[lkml]   [2022]   [Aug]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [RESEND] x86/bus_lock: Don't assume the init value of DEBUGCTLMSR.BUS_LOCK_DETECT to be zero

On 8/2/2022 6:51 PM, Ingo Molnar wrote:
> * Chenyi Qiang <> wrote:
>> It's possible that BIOS/firmware has set DEBUGCTLMSR_BUS_LOCK_DETECT, or
>> this kernel has been kexec'd from a kernel that enabled bus lock
>> detection.
>> Disable bus lock detection explicitly if not wanted.
> Makes sense.
> Just curious: in what circumstances does the BIOS/firmware set
> DEBUGCTLMSR_BUS_LOCK_DETECT? Does it use it, or does it enable it for some
> spurious reason, without really using the feature? (Assuming you are aware
> of instances where this happened - or was this simply a hypothetical?)

Yes, It's just a hypothetical for BIOS/firmware. Kexec is the real case
I met with this problem.

> Thanks,
> Ingo

 \ /
  Last update: 2022-08-02 13:30    [W:0.144 / U:1.304 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site