system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-10-01 00:39:03 +00:00
Code Issues Packages Projects Releases Wiki Activity
linux/arch
History
Stephen Boyd 398f74569c ARM: 8393/1: smp: Fix suspicious RCU usage with ipi tracepoints 
John Stultz reports an RCU splat on boot with ARM ipi trace
events enabled.

===============================
[ INFO: suspicious RCU usage. ]
4.1.0-rc7-00033-gb5bed2f #153 Not tainted
-------------------------------
include/trace/events/ipi.h:68 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
no locks held by swapper/0/0.

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.0-rc7-00033-gb5bed2f #153
Hardware name: Qualcomm (Flattened Device Tree)
[<c0216b08>] (unwind_backtrace) from [<c02136e8>] (show_stack+0x10/0x14)
[<c02136e8>] (show_stack) from [<c075e678>] (dump_stack+0x70/0xbc)
[<c075e678>] (dump_stack) from [<c0215a80>] (handle_IPI+0x428/0x604)
[<c0215a80>] (handle_IPI) from [<c020942c>] (gic_handle_irq+0x54/0x5c)
[<c020942c>] (gic_handle_irq) from [<c0766604>] (__irq_svc+0x44/0x7c)
Exception stack(0xc09f3f48 to 0xc09f3f90)
3f40:                   00000001 00000001 00000000 c09f73b8 c09f4528 c0a5de9c
3f60: c076b4f0 00000000 00000000 c09ef108 c0a5cec1 00000001 00000000 c09f3f90
3f80: c026bf60 c0210ab8 20000113 ffffffff
[<c0766604>] (__irq_svc) from [<c0210ab8>] (arch_cpu_idle+0x20/0x3c)
[<c0210ab8>] (arch_cpu_idle) from [<c02647f0>] (cpu_startup_entry+0x2c0/0x5dc)
[<c02647f0>] (cpu_startup_entry) from [<c099bc1c>] (start_kernel+0x358/0x3c4)
[<c099bc1c>] (start_kernel) from [<8020807c>] (0x8020807c)

At this point in the IPI handling path we haven't called
irq_enter() yet, so RCU doesn't know that we're about to exit
idle and properly warns that we're using RCU from an idle CPU.
Use trace_ipi_entry_rcuidle() instead of trace_ipi_entry() so
that RCU is informed about our exit from idle.

Fixes: 365ec7b173 ("ARM: add IPI tracepoints")
Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-06-29 11:02:55 +01:00
..
alpha alpha: kernel: osf_sys: Set 'kts.tv_nsec' only when 'tv' has effect 2015-05-26 10:01:51 -07:00
arc ARC: inline cache flush toggle helpers 2015-05-11 11:21:41 +05:30
arm ARM: 8393/1: smp: Fix suspicious RCU usage with ipi tracepoints 2015-06-29 11:02:55 +01:00
arm64 - dts: mt8173: fix compatible string 2015-06-01 17:06:51 +02:00
avr32 Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc 2015-04-15 13:53:55 -07:00
blackfin blackfin: Fix build error 2015-06-10 10:19:24 -07:00
c6x C6X Fixes for v4.1 2015-04-16 18:48:55 -04:00
cris CRIS changes for 4.1 2015-04-26 13:31:05 -07:00
frv Devicetree updates for 4.1: 2015-04-24 08:46:18 -07:00
hexagon Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc 2015-04-15 13:53:55 -07:00
ia64 ia64: make cpu_callin_map non-volatile. 2015-06-02 10:07:03 -07:00
m32r m32r: make flush_cpumask non-volatile. 2015-05-09 11:09:29 -07:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2015-04-20 10:12:29 -07:00
metag Metag architecture changes for v4.1 2015-04-24 07:56:50 -07:00
microblaze microblaze: use asm-generic for seccomp.h 2015-04-17 09:04:10 -04:00
mips MIPS: MSA: bugfix - disable MSA correctly for new threads/processes. 2015-06-10 11:24:53 +02:00
mn10300 Devicetree updates for 4.1: 2015-04-24 08:46:18 -07:00
nios2 nios2 update for v4.1-rc1 2015-04-24 07:59:07 -07:00
openrisc Merge branch 'akpm' (patches from Andrew) 2015-04-15 16:39:15 -07:00
parisc parisc,metag: Fix crashes due to stack randomization on stack-grows-upwards architectures 2015-05-12 22:03:44 +02:00
powerpc This pull request includes a fix for two oopses, one on PPC 2015-05-21 20:15:16 -07:00
s390 s390/bpf: fix bpf frame pointer setup 2015-06-03 19:31:39 -07:00
score score: Fix exception handler label 2015-06-10 10:19:47 -07:00
sh Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma 2015-04-24 09:49:37 -07:00
sparc sparc: Resolve conflict between sparc v9 and M7 on usage of bit 9 of TTE 2015-05-31 22:15:01 -07:00
tile tile: properly use node_isset() on a nodemask_t 2015-04-28 10:36:45 -04:00
um Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc 2015-04-15 13:53:55 -07:00
unicore32 Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc 2015-04-15 13:53:55 -07:00
x86 Merge git://git.kernel.org/pub/scm/virt/kvm/kvm 2015-06-17 20:54:47 -10:00
xtensa xtensa: Provide dummy dma_alloc_attrs() and dma_free_attrs() 2015-05-25 23:03:16 +00:00
.gitignore
Kconfig powerpc updates for 4.1 2015-04-16 13:53:32 -05:00