linux/arch
Thomas Gleixner 6d11b87d55 powerpc/smp: Replace open coded task affinity logic
Init task invokes smp_ops->setup_cpu() from smp_cpus_done(). Init task can
run on any online CPU at this point, but the setup_cpu() callback requires
to be invoked on the boot CPU. This is achieved by temporarily setting the
affinity of the calling user space thread to the requested CPU and reset it
to the original affinity afterwards.

That's racy vs. CPU hotplug and concurrent affinity settings for that
thread resulting in code executing on the wrong CPU and overwriting the
new affinity setting.

That's actually not a problem in this context as neither CPU hotplug nor
affinity settings can happen, but the access to task_struct::cpus_allowed
is about to restricted.

Replace it with a call to work_on_cpu_safe() which achieves the same result.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Len Brown <lenb@kernel.org>
Link: http://lkml.kernel.org/r/20170412201042.518053336@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-15 12:20:54 +02:00
..
alpha alpha: fix stack smashing in old_adjtimex(2) 2017-04-03 01:06:53 -04:00
arc ARC udpates for 4.11-rc5 2017-04-01 10:52:19 -07:00
arm Merge branch 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm 2017-04-09 09:05:25 -07:00
arm64 Revert "Revert "arm64: hugetlb: partial revert of 66b3923a1a0f"" 2017-04-07 12:27:29 +01:00
avr32 arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
blackfin sched/headers: Move task->mm handling methods to <linux/sched/mm.h> 2017-03-03 01:43:28 +01:00
c6x Merge branch 'regset' (PTRACE_SETREGSET data leakage) 2017-03-29 08:55:25 -07:00
cris Merge branch 'prep-for-5level' 2017-03-10 08:59:07 -08:00
frv arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
h8300 Merge branch 'regset' (PTRACE_SETREGSET data leakage) 2017-03-29 08:55:25 -07:00
hexagon arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
ia64 ia64/sn/hwperf: Replace racy task affinity logic 2017-04-15 12:20:53 +02:00
m32r sched/headers: Move task->mm handling methods to <linux/sched/mm.h> 2017-03-03 01:43:28 +01:00
m68k m68k: Wire up statx 2017-03-20 11:27:28 +01:00
metag metag/usercopy: Fault handling fixes 2017-04-07 10:11:53 -07:00
microblaze arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
mips Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2017-04-06 13:16:34 -07:00
mn10300 arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
nios2 nios2: reserve boot memory for device tree 2017-04-02 20:13:57 -07:00
openrisc openrisc: Export symbols needed by modules 2017-03-16 00:12:57 +09:00
parisc parisc: Avoid stalled CPU warnings after system shutdown 2017-03-29 21:50:38 +02:00
powerpc powerpc/smp: Replace open coded task affinity logic 2017-04-15 12:20:54 +02:00
s390 KVM fixes for v4.11-rc6 2017-04-08 01:39:43 -07:00
score Fixup for arch/score after extable.h introduction 2017-03-11 14:16:50 -08:00
sh Merge branch 'prep-for-5level' 2017-03-10 08:59:07 -08:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2017-04-08 01:42:05 -07:00
tile arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
um arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
unicore32 arch, mm: convert all architectures to use 5level-fixup.h 2017-03-09 11:48:47 -08:00
x86 KVM fixes for v4.11-rc6 2017-04-08 01:39:43 -07:00
xtensa xtensa: wire up statx system call 2017-03-31 16:26:21 -07:00
.gitignore
Kconfig scripts/spelling.txt: add "an user" pattern and fix typo instances 2017-02-27 18:43:46 -08:00