On 1/7/2025 12:05 PM, Douglas Anderson wrote:
> Qualcomm Kryo 400-series Gold cores have a derivative of an ARM Cortex
> A76 in them. Since A76 needs Spectre mitigation via looping then the
> Kyro 400-series Gold cores also need Spectre mitigation via looping.
>
> Qualcomm has confirmed that the proper "k" value for Kryo 400-series
> Gold cores is 24.
>
> Fixes: 558c303c9734 ("arm64: Mitigate spectre style branch history side channels")
> Cc: stable@xxxxxxxxxxxxxxx
> Cc: Scott Bauer <sbauer@xxxxxxxxxxx>
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
>
> Changes in v4:
> - Re-added QCOM_KRYO_4XX_GOLD k24 patch after Qualcomm confirmed.
>
> Changes in v3:
> - Removed QCOM_KRYO_4XX_GOLD k24 patch.
>
> Changes in v2:
> - Slight change to wording and notes of KRYO_4XX_GOLD patch
>
> arch/arm64/kernel/proton-pack.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c
> index da53722f95d4..e149efadff20 100644
> --- a/arch/arm64/kernel/proton-pack.c
> +++ b/arch/arm64/kernel/proton-pack.c
> @@ -866,6 +866,7 @@ u8 spectre_bhb_loop_affected(int scope)
> MIDR_ALL_VERSIONS(MIDR_CORTEX_A76),
> MIDR_ALL_VERSIONS(MIDR_CORTEX_A77),
> MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1),
> + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_GOLD),
> {},
> };
> static const struct midr_range spectre_bhb_k11_list[] = {
LGTM. Sorry for the delay.
Acked-by: Trilok Soni <quic_tsoni@xxxxxxxxxxx>
--
---Trilok Soni
