arm64: Document workaround for Cortex-A72 erratum #853709

We already have a workaround for Cortex-A57 erratum #852523,
but Cortex-A72 r0p0 to r0p2 do suffer from the same issue
(known as erratum #853709).

Let's document the fact that we already handle this.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt
index 4da60b463995464a71c04245e7f90e7ced4f51d2..ccc60324e7388eb5756de1782174246708715c36 100644 (file)
--- a/Documentation/arm64/silicon-errata.txt
+++ b/Documentation/arm64/silicon-errata.txt
@@ -53,6 +53,7 @@ stable kernels.
 | ARM            | Cortex-A57      | #832075         | ARM64_ERRATUM_832075    |
 | ARM            | Cortex-A57      | #852523         | N/A                     |
 | ARM            | Cortex-A57      | #834220         | ARM64_ERRATUM_834220    |
+| ARM            | Cortex-A72      | #853709         | N/A                     |
 | ARM            | MMU-500         | #841119,#826419 | N/A                     |
 |                |                 |                 |                         |
 | Cavium         | ThunderX ITS    | #22375, #24313  | CAVIUM_ERRATUM_22375    |

diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index ae7855f16ec2966f6cde3c2639fe3af360e9a676..5a84b45626032ea1260eea2536da42231dcbfa4f 100644 (file)
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -256,7 +256,7 @@ static int __hyp_text __guest_run(struct kvm_vcpu *vcpu)
 
        /*
         * We must restore the 32-bit state before the sysregs, thanks
-        * to Cortex-A57 erratum #852523.
+        * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72).
         */
        __sysreg32_restore_state(vcpu);
        __sysreg_restore_guest_state(guest_ctxt);