Commit b9a1ecb9 authored Jul 24, 2014 by Nadav Amit Committed by Paolo Bonzini Jul 24, 2014

KVM: x86: Setting rflags.rf during rep-string emulation

This patch updates RF for rep-string emulation. The flag is set upon the first
iteration, and cleared after the last (if emulated). It is intended to make
sure that if a trap (in future data/io #DB emulation) or interrupt is delivered
to the guest during the rep-string instruction, RF will be set correctly. RF
affects whether instruction breakpoint in the guest is masked.

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

parent c756ad03

arch/x86/kvm/emulate.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -4683,6 +4683,9 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
		goto done;
		}

		if (ctxt->rep_prefix && (ctxt->d & String))
		ctxt->eflags \|= EFLG_RF;
		else
		ctxt->eflags &= ~EFLG_RF;

		if (ctxt->execute) {
		@@ -4824,6 +4827,7 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
		}
		goto done; /* skip rip writeback */
		}
		ctxt->eflags &= ~EFLG_RF;
		}

		ctxt->eip = ctxt->_eip;