_task(owner) != current)
  WARNING: CPU: 2 PID: 537 at kernel/locking/mutex.c:1033 __mutex_unlock_slowpath+0x1a8/0x2e0
  ...
  Call trace:
   __mutex_unlock_slowpath()
   ww_mutex_unlock()
   test_cycle_work()
   process_one_work()
   worker_thread()
   kthread()
   ret_from_fork()

If requesting b_mutex fails with -EDEADLK, the error variable
is reassigned to the return value from calling ww_mutex_lock
on a_mutex again. If this call fails, a_mutex is not locked.
It is, however, unconditionally unlocked subsequently, causing
the reported warning. Fix the problem by using two error variables.

With this change, the selftest still fails as follows:

  cyclic deadlock not resolved, ret[7/8] = -35

However, the traceback is gone.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Fixes: d1b42b800e ("locking/ww_mutex: Add kselftests for resolving ww_mutex cyclic deadlocks")
Link: http://lkml.kernel.org/r/1538516929-9734-1-git-send-email-linux@roeck-us.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-03 08:56:31 +02:00
Waiman Long ce52a18db4 locking/lockdep: Add a faster path in __lock_release()
When __lock_release() is called, the most likely unlock scenario is
on the innermost lock in the chain.  In this case, we can skip some of
the checks and provide a faster path to completion.

Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1538511560-10090-4-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-03 08:46:03 +02:00
Waiman Long 8ee1086247 locking/lockdep: Eliminate redundant IRQs check in __lock_acquire()
The static __lock_acquire() function has only two callers:

 1) lock_acquire()
 2) reacquire_held_locks()

In lock_acquire(), raw_local_irq_save() is called beforehand. So
IRQs must have been disabled. So the check:

	DEBUG_LOCKS_WARN_ON(!irqs_disabled())

is kind of redundant in this case. So move the above check
to reacquire_held_locks() to eliminate redundant code in the
lock_acquire() path.

Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1538511560-10090-3-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-03 08:46:02 +02:00
Waiman Long 44318d5b07 locking/lockdep: Remove add_chain_cache_classes()
The inline function add_chain_cache_classes() is defined, but has no
caller. Just remove it.

Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1538511560-10090-2-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-03 08:46:02 +02:00
Joe Stringer 6acc9b432e bpf: Add helper to retrieve socket in BPF
This patch adds new BPF helper functions, bpf_sk_lookup_tcp() and
bpf_sk_lookup_udp() which allows BPF programs to find out if there is a
socket listening on this host, and returns a socket pointer which the
BPF program can then access to determine, for instance, whether to
forward or drop traffic. bpf_sk_lookup_xxx() may take a reference on the
socket, so when a BPF program makes use of this function, it must
subsequently pass the returned pointer into the newly added sk_release()
to return the reference.

By way of example, the following pseudocode would filter inbound
connections at XDP if there is no corresponding service listening for
the traffic:

  struct bpf_sock_tuple tuple;
  struct bpf_sock_ops *sk;

  populate_tuple(ctx, &tuple); // Extract the 5tuple from the packet
  sk = bpf_sk_lookup_tcp(ctx, &tuple, sizeof tuple, netns, 0);
  if (!sk) {
    // Couldn't find a socket listening for this traffic. Drop.
    return TC_ACT_SHOT;
  }
  bpf_sk_release(sk, 0);
  return TC_ACT_OK;

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer fd978bf7fd bpf: Add reference tracking to verifier
Allow helper functions to acquire a reference and return it into a
register. Specific pointer types such as the PTR_TO_SOCKET will
implicitly represent such a reference. The verifier must ensure that
these references are released exactly once in each path through the
program.

To achieve this, this commit assigns an id to the pointer and tracks it
in the 'bpf_func_state', then when the function or program exits,
verifies that all of the acquired references have been freed. When the
pointer is passed to a function that frees the reference, it is removed
from the 'bpf_func_state` and all existing copies of the pointer in
registers are marked invalid.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer 84dbf35073 bpf: Macrofy stack state copy
An upcoming commit will need very similar copy/realloc boilerplate, so
refactor the existing stack copy/realloc functions into macros to
simplify it.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer c64b798328 bpf: Add PTR_TO_SOCKET verifier type
Teach the verifier a little bit about a new type of pointer, a
PTR_TO_SOCKET. This pointer type is accessed from BPF through the
'struct bpf_sock' structure.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer 840b9615d6 bpf: Generalize ptr_or_null regs check
This check will be reused by an upcoming commit for conditional jump
checks for sockets. Refactor it a bit to simplify the later commit.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer 9d2be44a7f bpf: Reuse canonical string formatter for ctx errs
The array "reg_type_str" provides canonical formatting of register
types, however a couple of places would previously check whether a
register represented the context and write the name "context" directly.
An upcoming commit will add another pointer type to these statements, so
to provide more accurate error messages in the verifier, update these
error messages to use "reg_type_str" instead.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer aad2eeaf46 bpf: Simplify ptr_min_max_vals adjustment
An upcoming commit will add another two pointer types that need very
similar behaviour, so generalise this function now.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer f3709f69b7 bpf: Add iterator for spilled registers
Add this iterator for spilled registers, it concentrates the details of
how to get the current frame's spilled registers into a single macro
while clarifying the intention of the code which is calling the macro.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:46 +02:00
Sergey Senozhatsky 884e370ea8 printk: CON_PRINTBUFFER console registration is a bit racy
CON_PRINTBUFFER console registration requires us to do several
preparation steps:
- Rollback console_seq to replay logbuf messages which were already
  seen on other consoles;
- Set exclusive_console flag so console_unlock() will ->write() logbuf
  messages only to the exclusive_console driver.

The way we do it, however, is a bit racy

	logbuf_lock_irqsave(flags);
	console_seq = syslog_seq;
	console_idx = syslog_idx;
	logbuf_unlock_irqrestore(flags);
						<< preemption enabled
						<< irqs enabled
	exclusive_console = newcon;
	console_unlock();

We rollback console_seq under logbuf_lock with IRQs disabled, but
we set exclusive_console with local IRQs enabled and logbuf unlocked.
If the system oops-es or panic-s before we set exclusive_console - and
given that we have IRQs and preemption enabled there is such a
possibility - we will re-play all logbuf messages to every registered
console, which may be a bit annoying and time consuming.

Move exclusive_console assignment to the same IRQs-disabled and
logbuf_lock-protected section where we rollback console_seq.

Link: http://lkml.kernel.org/r/20180928095304.9972-1-sergey.senozhatsky@gmail.com
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-02 15:20:50 +02:00