diff options
| author | Mark Brown <broonie@kernel.org> | 2022-11-15 09:46:33 +0000 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2022-11-29 15:01:56 +0000 |
| commit | 93ae6b01bafee8fa385aa25ee7ebdb40057f6abe (patch) | |
| tree | fbe474a34317174ae99e4e7be723ebae1e386288 /arch/arm64/kvm | |
| parent | f0c4d9fc9cc9462659728d168387191387e903cc (diff) | |
KVM: arm64: Discard any SVE state when entering KVM guests
Since 8383741ab2e773a99 (KVM: arm64: Get rid of host SVE tracking/saving)
KVM has not tracked the host SVE state, relying on the fact that we
currently disable SVE whenever we perform a syscall. This may not be true
in future since performance optimisation may result in us keeping SVE
enabled in order to avoid needing to take access traps to reenable it.
Handle this by clearing TIF_SVE and converting the stored task state to
FPSIMD format when preparing to run the guest. This is done with a new
call fpsimd_kvm_prepare() to keep the direct state manipulation
functions internal to fpsimd.c.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221115094640.112848-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/kvm')
| -rw-r--r-- | arch/arm64/kvm/fpsimd.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c index ec8e4494873d..51ca78b31b95 100644 --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -75,11 +75,12 @@ int kvm_arch_vcpu_run_map_fp(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu) { BUG_ON(!current->mm); - BUG_ON(test_thread_flag(TIF_SVE)); if (!system_supports_fpsimd()) return; + fpsimd_kvm_prepare(); + vcpu->arch.fp_state = FP_STATE_HOST_OWNED; vcpu_clear_flag(vcpu, HOST_SVE_ENABLED); |