Re: [linux-next:master] [x86/module] 6661cae1aa: WARNING:at_arch/x86/mm/pat/set_memory.c:#__cpa_process_fault

[Christophe Leroy]

Le 13/10/2024 à 10:17, Mike Rapoport a écrit :
> On Fri, Oct 11, 2024 at 09:30:33AM -0700, Dave Hansen wrote:
> > On 10/11/24 08:40, Mike Rapoport wrote:
> > > On Fri, Oct 11, 2024 at 07:00:01AM -0700, Dave Hansen wrote:
> > > > On 10/11/24 06:08, Mike Rapoport wrote:
> > > > > This patch disables ROX caches on 32-bit, it should fix the issue.
> > > > While I'm not going to shed a tear for 32-bit, what's the actual
> > > > compatibility issue with 32-bit?
> > >  From the stack trace it looks like execmem tries to update the direct map
> > > for highmem memory, and cpa is not happy about it.
> >
> > First of all, if it's a highmem problem, shouldn't the check be for
> > CONFIG_HIGHMEM and not on 32-bit vs. 64-bit?  We do have non-highmem
> > 32-bit configs.
>
> 32 bit also does not have ARCH_HUGE_VMALLOC and execmem cache will be
> anyway populated with 4k pages, so I don't see why it would be useful on 32
> bit all.
>   

Are you talking about X86 only or any architecture ?

On powerpc we have:

arch/powerpc/Kconfig:   select HAVE_ARCH_HUGE_VMALLOC           if 
HAVE_ARCH_HUGE_VMAP
arch/powerpc/Kconfig:   select HAVE_ARCH_HUGE_VMAP              if 
PPC_RADIX_MMU || PPC_8xx

PPC_8xx is 32 bits.

Christophe