Sebastian Andrzej Siewior f1e1c9e5e3 perf/x86/intel/bts: Make sure debug store is valid ... Since commit 4d4c474124 ("perf/x86/intel/bts: Fix BTS PMI detection") my box goes boom on boot: | .... node #0, CPUs: #1 #2 #3 #4 #5 #6 #7 | BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 | IP: [<ffffffff8100c463>] intel_bts_interrupt+0x43/0x130 | Call Trace: | <NMI> d [<ffffffff8100b341>] intel_pmu_handle_irq+0x51/0x4b0 | [<ffffffff81004d47>] perf_event_nmi_handler+0x27/0x40 This happens because the code introduced in this commit dereferences the debug store pointer unconditionally. The debug store is not guaranteed to be available, so a NULL pointer check as on other places is required. Fixes: 4d4c474124 ("perf/x86/intel/bts: Fix BTS PMI detection") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: vince@deater.net Cc: eranian@google.com Link: http://lkml.kernel.org/r/20160920131220.xg5pbdjtznszuyzb@breakpoint.cc Signed-off-by: Thomas Gleixner <tglx@linutronix.de>		2016-09-20 16:06:09 +02:00
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amd	perf/x86/amd: Make HW_CACHE_REFERENCES and HW_CACHE_MISSES measure L2	2016-09-16 16:19:49 +02:00
intel	perf/x86/intel/bts: Make sure debug store is valid	2016-09-20 16:06:09 +02:00
core.c	Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-08-06 09:10:36 -04:00
Kconfig	perf/x86: Move Kconfig.perf and other perf configuration bits to events/Kconfig	2016-03-31 10:30:40 +02:00
Makefile	x86/perf/intel/uncore: Make the Intel uncore PMU driver modular	2016-03-31 10:30:34 +02:00
msr.c	Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-07-30 12:56:26 -07:00
perf_event.h	perf/x86/intel: Fix MSR_LAST_BRANCH_FROM_x bug when no TSX	2016-06-27 11:34:19 +02:00