Commit 5d6c7de6 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
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KVM: x86: Bail to userspace if emulation of atomic user access faults 



Exit to userspace when emulating an atomic guest access if the CMPXCHG on
the userspace address faults.  Emulating the access as a write and thus
likely treating it as emulated MMIO is wrong, as KVM has already
confirmed there is a valid, writable memslot.

Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20220202004945.2540433-6-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 1c2361f6

arch/x86/kvm/x86.c

+1 −1
Original line number Diff line number Diff line
@@ -7319,7 +7319,7 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, 
	}



	if (r < 0)

		goto emul_write;

		return X86EMUL_UNHANDLEABLE;

	if (r)

		return X86EMUL_CMPXCHG_FAILED;