Commits
Kan Liang committed b257bb437dc
perf/x86/intel/uncore: Reduce the number of CBOX counters
[ Upstream commit ee139385432e919f4d1f59b80edbc073cdae1391 ]
An oops is triggered by the fuzzy test.
[ 327.853081] unchecked MSR access error: RDMSR from 0x70c at rIP:
0xffffffffc082c820 (uncore_msr_read_counter+0x10/0x50 [intel_uncore])
[ 327.853083] Call Trace:
[ 327.853085] <IRQ>
[ 327.853089] uncore_pmu_event_start+0x85/0x170 [intel_uncore]
[ 327.853093] uncore_pmu_event_add+0x1a4/0x410 [intel_uncore]
[ 327.853097] ? event_sched_in.isra.118+0xca/0x240
There are 2 GP counters for each CBOX, but the current code claims 4
counters. Accessing the invalid registers triggers the oops.
Fixes: 6e394376ee89 ("perf/x86/intel/uncore: Add Intel Icelake uncore support")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200925134905.8839-3-kan.liang@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>