arm64 KASAN_HW_TAGS panic on non-MTE hardware on 5.12-rc1

[Andrey Konovalov]

On Sat, Mar 6, 2021 at 1:01 PM Catalin Marinas <catalin.marinas at arm.com> wrote:
>
> On Fri, Mar 05, 2021 at 07:36:22PM +0100, Andrey Konovalov wrote:
> > On Fri, Mar 5, 2021 at 6:52 PM Catalin Marinas <catalin.marinas at arm.com> wrote:
> > > > > This is weird. kasan_unpoison_task_stack() is only defined when
> > > > > CONFIG_KASAN_STACK is enabled, which shouldn't be enablable for
> > > > > HW_TAGS.
> > > >
> > > > CONFIG_KASAN=y
> > > > # CONFIG_KASAN_GENERIC is not set
> > > > CONFIG_KASAN_HW_TAGS=y
> > > > CONFIG_KASAN_STACK=1
> > >
> > > From Kconfig:
> > >
> > > config KASAN_STACK
> > >         int
> > >         default 1 if KASAN_STACK_ENABLE || CC_IS_GCC
> > >         default 0
> > >
> > > and I use gcc.
> >
> > Ah, that explains it.
> >
> > Could you try applying this patch and see if it fixes the issue?
> >
> > https://patchwork.kernel.org/project/linux-mm/patch/20210226012531.29231-1-walter-zh.wu@mediatek.com/
>
> Walter's patches already in -next fix this issue.

Great!

I'll still send a patch as we need the fix in older kernels too.

Thanks for the report!