[REGRESSION] x86/efi: Make efi_enter/leave_mm() use the use_/unuse_temporary_mm() machinery (linux-next)

[Peter Zijlstra]

On Wed, Apr 30, 2025 at 08:47:43AM +0000, Borah, Chaitanya Kumar wrote:
> 
> 
> > -----Original Message-----
> > From: Peter Zijlstra <peterz at infradead.org>
> > Sent: Tuesday, April 29, 2025 11:59 PM
> > To: Jani Nikula <jani.nikula at linux.intel.com>
> > Cc: Borah, Chaitanya Kumar <chaitanya.kumar.borah at intel.com>;
> > luto at kernel.org; intel-gfx at lists.freedesktop.org; intel-
> > xe at lists.freedesktop.org; Kurmi, Suresh Kumar
> > <suresh.kumar.kurmi at intel.com>; Saarinen, Jani <jani.saarinen at intel.com>;
> > De Marchi, Lucas <lucas.demarchi at intel.com>; linux-kernel at vger.kernel.org;
> > Ingo Molnar <mingo at kernel.org>
> > Subject: Re: [REGRESSION] x86/efi: Make efi_enter/leave_mm() use the
> > use_/unuse_temporary_mm() machinery (linux-next)
> > 
> > On Tue, Apr 29, 2025 at 12:01:22PM +0300, Jani Nikula wrote:
> > > On Thu, 24 Apr 2025, "Borah, Chaitanya Kumar"
> > <chaitanya.kumar.borah at intel.com> wrote:
> > > > +Andy, Ingo
> > > >
> > > > Friendly reminder.
> > > > Issue is still seen on latest linux-next runs.
> > > >
> > > > https://intel-gfx-ci.01.org/tree/linux-next/next-20250424/bat-rpls-4
> > > > /boot0.txt
> > > >
> > > > Regards
> > > >
> > > > Chaitanya
> > >
> > > Andy, Ingo -
> > >
> > > Commit e7021e2fe0b4 ("x86/efi: Make efi_enter/leave_mm() use the
> > > use_/unuse_temporary_mm() machinery") on linux-next regresses as
> > > reported by Chaitanya
> > >
> > > Please look into it.
> > 
> > Does your kernel include the below?
> 
> This change has not yet landed in linux-next. However, making local change on top of next-20250429 seems to help us.
> 
> Important to note that we don't CONFIG_DEBUG_VM=y as mentioned by Hugh.
> 
> Any idea when this lands in linux-next?

This is the top commit in tip/x86/alternatives and should already be in
-next, Ingo, any idea what is going wrong?