diff options
| author | Oliver Upton <oliver.upton@linux.dev> | 2024-06-21 22:40:44 +0000 |
|---|---|---|
| committer | Oliver Upton <oliver.upton@linux.dev> | 2024-06-22 17:21:50 +0000 |
| commit | 33d85a93c6c3c0c1fc2d168ee5a9ae604c439fa7 (patch) | |
| tree | deba6035c4b6170936bd401ad559d5ca6ecf79d9 /arch/arm64/kvm/nested.c | |
| parent | 11a31be88fb6191f2584a0b6364b11e21d068685 (diff) | |
KVM: arm64: nv: Unfudge ID_AA64PFR0_EL1 masking
Marc reports that L1 VMs aren't booting with the NV series applied to
today's kvmarm/next. After bisecting the issue, it appears that
44241f34fac9 ("KVM: arm64: nv: Use accessors for modifying ID
registers") is to blame.
Poking around at the issue a bit further, it'd appear that the value for
ID_AA64PFR0_EL1 is complete garbage, as 'val' still contains the value
we set ID_AA64ISAR1_EL1 to.
Fix the read-modify-write pattern to actually use ID_AA64PFR0_EL1 as the
starting point. Excuse me as I return to my shame cube.
Reported-by: Marc Zyngier <maz@kernel.org>
Fixes: 44241f34fac9 ("KVM: arm64: nv: Use accessors for modifying ID registers")
Acked-by: Marc Zyngier <maz@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240621224044.2465901-1-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Diffstat (limited to 'arch/arm64/kvm/nested.c')
| -rw-r--r-- | arch/arm64/kvm/nested.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c index 44085c13e673..794ed18c0537 100644 --- a/arch/arm64/kvm/nested.c +++ b/arch/arm64/kvm/nested.c @@ -40,7 +40,7 @@ static void limit_nv_id_regs(struct kvm *kvm) kvm_set_vm_id_reg(kvm, SYS_ID_AA64ISAR1_EL1, val); /* No AMU, MPAM, S-EL2, RAS or SVE */ - kvm_read_vm_id_reg(kvm, SYS_ID_AA64PFR0_EL1); + val = kvm_read_vm_id_reg(kvm, SYS_ID_AA64PFR0_EL1); val &= ~(GENMASK_ULL(55, 52) | NV_FTR(PFR0, AMU) | NV_FTR(PFR0, MPAM) | |