Re: [for-4.18][PATCH v2] x86/amd: Address AMD erratum #1485

[Julien Grall <julien@xxxxxxx>]

Hi Alejandro,

The original e-mail didn't yet reach my inbox. So answering here as 
there are enough context.
On 13/10/2023 15:33, Alejandro Vallejo wrote:
> On Fri, Oct 13, 2023 at 09:40:52PM +0800, Andrew Cooper wrote:
> > On 13/10/2023 9:18 pm, Alejandro Vallejo wrote:
> > > diff --git a/xen/arch/x86/cpu/amd.c b/xen/arch/x86/cpu/amd.c
> > > index 4f27187f92..085c4772d7 100644
> > > --- a/xen/arch/x86/cpu/amd.c
> > > +++ b/xen/arch/x86/cpu/amd.c
> > > @@ -1167,6 +1167,14 @@ static void cf_check init_amd(struct cpuinfo_x86 *c)
> > >         if (c->x86 == 0x10)
> > >                 __clear_bit(X86_FEATURE_MONITOR, c->x86_capability);
> > >   
> > > +	/* Fix for AMD erratum #1485 */
> > > +       if (!cpu_has_hypervisor && c->x86 == 0x19 && is_zen4_uarch()) {
> > > +               rdmsrl(MSR_AMD64_BP_CFG, value);
> > > +               #define ZEN4_BP_CFG_SHARED_BTB_FIX (1ull << 5)
You are introducing a violation to MISRA Rule 7.3 [1] which was accepted 
recently. You want to use 1ULL rather than the lower case version.
[1] 
https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_07_03.c
Cheers,

--
Julien Grall