[PATCH 2/2] arm64: Check if GMID_EL1.BS is the same on all CPUs

[Will Deacon]

On Wed, May 26, 2021 at 08:47:16PM +0100, Jon Hunter wrote:
> On 11/05/2021 19:23, Catalin Marinas wrote:
> > diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
> > index 4bea701117d4..cd9f2d51285b 100644
> > --- a/arch/arm64/kernel/cpuinfo.c
> > +++ b/arch/arm64/kernel/cpuinfo.c
> > @@ -359,6 +359,7 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info)
> >  	info->reg_dczid = read_cpuid(DCZID_EL0);
> >  	info->reg_midr = read_cpuid_id();
> >  	info->reg_revidr = read_cpuid(REVIDR_EL1);
> > +	info->reg_gmid = read_cpuid(GMID_EL1);
> >  
> >  	info->reg_id_aa64dfr0 = read_cpuid(ID_AA64DFR0_EL1);
> >  	info->reg_id_aa64dfr1 = read_cpuid(ID_AA64DFR1_EL1);
> 
> 
> I am seeing the following undefined instruction crash on all our 
> ARM64 Tegra devices on today's -next and bisect is pointing to
> this patch. Reverting this patch on top of -next does fix the 
> problem. Let me know if you have any thoughts.

Catalin just posted a fixed version, so should be solved asap (I'll push a
new branch shortly).

Thanks!

Will