Re: [PATCH v5 03/15] arm64: errata: Add workaround for TSB flush failures

[Suzuki K Poulose]

On 19/10/2021 12:02, Will Deacon wrote:
> On Thu, Oct 14, 2021 at 11:31:13PM +0100, Suzuki K Poulose wrote:
> > diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
> > index ccd757373f36..bdbeac75ead6 100644
> > --- a/arch/arm64/kernel/cpu_errata.c
> > +++ b/arch/arm64/kernel/cpu_errata.c
> > @@ -352,6 +352,18 @@ static const struct midr_range trbe_overwrite_fill_mode_cpus[] = {
> >   };
> >   #endif	/* CONFIG_ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE */
> >   
> > +#ifdef CONFIG_ARM64_WORKAROUND_TSB_FLUSH_FAILURE
> > +static const struct midr_range tsb_flush_fail_cpus[] = {
> > +#ifdef CONFIG_ARM64_ERRATUM_2067961
> > +	MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2),
> > +#endif
> > +#ifdef CONFIG_ARM64_ERRATUM_2054223
> > +	MIDR_ALL_VERSIONS(MIDR_CORTEX_A710),
> > +#endif
> > +	{},
> > +};
> > +#endif	/* CONFIG_ARM64_WORKAROUND_TSB_FLUSH_FAILURE */
> > +
> >   const struct arm64_cpu_capabilities arm64_errata[] = {
> >   #ifdef CONFIG_ARM64_WORKAROUND_CLEAN_CACHE
> >   	{
> > @@ -558,6 +570,13 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
> >   		.type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
> >   		CAP_MIDR_RANGE_LIST(trbe_overwrite_fill_mode_cpus),
> >   	},
> > +#endif
> > +#ifdef CONFIG_ARM64_WORKAROUND_TSB_FLUSH_FAILRE
>
> You still haven't fixed this typo...

Sorry about that. I thought it was about selecting the
Kconfig entries, which was fixed. I will fix this.

> Seriously, I get compile warnings from this -- are you not seeing them?

No, I don't get any warnings. Is there something that I am missing ?

--8>--

suzuki@ewhatever:coresight$ grep "WERROR\|TSB" .config
CONFIG_WERROR=y
CONFIG_ARM64_WORKAROUND_TSB_FLUSH_FAILURE=y
suzuki@ewhatever:coresight$ grep TSB arch/arm64/kernel/cpu_errata.c
#ifdef CONFIG_ARM64_WORKAROUND_TSB_FLUSH_FAILURE
#endif  /* CONFIG_ARM64_WORKAROUND_TSB_FLUSH_FAILURE */
#ifdef CONFIG_ARM64_WORKAROUND_TSB_FLUSH_FAILRE
                .capability = ARM64_WORKAROUND_TSB_FLUSH_FAILURE,


suzuki@ewhatever:coresight$ touch arch/arm64/kernel/cpu_errata.c
suzuki@ewhatever:coresight$ make -j16
  CALL    scripts/atomic/check-atomics.sh
  CALL    scripts/checksyscalls.sh
  CHK     include/generated/compile.h
  CC      arch/arm64/kernel/cpu_errata.o
  AR      arch/arm64/kernel/built-in.a
  AR      arch/arm64/built-in.a
  GEN     .version
  CHK     include/generated/compile.h
  UPD     include/generated/compile.h
  CC      init/version.o
  AR      init/built-in.a
  LD      vmlinux.o
  MODPOST vmlinux.symvers
  MODINFO modules.builtin.modinfo
  GEN     modules.builtin
  LD      .tmp_vmlinux.kallsyms1
  KSYMS   .tmp_vmlinux.kallsyms1.S
  AS      .tmp_vmlinux.kallsyms1.S
  LD      .tmp_vmlinux.kallsyms2
  KSYMS   .tmp_vmlinux.kallsyms2.S
  AS      .tmp_vmlinux.kallsyms2.S
  LD      vmlinux
  SORTTAB vmlinux
  SYSMAP  System.map
  MODPOST modules-only.symvers
  OBJCOPY arch/arm64/boot/Image
  GEN     Module.symvers
  GZIP    arch/arm64/boot/Image.gz

Suzuki
> Will