diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2021-11-12 10:53:41 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-11-18 21:17:14 +0300 |
| commit | fb58e9a26c3ce0278d8118fc2a70e6d528967f42 (patch) | |
| tree | c4160f21c55e1c673610ff746e8cfd84cb6b2c5e /arch/x86 | |
| parent | d5e79d872babb12a1376bc07b4abae68d752f66d (diff) | |
| download | linux-fb58e9a26c3ce0278d8118fc2a70e6d528967f42.tar.xz | |
KVM: x86: move guest_pv_has out of user_access section
commit 3e067fd8503d6205aa0c1c8f48f6b209c592d19c upstream.
When UBSAN is enabled, the code emitted for the call to guest_pv_has
includes a call to __ubsan_handle_load_invalid_value. objtool
complains that this call happens with UACCESS enabled; to avoid
the warning, pull the calls to user_access_begin into both arms
of the "if" statement, after the check for guest_pv_has.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/x86.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 54a45496b59e..3de93d4bf16b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3227,9 +3227,6 @@ static void record_steal_time(struct kvm_vcpu *vcpu) } st = (struct kvm_steal_time __user *)ghc->hva; - if (!user_access_begin(st, sizeof(*st))) - return; - /* * Doing a TLB flush here, on the guest's behalf, can avoid * expensive IPIs. @@ -3238,6 +3235,9 @@ static void record_steal_time(struct kvm_vcpu *vcpu) u8 st_preempted = 0; int err = -EFAULT; + if (!user_access_begin(st, sizeof(*st))) + return; + asm volatile("1: xchgb %0, %2\n" "xor %1, %1\n" "2:\n" @@ -3260,6 +3260,9 @@ static void record_steal_time(struct kvm_vcpu *vcpu) if (!user_access_begin(st, sizeof(*st))) goto dirty; } else { + if (!user_access_begin(st, sizeof(*st))) + return; + unsafe_put_user(0, &st->preempted, out); vcpu->arch.st.preempted = 0; } |