Alexander Shishkin <alexander.shish...@linux.intel.com> writes:
> Sebastian Andrzej Siewior <sebast...@breakpoint.cc> writes:
>> From: Sebastian Andrzej Siewior <bige...@linutronix.de>
>> Since commit 4d4c47412464 ("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
>> I don't know what is going on here but ds is not always dereferenced
>> unconditionally hence here the `ds' check to avoid the crash.
> Good catch! I'm going to guess you don't have the NMI watchdog enabled?
That is to say,
Reviewed-by: Alexander Shishkin <alexander.shish...@linux.intel.com>