Messages in this thread | | | From | Alexander Shishkin <> | Subject | [PATCH v2 0/5] perf, bts: Fallout from the fuzzer for perf/urgent | Date | Tue, 6 Sep 2016 16:23:48 +0300 |
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Hi,
There were more bugs since the previous version, plus the BTS barriers got fixed. With these patches, my testcase keeps running and no spurious NMI warnings pop up any more.
Original story:
Recently Vince has reported warnings and panics coming from the general direction of AUX tracing. I found two bugs which manifest similarly, one in intel_bts driver and one in AUX unmapping path.
Both are triggered by racing SET_OUTPUT against mmap_close while running AUX tracing. I have a test case that set fire to the kernel within a few seconds by doing this, which I can share if anyone cares.
These are all good candidates for 4.7-stable and the BTS ones can be theoretically backported further.
Alexander Shishkin (5): perf: Fix a race between mmap_close and set_output of AUX events perf: Fix aux_mmap_count vs aux_refcount order perf/x86/intel/bts: Fix confused ordering of PMU callbacks perf/x86/intel/bts: Fix BTS PMI detection perf/x86/intel/bts: Kill a silly warning
arch/x86/events/intel/bts.c | 123 +++++++++++++++++++++++++++++++++----------- kernel/events/core.c | 31 ++++++++--- kernel/events/ring_buffer.c | 16 +++--- 3 files changed, 129 insertions(+), 41 deletions(-)
-- 2.9.3
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