From 74158a8cad79d2f5dcf71508993664c5cfcbfa3c Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Fri, 28 Jul 2023 00:08:24 +0000 Subject: KVM: arm64: Skip instruction after emulating write to TCR_EL1 Whelp, this is embarrassing. Since commit 082fdfd13841 ("KVM: arm64: Prevent guests from enabling HA/HD on Ampere1") KVM traps writes to TCR_EL1 on AmpereOne to work around an erratum in the unadvertised HAFDBS implementation, preventing the guest from enabling the feature. Unfortunately, I failed virtualization 101 when working on that change, and forgot to advance PC after instruction emulation. Do the right thing and skip the MSR instruction after emulating the write. Fixes: 082fdfd13841 ("KVM: arm64: Prevent guests from enabling HA/HD on Ampere1") Acked-by: Marc Zyngier Link: https://lore.kernel.org/r/20230728000824.3848025-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton --- arch/arm64/kvm/hyp/include/hyp/switch.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm64/kvm/hyp/include/hyp/switch.h') diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 4bddb8541bec..34f222af6165 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -457,6 +457,7 @@ static bool handle_ampere1_tcr(struct kvm_vcpu *vcpu) */ val &= ~(TCR_HD | TCR_HA); write_sysreg_el1(val, SYS_TCR); + __kvm_skip_instr(vcpu); return true; } -- cgit