arm64: fix midr range for Cortex-A57 erratum 832075

commit 6d1966dfd6e0ad2f8aa4b664ae1a62e33abe1998 upstream.

Register MIDR_EL1 is masked to get variant and revision fields, then
compared against midr_range_min and midr_range_max when checking
whether CPU is affected by any particular erratum. However, variant
and revision fields in MIDR_EL1 are separated by 16 bits, so the min
and max of midr range should be constructed accordingly, otherwise
the patch will not be applied when variant field is non-0.

Acked-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Bo Yan <byan@nvidia.com>
[will: use MIDR_VARIANT_SHIFT to construct upper bound]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index fa62637e63a8c6e7498ba7957395b3030583bb02..7c4849489515d672cca4570c4e8c465352ba8223 100644 (file)
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -88,7 +88,8 @@ struct arm64_cpu_capabilities arm64_errata[] = {
        /* Cortex-A57 r0p0 - r1p2 */
                .desc = "ARM erratum 832075",
                .capability = ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE,
-               MIDR_RANGE(MIDR_CORTEX_A57, 0x00, 0x12),
+               MIDR_RANGE(MIDR_CORTEX_A57, 0x00,
+                          (1 << MIDR_VARIANT_SHIFT) | 2),
        },
 #endif
        {