linux/arch/powerpc
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
..
boot powerpc/boot: Fix zImage TOC alignment 2017-03-08 10:39:32 +11:00
configs powerpc updates for 4.11 part 2 2017-03-01 10:10:16 -08:00
crypto powerpc/crypto/crc32c-vpmsum: Fix missing preempt_disable() 2017-04-07 21:12:58 +10:00
include powerpc: Wire up statx() syscall 2017-03-16 20:45:53 +11:00
kernel powerpc/smp: Replace open coded task affinity logic 2017-04-15 12:20:54 +02:00
kvm KVM: PPC: Book3S HV: Check for kmalloc errors in ioctl 2017-04-06 15:50:43 +10:00
lib powerpc fixes for 4.11 #3 2017-03-07 10:46:10 -08:00
math-emu Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mm powerpc/mm: Add missing global TLB invalidate if cxl is active 2017-04-05 22:13:37 +10:00
net powerpc updates for 4.11 part 1. 2017-02-22 10:30:38 -08:00
oprofile ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
perf powerpc/perf: Handle sdar_mode for marked event in power9 2017-03-09 13:34:54 +11:00
platforms powerpc/pseries: Don't give a warning when HPT resizing isn't available 2017-03-17 16:10:58 +11:00
purgatory kexec, x86/purgatory: Unbreak it and clean it up 2017-03-10 20:55:09 +01:00
scripts powerpc/ftrace: Add Kconfig & Make glue for mprofile-kernel 2016-03-07 14:53:56 +11:00
sysdev axonram: Fix gendisk handling 2017-03-08 10:55:40 -07:00
xmon sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> 2017-03-02 08:42:29 +01:00
Kconfig powerpc: Sort the selects under CONFIG_PPC 2017-03-06 23:05:42 +11:00
Kconfig.debug powerpc/xmon: Enable disassembly files (compilation changes) 2017-02-15 20:02:42 +11:00
Makefile powerpc: Fix compiling a BE kernel with a powerpc64le toolchain 2017-03-03 11:24:50 +11:00
relocs_check.sh powerpc/64: whitelist unresolved modversions CRCs 2016-09-22 14:46:31 +02:00