2022-08-09 05:03:25

by Zenghui Yu

[permalink] [raw]
Subject: [PATCH] arm64: Fix match_list for erratum 1286807 on Arm Cortex-A76

Since commit 51f559d66527 ("arm64: Enable repeat tlbi workaround on KRYO4XX
gold CPUs"), we failed to detect erratum 1286807 on Cortex-A76 because its
entry in arm64_repeat_tlbi_list[] was accidently corrupted by this commit.

Fix this issue by creating a separate entry for Kryo4xx Gold.

Fixes: 51f559d66527 ("arm64: Enable repeat tlbi workaround on KRYO4XX gold CPUs")
Cc: Shreyas K K <[email protected]>
Signed-off-by: Zenghui Yu <[email protected]>
---
arch/arm64/kernel/cpu_errata.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 7e6289e709fc..0f7e9087d900 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -208,6 +208,8 @@ static const struct arm64_cpu_capabilities arm64_repeat_tlbi_list[] = {
#ifdef CONFIG_ARM64_ERRATUM_1286807
{
ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 3, 0),
+ },
+ {
/* Kryo4xx Gold (rcpe to rfpe) => (r0p0 to r3p0) */
ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
},
--
2.33.0


2022-08-09 06:36:27

by Marc Zyngier

[permalink] [raw]
Subject: Re: [PATCH] arm64: Fix match_list for erratum 1286807 on Arm Cortex-A76

On 2022-08-09 05:38, Zenghui Yu wrote:
> Since commit 51f559d66527 ("arm64: Enable repeat tlbi workaround on
> KRYO4XX
> gold CPUs"), we failed to detect erratum 1286807 on Cortex-A76 because
> its
> entry in arm64_repeat_tlbi_list[] was accidently corrupted by this
> commit.
>
> Fix this issue by creating a separate entry for Kryo4xx Gold.
>
> Fixes: 51f559d66527 ("arm64: Enable repeat tlbi workaround on KRYO4XX
> gold CPUs")
> Cc: Shreyas K K <[email protected]>
> Signed-off-by: Zenghui Yu <[email protected]>
> ---
> arch/arm64/kernel/cpu_errata.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/arm64/kernel/cpu_errata.c
> b/arch/arm64/kernel/cpu_errata.c
> index 7e6289e709fc..0f7e9087d900 100644
> --- a/arch/arm64/kernel/cpu_errata.c
> +++ b/arch/arm64/kernel/cpu_errata.c
> @@ -208,6 +208,8 @@ static const struct arm64_cpu_capabilities
> arm64_repeat_tlbi_list[] = {
> #ifdef CONFIG_ARM64_ERRATUM_1286807
> {
> ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 3, 0),
> + },
> + {
> /* Kryo4xx Gold (rcpe to rfpe) => (r0p0 to r3p0) */
> ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
> },

Ouch. It isn't the first time we end-up with this sort
of thing, and I wonder whether we should restructure
the ERRATA_MIDR_* macros to prevent this sort of
accidental override...

Anyway, thanks for spotting it!

Cc: [email protected]
Acked-by: Marc Zyngier <[email protected]>

M.
--
Jazz is not dead. It just smells funny...

2022-08-09 08:59:26

by Will Deacon

[permalink] [raw]
Subject: Re: [PATCH] arm64: Fix match_list for erratum 1286807 on Arm Cortex-A76

On Tue, Aug 09, 2022 at 07:08:07AM +0100, Marc Zyngier wrote:
> On 2022-08-09 05:38, Zenghui Yu wrote:
> > Since commit 51f559d66527 ("arm64: Enable repeat tlbi workaround on
> > KRYO4XX
> > gold CPUs"), we failed to detect erratum 1286807 on Cortex-A76 because
> > its
> > entry in arm64_repeat_tlbi_list[] was accidently corrupted by this
> > commit.
> >
> > Fix this issue by creating a separate entry for Kryo4xx Gold.
> >
> > Fixes: 51f559d66527 ("arm64: Enable repeat tlbi workaround on KRYO4XX
> > gold CPUs")
> > Cc: Shreyas K K <[email protected]>
> > Signed-off-by: Zenghui Yu <[email protected]>
> > ---
> > arch/arm64/kernel/cpu_errata.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > diff --git a/arch/arm64/kernel/cpu_errata.c
> > b/arch/arm64/kernel/cpu_errata.c
> > index 7e6289e709fc..0f7e9087d900 100644
> > --- a/arch/arm64/kernel/cpu_errata.c
> > +++ b/arch/arm64/kernel/cpu_errata.c
> > @@ -208,6 +208,8 @@ static const struct arm64_cpu_capabilities
> > arm64_repeat_tlbi_list[] = {
> > #ifdef CONFIG_ARM64_ERRATUM_1286807
> > {
> > ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 3, 0),
> > + },
> > + {
> > /* Kryo4xx Gold (rcpe to rfpe) => (r0p0 to r3p0) */
> > ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
> > },
>
> Ouch. It isn't the first time we end-up with this sort
> of thing, and I wonder whether we should restructure
> the ERRATA_MIDR_* macros to prevent this sort of
> accidental override...

Agreed. I think we may have gone a bit too far with the macros in
cpu_errata.c and cpufeature.c. Although the files would be larger, I think
it would be clearer if we removed some of the abstractions and forced this
stuff to be spelled out each time.

> Anyway, thanks for spotting it!
>
> Cc: [email protected]
> Acked-by: Marc Zyngier <[email protected]>

I'll queue this as a fix at -rc1 along with any other fixes which come in.

Will

2022-08-17 15:32:09

by Will Deacon

[permalink] [raw]
Subject: Re: [PATCH] arm64: Fix match_list for erratum 1286807 on Arm Cortex-A76

On Tue, 9 Aug 2022 12:38:48 +0800, Zenghui Yu wrote:
> Since commit 51f559d66527 ("arm64: Enable repeat tlbi workaround on KRYO4XX
> gold CPUs"), we failed to detect erratum 1286807 on Cortex-A76 because its
> entry in arm64_repeat_tlbi_list[] was accidently corrupted by this commit.
>
> Fix this issue by creating a separate entry for Kryo4xx Gold.
>
>
> [...]

Applied to arm64 (for-next/fixes), thanks!

[1/1] arm64: Fix match_list for erratum 1286807 on Arm Cortex-A76
https://git.kernel.org/arm64/c/5e1e087457c9

Cheers,
--
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev