Commit 4467c3f1 authored Jul 21, 2014 by Nadav Amit Committed by Paolo Bonzini Jul 21, 2014

KVM: x86: Clear rflags.rf on emulated instructions

When an instruction is emulated RFLAGS.RF should be cleared. KVM previously did
not do so. This patch clears RFLAGS.RF after interception is done. If a fault
occurs during the instruction, RFLAGS.RF will be set by a previous patch. This
patch does not handle the case of traps/interrupts during rep-strings. Traps
are only expected to occur on debug watchpoints, and those are anyhow not
handled by the emulator.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 163b135e

arch/x86/kvm/emulate.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -4640,6 +4640,7 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
		/* All REP prefixes have the same first termination condition */
		if (address_mask(ctxt, reg_read(ctxt, VCPU_REGS_RCX)) == 0) {
		ctxt->eip = ctxt->_eip;
		ctxt->eflags &= ~EFLG_RF;
		goto done;
		}
		}
		@@ -4682,6 +4683,8 @@ special_insn:
		goto done;
		}

		ctxt->eflags &= ~EFLG_RF;

		if (ctxt->execute) {
		if (ctxt->d & Fastop) {
		void (fop)(struct fastop ) = (void *)ctxt->execute;

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