linux/kernel/events
Thomas Gleixner 27ca9236c9 perf/core: Remove the bogus and dangerous CPU_DOWN_FAILED hotplug state
If CPU_DOWN_PREPARE fails the perf hotplug notifier is called for
CPU_DOWN_FAILED and calls perf_event_init_cpu(), which checks whether the
swhash is referenced. If yes it allocates a new hash and stores the pointer in
the per cpu data structure.

But at this point the cpu is still online, so there must be a valid hash
already. By overwriting the pointer the existing hash is not longer
accessible.

Remove the CPU_DOWN_FAILED state, as there is nothing to (re)allocate.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20160209201007.763417379@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 10:37:29 +01:00
..
callchain.c treewide: Remove old email address 2015-11-23 09:44:58 +01:00
core.c perf/core: Remove the bogus and dangerous CPU_DOWN_FAILED hotplug state 2016-02-17 10:37:29 +01:00
hw_breakpoint.c perf: Collapse and fix event_function_call() users 2016-01-21 18:54:24 +01:00
internal.h perf: Fix AUX buffer refcounting 2015-07-06 14:08:30 +02:00
Makefile ftrace: allow architectures to specify ftrace compile options 2015-01-29 09:19:19 +01:00
ring_buffer.c perf: Synchronously free aux pages in case of allocation failure 2016-01-21 18:54:27 +01:00
uprobes.c memcg: adjust to support new THP refcounting 2016-01-15 17:56:32 -08:00