Messages in this thread | | | Date | Tue, 9 May 2023 13:47:47 +0200 | Subject | Re: [PATCH v6 11/16] x86/mtrr: construct a memory map with cache modes | From | Juergen Gross <> |
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On 09.05.23 13:36, Borislav Petkov wrote: > On Tue, May 02, 2023 at 02:09:26PM +0200, Juergen Gross wrote: >> @@ -841,6 +1137,10 @@ static void generic_set_mtrr(unsigned int reg, unsigned long base, >> >> cache_enable(); >> local_irq_restore(flags); >> + >> + /* On the first CPU rebuild the cache mode memory map. */ >> + if (smp_processor_id() == cpumask_first(cpu_online_mask)) >> + rebuild_map(); > > I still don't like this. Anything against doing this instead?
No, Should be fine. Apart from ...
> > --- > diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c > index 163dca53796c..e69c8c56897f 100644 > --- a/arch/x86/kernel/cpu/mtrr/generic.c > +++ b/arch/x86/kernel/cpu/mtrr/generic.c > @@ -458,8 +458,11 @@ static void map_add_var(void) > * removals of registers, which are complicated to handle without rebuild of > * the map. > */ > -static void rebuild_map(void) > +void rebuild_map(void) > { > + if (mtrr_if != &generic_mtrr_ops) > + return; > + > cache_map_n = cache_map_fixed; > > map_add_var(); > @@ -1127,10 +1130,6 @@ static void generic_set_mtrr(unsigned int reg, unsigned long base, > > cache_enable(); > local_irq_restore(flags); > - > - /* On the first CPU rebuild the cache mode memory map. */ > - if (smp_processor_id() == cpumask_first(cpu_online_mask)) > - rebuild_map(); > } > > int generic_validate_add_page(unsigned long base, unsigned long size, > diff --git a/arch/x86/kernel/cpu/mtrr/legacy.c b/arch/x86/kernel/cpu/mtrr/legacy.c > index d25882fcf181..30a3d51d06e0 100644 > --- a/arch/x86/kernel/cpu/mtrr/legacy.c > +++ b/arch/x86/kernel/cpu/mtrr/legacy.c > @@ -67,6 +67,7 @@ static void mtrr_restore(void) > mtrr_value[i].ltype); > } > } > + rebuild_map();
... this call not being needed at all. We can reach this point only for mtrr_if != &generic_mtrr_ops.
Juergen [unhandled content-type:application/pgp-keys][unhandled content-type:application/pgp-signature] | |