If the firmware returns an error such as "closed" (or hardware
error), we should drop characters.
Currently we only do that when a firmware compatible with OPAL v2
APIs is detected, in the code that calls opal_console_write_buffer_space(),
which didn't exist with OPAL v1 (or didn't work).
However, when enabling early debug consoles, the flag indicating
that v2 is supported isn't set yet, causing us, in case of errors
or closed console, to spin forever.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds a new udbg early debug console which utilises
statically defined input and output buffers stored within the kernel
BSS. It is primarily designed to assist with bring up of new hardware
which may not have a working console but which has a method of
reading/writing kernel memory.
This version incorporates comments made by Ben H (thanks!).
Changes from v1:
- Add memory barriers.
- Ensure updating of read/write positions is atomic.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If hard_irq_disable() is called while interrupts are already soft-disabled
(which is the most common case) all is already well.
However you can (and in some cases want) to call it while everything is
enabled (to make sure you don't get a lazy even, for example before entry
into KVM guests) and in this case we need to inform the irq tracer that
the irqs are going off.
We have to change the inline into a macro to avoid an include circular
dependency hell hole.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We are registering the attribute with permission 0600 but it
doesn't have a store callback, which causes WARN_ON's during
boot. Fix the permission.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The PCI core supports an offset per aperture nowadays but our arch
code still has a single offset per host bridge representing the
difference betwen CPU memory addresses and PCI MMIO addresses.
This is a problem as new machines and hypervisor versions are
coming out where the 64-bit windows will have a different offset
(basically mapped 1:1) from the 32-bit windows.
This fixes it by using separate offsets. In the long run, we probably
want to get rid of that intermediary struct pci_controller and have
those directly stored into the pci_host_bridge as they are parsed
but this will be a more invasive change.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some devices don't have a correct node ID and thus can't be
attached to an iommu.
The message displayed by the iommu code isn't very useful if
you don't have a device-tree node as it tries to print the
device-tree path but not the struct device name.
Improve this by printing the device name as well.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We are registering the attribute with permission 0644 but it
doesn't have a store callback, which causes WARN_ON's during
boot. Fix the permission.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some interrupt controllers refuse to map interrupts marked as
"protected" by firwmare. Since we try to map everyting in the
device-tree on some platforms, we end up with a lot of nasty
WARN's in the boot log for what is a normal situation on those
machines.
This defines a specific return code (-EPERM) from the host map()
callback which cause irqdomain to fail silently.
MPIC is updated to return this when hitting a protected source
printing only a single line message for diagnostic purposes.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The property should be "ibm,power8-pciex", not "ibm,p8-pciex". The latter
was changed in FW because it was inconsistent with the rest of the nodes.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When converting to use the new pci_add_resource_offset() we didn't
properly account for empty resources (0 flags) and add those bogons
to the PHBs. The result is some annoying messages in the log.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If OPAL returns an error, propagate it upward rather than spinning
seconds waiting for a CPU that will never show up
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Also, make HTM's presence dependent on the .config option.
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
On pseries machines the detection for max_bus_speed should be done
through an OpenFirmware property. This patch adds a function to perform
this detection and a hook to perform dynamic adding of the function only
for pseries. This is done by overwriting the weak
pcibios_root_bridge_prepare function which is called by
pci_create_root_bus().
From: Lucas Kannebley Tavares <lucaskt@linux.vnet.ibm.com>
Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The following patch implements a new PAPR change which allows
the OS to force the use of 32 bit MSIs, regardless of what
the PCI capabilities indicate. This is required for some
devices that advertise support for 64 bit MSIs but don't
actually support them.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Make sure that current->thread.reg exists before we deference it in
flush_hash_page.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reported-by: John J Miller <millerjo@us.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently, the OPAL exception vectors are registered before the feature
fixups are processed. This means that the now-firmware-owned vectors
will likely be overwritten by the kernel.
This change moves the exception registration code to an early initcall,
rather than at machine_init time.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
POWER8 allows read and write of the DSCR in userspace. We added
kernel emulation so applications could always use the instructions
regardless of the CPU type.
Unfortunately there are two SPRs for the DSCR and we only added
emulation for the privileged one. Add code to match the non
privileged one.
A simple test was created to verify the fix:
http://ozlabs.org/~anton/junkcode/user_dscr_test.c
Without the patch we get a SIGILL and it passes with the patch.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Pull kvm updates from Gleb Natapov:
"Highlights of the updates are:
general:
- new emulated device API
- legacy device assignment is now optional
- irqfd interface is more generic and can be shared between arches
x86:
- VMCS shadow support and other nested VMX improvements
- APIC virtualization and Posted Interrupt hardware support
- Optimize mmio spte zapping
ppc:
- BookE: in-kernel MPIC emulation with irqfd support
- Book3S: in-kernel XICS emulation (incomplete)
- Book3S: HV: migration fixes
- BookE: more debug support preparation
- BookE: e6500 support
ARM:
- reworking of Hyp idmaps
s390:
- ioeventfd for virtio-ccw
And many other bug fixes, cleanups and improvements"
* tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
kvm: Add compat_ioctl for device control API
KVM: x86: Account for failing enable_irq_window for NMI window request
KVM: PPC: Book3S: Add API for in-kernel XICS emulation
kvm/ppc/mpic: fix missing unlock in set_base_addr()
kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write
kvm/ppc/mpic: remove users
kvm/ppc/mpic: fix mmio region lists when multiple guests used
kvm/ppc/mpic: remove default routes from documentation
kvm: KVM_CAP_IOMMU only available with device assignment
ARM: KVM: iterate over all CPUs for CPU compatibility check
KVM: ARM: Fix spelling in error message
ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally
KVM: ARM: Fix API documentation for ONE_REG encoding
ARM: KVM: promote vfp_host pointer to generic host cpu context
ARM: KVM: add architecture specific hook for capabilities
ARM: KVM: perform HYP initilization for hotplugged CPUs
ARM: KVM: switch to a dual-step HYP init code
ARM: KVM: rework HYP page table freeing
ARM: KVM: enforce maximum size for identity mapped code
ARM: KVM: move to a KVM provided HYP idmap
...
Give the OID registry file module information so that it doesn't taint the
kernel when compiled as a module and loaded.
Reported-by: Dros Adamson <Weston.Adamson@netapp.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Trond Myklebust <Trond.Myklebust@netapp.com>
cc: stable@vger.kernel.org
cc: linux-nfs@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull 'full dynticks' support from Ingo Molnar:
"This tree from Frederic Weisbecker adds a new, (exciting! :-) core
kernel feature to the timer and scheduler subsystems: 'full dynticks',
or CONFIG_NO_HZ_FULL=y.
This feature extends the nohz variable-size timer tick feature from
idle to busy CPUs (running at most one task) as well, potentially
reducing the number of timer interrupts significantly.
This feature got motivated by real-time folks and the -rt tree, but
the general utility and motivation of full-dynticks runs wider than
that:
- HPC workloads get faster: CPUs running a single task should be able
to utilize a maximum amount of CPU power. A periodic timer tick at
HZ=1000 can cause a constant overhead of up to 1.0%. This feature
removes that overhead - and speeds up the system by 0.5%-1.0% on
typical distro configs even on modern systems.
- Real-time workload latency reduction: CPUs running critical tasks
should experience as little jitter as possible. The last remaining
source of kernel-related jitter was the periodic timer tick.
- A single task executing on a CPU is a pretty common situation,
especially with an increasing number of cores/CPUs, so this feature
helps desktop and mobile workloads as well.
The cost of the feature is mainly related to increased timer
reprogramming overhead when a CPU switches its tick period, and thus
slightly longer to-idle and from-idle latency.
Configuration-wise a third mode of operation is added to the existing
two NOHZ kconfig modes:
- CONFIG_HZ_PERIODIC: [formerly !CONFIG_NO_HZ], now explicitly named
as a config option. This is the traditional Linux periodic tick
design: there's a HZ tick going on all the time, regardless of
whether a CPU is idle or not.
- CONFIG_NO_HZ_IDLE: [formerly CONFIG_NO_HZ=y], this turns off the
periodic tick when a CPU enters idle mode.
- CONFIG_NO_HZ_FULL: this new mode, in addition to turning off the
tick when a CPU is idle, also slows the tick down to 1 Hz (one
timer interrupt per second) when only a single task is running on a
CPU.
The .config behavior is compatible: existing !CONFIG_NO_HZ and
CONFIG_NO_HZ=y settings get translated to the new values, without the
user having to configure anything. CONFIG_NO_HZ_FULL is turned off by
default.
This feature is based on a lot of infrastructure work that has been
steadily going upstream in the last 2-3 cycles: related RCU support
and non-periodic cputime support in particular is upstream already.
This tree adds the final pieces and activates the feature. The pull
request is marked RFC because:
- it's marked 64-bit only at the moment - the 32-bit support patch is
small but did not get ready in time.
- it has a number of fresh commits that came in after the merge
window. The overwhelming majority of commits are from before the
merge window, but still some aspects of the tree are fresh and so I
marked it RFC.
- it's a pretty wide-reaching feature with lots of effects - and
while the components have been in testing for some time, the full
combination is still not very widely used. That it's default-off
should reduce its regression abilities and obviously there are no
known regressions with CONFIG_NO_HZ_FULL=y enabled either.
- the feature is not completely idempotent: there is no 100%
equivalent replacement for a periodic scheduler/timer tick. In
particular there's ongoing work to map out and reduce its effects
on scheduler load-balancing and statistics. This should not impact
correctness though, there are no known regressions related to this
feature at this point.
- it's a pretty ambitious feature that with time will likely be
enabled by most Linux distros, and we'd like you to make input on
its design/implementation, if you dislike some aspect we missed.
Without flaming us to crisp! :-)
Future plans:
- there's ongoing work to reduce 1Hz to 0Hz, to essentially shut off
the periodic tick altogether when there's a single busy task on a
CPU. We'd first like 1 Hz to be exposed more widely before we go
for the 0 Hz target though.
- once we reach 0 Hz we can remove the periodic tick assumption from
nr_running>=2 as well, by essentially interrupting busy tasks only
as frequently as the sched_latency constraints require us to do -
once every 4-40 msecs, depending on nr_running.
I am personally leaning towards biting the bullet and doing this in
v3.10, like the -rt tree this effort has been going on for too long -
but the final word is up to you as usual.
More technical details can be found in Documentation/timers/NO_HZ.txt"
* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
sched: Keep at least 1 tick per second for active dynticks tasks
rcu: Fix full dynticks' dependency on wide RCU nocb mode
nohz: Protect smp_processor_id() in tick_nohz_task_switch()
nohz_full: Add documentation.
cputime_nsecs: use math64.h for nsec resolution conversion helpers
nohz: Select VIRT_CPU_ACCOUNTING_GEN from full dynticks config
nohz: Reduce overhead under high-freq idling patterns
nohz: Remove full dynticks' superfluous dependency on RCU tree
nohz: Fix unavailable tick_stop tracepoint in dynticks idle
nohz: Add basic tracing
nohz: Select wide RCU nocb for full dynticks
nohz: Disable the tick when irq resume in full dynticks CPU
nohz: Re-evaluate the tick for the new task after a context switch
nohz: Prepare to stop the tick on irq exit
nohz: Implement full dynticks kick
nohz: Re-evaluate the tick from the scheduler IPI
sched: New helper to prevent from stopping the tick in full dynticks
sched: Kick full dynticks CPU that have more than one task enqueued.
perf: New helper to prevent full dynticks CPUs from stopping tick
perf: Kick full dynticks CPU if events rotation is needed
...
Pull perf fixes from Ingo Molnar:
"Misc fixes plus a small hw-enablement patch for Intel IB model 58
uncore events"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL
perf/x86/intel/lbr: Fix LBR filter
perf/x86: Blacklist all MEM_*_RETIRED events for Ivy Bridge
perf: Fix vmalloc ring buffer pages handling
perf/x86/intel: Fix unintended variable name reuse
perf/x86/intel: Add support for IvyBridge model 58 Uncore
perf/x86/intel: Fix typo in perf_event_intel_uncore.c
x86: Eliminate irq_mis_count counted in arch_irq_stat
fix a remove/insert race which Never Happens, and (my favorite) handle the
case when we have too many modules for a single commandline. Seriously,
the kernel is full, please go away!
Cheers,
Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull mudule updates from Rusty Russell:
"We get rid of the general module prefix confusion with a binary config
option, fix a remove/insert race which Never Happens, and (my
favorite) handle the case when we have too many modules for a single
commandline. Seriously, the kernel is full, please go away!"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
modpost: fix unwanted VMLINUX_SYMBOL_STR expansion
X.509: Support parse long form of length octets in Authority Key Identifier
module: don't unlink the module until we've removed all exposure.
kernel: kallsyms: memory override issue, need check destination buffer length
MODSIGN: do not send garbage to stderr when enabling modules signature
modpost: handle huge numbers of modules.
modpost: add -T option to read module names from file/stdin.
modpost: minor cleanup.
genksyms: pass symbol-prefix instead of arch
module: fix symbol versioning with symbol prefixes
CONFIG_SYMBOL_PREFIX: cleanup.
Pull single_open() leak fixes from Al Viro:
"A bunch of fixes for a moderately common class of bugs: file with
single_open() done by its ->open() and seq_release as its ->release().
That leaks; fortunately, it's not _too_ common (either people manage
to RTFM that says "When using single_open(), the programmer should use
single_release() instead of seq_release() in the file_operations
structure to avoid a memory leak", or they just copy a correct
instance), but grepping through the tree has caught quite a pile.
All of that is, AFAICS, -stable fodder, for as far as the patches
apply. I tried to carve it up into reasonably-sized pieces (more or
less "comes from the same tree")"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
rcutrace: single_open() leaks
gadget: single_open() leaks
staging: single_open() leaks
megaraid: single_open() leak
wireless: single_open() leaks
input: single_open() leak
rtc: single_open() leaks
ds1620: single_open() leak
sh: single_open() leaks
parisc: single_open() leaks
mips: single_open() leaks
ia64: single_open() leaks
h8300: single_open() leaks
cris: single_open() leaks
arm: single_open() leaks
Merge ipc fixes and cleanups from my IPC branch.
The ipc locking has always been pretty ugly, and the scalability fixes
to some degree made it even less readable. We had two cases of double
unlocks in error paths due to this (one rcu read unlock, one semaphore
unlock), and this fixes the bugs I found while trying to clean things up
a bit so that we are less likely to have more.
* ipc-cleanups:
ipc: simplify rcu_read_lock() in semctl_nolock()
ipc: simplify semtimedop/semctl_main() common error path handling
ipc: move sem_obtain_lock() rcu locking into the only caller
ipc: fix double sem unlock in semctl error path
ipc: move the rcu_read_lock() from sem_lock_and_putref() into callers
ipc: sem_putref() does not need the semaphore lock any more
ipc: move rcu_read_unlock() out of sem_unlock() and into callers
This API shouldn't have 32/64-bit issues, but VFS assumes it does
unless told otherwise.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Pull networking fixes from David Miller:
1) Several routines do not use netdev_features_t to hold such bitmasks,
fixes from Patrick McHardy and Bjørn Mork.
2) Update cpsw IRQ software state and the actual HW irq enabling in the
correct order. From Mugunthan V N.
3) When sending tipc packets to multiple bearers, we have to make
copies of the SKB rather than just giving the original SKB directly.
Fix from Gerlando Falauto.
4) Fix race with bridging topology change timer, from Stephen
Hemminger.
5) Fix TCPv6 segmentation handling in GRE and VXLAN, from Pravin B
Shelar.
6) Endian bug in USB pegasus driver, from Dan Carpenter.
7) Fix crashes on MTU reduction in USB asix driver, from Holger
Eitzenberger.
8) Don't allow the kernel to BUG() just because the user puts some crap
in an AF_PACKET mmap() ring descriptor. Fix from Daniel Borkmann.
9) Don't use variable sized arrays on the stack in xen-netback, from
Wei Liu.
10) Fix stats reporting and an unbalanced napi_disable() in be2net
driver. From Somnath Kotur and Ajit Khaparde.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (25 commits)
cxgb4: fix error recovery when t4_fw_hello returns a positive value
sky2: Fix crash on receiving VLAN frames
packet: tpacket_v3: do not trigger bug() on wrong header status
asix: fix BUG in receive path when lowering MTU
net: qmi_wwan: Add Telewell TW-LTE 4G
usbnet: pegasus: endian bug in write_mii_word()
vxlan: Fix TCPv6 segmentation.
gre: Fix GREv4 TCPv6 segmentation.
bridge: fix race with topology change timer
tipc: pskb_copy() buffers when sending on more than one bearer
tipc: tipc_bcbearer_send(): simplify bearer selection
tipc: cosmetic: clean up comments and break a long line
drivers: net: cpsw: irq not disabled in cpsw isr in particular sequence
xen-netback: better names for thresholds
xen-netback: avoid allocating variable size array on stack
xen-netback: remove redundent parameter in netbk_count_requests
be2net: Fix to fail probe if MSI-X enable fails for a VF
be2net: avoid napi_disable() when it has not been enabled
be2net: Fix firmware download for Lancer
be2net: Fix to receive Multicast Packets when Promiscuous mode is enabled on certain devices
...
Pull sparc updates from David Miller:
1) Hibernation support, as well as removal of excess interrupt
twiddling in MMU context allocation on sparc64 from Kirill Tkhai.
2) Kill references to __ARCH_WANT_UNLOCKED_CTXSW.
3) Sparc32 LEON bug fixes from Daniel Hellstrom and Andreas Larsson.
4) Provide cmpxchg64(), from Geert Uytterhoeven.
5) Device refcount and registry bug fixes from Federico Vaga and Wei
Yongjun.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next:
serial: sunsu: add missing platform_driver_unregister() when module exit
sparc32, leon: Do not overwrite previously set irq flow handlers
sparc/kernel/vio.c: add put_device() after device_find_child()
sparc64: Do not save/restore interrupts in get_new_mmu_context()
sparc: Consistently use 'wr' and 'rd' instructions for ASRs.
sparc64: Kill __ARCH_WANT_UNLOCKED_CTXSW
sparc64: Provide cmpxchg64()
sparc64: Do not change num_physpages during initmem freeing
sparc64: Hibernation support
sparc,leon: updated GRPCI2 config name
sparc,leon: support for GRPCI1 PCI host bridge controller
sparc32,leon: add support for PCI busn resource for GRPCI2
We have registered platform driver when module init, and
need unregister it when module exit.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is needed because when scan_of_devices finds the GAISLER_GPTIMER
core that corresponds to the SMP "ticker" timer, the previously set
proper irq flow handler gets overwritten with an incorrect one. This
leads to very flaky timer interrupt handling on some hardware. Proper
updates to handlers can still be done using leon_update_virq_handling.
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The vio_remove() function uses device_find_child() but it does not drop
the reference of the retrieved child.
Signed-off-by: Federico Vaga <federico.vaga@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>