arm64: errata: Add KRYO 2XX/3XX/4XX silver cores to Spectre BHB safe list

commit 0c9fc6e652cd5aed48c5f700c32b7642bea7f453 upstream.

Qualcomm has confirmed that, much like Cortex A53 and A55, KRYO
2XX/3XX/4XX silver cores are unaffected by Spectre BHB. Add them to
the safe list.

Fixes: 558c303c9734 ("arm64: Mitigate spectre style branch history side channels")
Cc: stable@vger.kernel.org
Cc: Scott Bauer <sbauer@quicinc.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Trilok Soni <quic_tsoni@quicinc.com>
Link: https://lore.kernel.org/r/20250107120555.v4.3.Iab8dbfb5c9b1e143e7a29f410bce5f9525a0ba32@changeid
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c
index 17aa836fe46defb8e5e99356ab2e1278db1e5bd4..89405be53d8fc0cf9d5dfcb746de4a472cc69a70 100644 (file)
--- a/arch/arm64/kernel/proton-pack.c
+++ b/arch/arm64/kernel/proton-pack.c
@@ -854,6 +854,9 @@ static bool is_spectre_bhb_safe(int scope)
                MIDR_ALL_VERSIONS(MIDR_CORTEX_A510),
                MIDR_ALL_VERSIONS(MIDR_CORTEX_A520),
                MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53),
+               MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER),
+               MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER),
+               MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER),
                {},
        };
        static bool all_safe = true;