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>