Re: [linus:master] [x86/bugs] 6613d82e61: general_protection_fault:#[##]

[Pawan Gupta]

On Sun, Apr 14, 2024 at 08:41:52AM +0200, Linux regression tracking (Thorsten Leemhuis) wrote:
> Hi, Thorsten here, the Linux kernel's regression tracker.
> 
> On 28.03.24 22:17, Pawan Gupta wrote:
> > On Thu, Mar 28, 2024 at 03:36:28PM +0800, kernel test robot wrote:
> >> compiler: clang-17
> >> test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G
> >>
> >> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> >> the same patch/commit), kindly add following tags
> >> | Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> >> | Closes: https://lore.kernel.org/oe-lkp/202403281553.79f5a16f-lkp@xxxxxxxxx
> 
> TWIMC, a user report general protection faults with dosemu that were
> bisected to a 6.6.y backport of the commit that causes the problem
> discussed in this thread (6613d82e617dd7 ("x86/bugs: Use ALTERNATIVE()
> instead of mds_user_clear static key")).
> 
> User compiles using gcc, so it might be a different problem. Happens
> with 6.8.y as well.
> 
> The problem occurs with x86-32 kernels, but strangely only on some of
> the x86-32 systems the reporter has (e.g. on some everything works
> fine). Makes me wonder if the commit exposed an older problem that only
> happens on some machines.
> 
> For details see https://bugzilla.kernel.org/show_bug.cgi?id=218707
> Could not CC the reporter here due to the bugzilla privacy policy; if
> you want to get in contact, please use bugzilla.

Sorry for the late response, I was off work. I will look into this and
get back. I might need help reproducing this issue, but let me first see
if I can reproduce with the info in the bugzilla.