linux-kernel - [PATCH 7/7] KVM: x86: Cleanup of rflags.rf cleaning

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Message-Id: <1405942650-22589-8-git-send-email-namit@cs.technion.ac.il>
Date:	Mon, 21 Jul 2014 14:37:30 +0300
From:	Nadav Amit <namit@...technion.ac.il>
To:	pbonzini@...hat.com
Cc:	tglx@...utronix.de, mingo@...hat.com, hpa@...or.com,
	x86@...nel.org, gleb@...nel.org, linux-kernel@...r.kernel.org,
	Nadav Amit <namit@...technion.ac.il>
Subject: [PATCH 7/7] KVM: x86: Cleanup of rflags.rf cleaning

RFLAGS.RF was cleaned in several functions (e.g., syscall) in the x86 emulator.
Now that we clear it before the execution of an instruction in the emulator, we
can remove the specific cleanup of RFLAGS.RF.

Signed-off-by: Nadav Amit <namit@...technion.ac.il>
---
 arch/x86/kvm/emulate.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 189b8bd8..8d41556 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2211,7 +2211,7 @@ static int em_syscall(struct x86_emulate_ctxt *ctxt)
 	*reg_write(ctxt, VCPU_REGS_RCX) = ctxt->_eip;
 	if (efer & EFER_LMA) {
 #ifdef CONFIG_X86_64
-		*reg_write(ctxt, VCPU_REGS_R11) = ctxt->eflags & ~EFLG_RF;
+		*reg_write(ctxt, VCPU_REGS_R11) = ctxt->eflags;
 
 		ops->get_msr(ctxt,
 			     ctxt->mode == X86EMUL_MODE_PROT64 ?
@@ -2219,14 +2219,14 @@ static int em_syscall(struct x86_emulate_ctxt *ctxt)
 		ctxt->_eip = msr_data;
 
 		ops->get_msr(ctxt, MSR_SYSCALL_MASK, &msr_data);
-		ctxt->eflags &= ~(msr_data | EFLG_RF);
+		ctxt->eflags &= ~msr_data;
 #endif
 	} else {
 		/* legacy mode */
 		ops->get_msr(ctxt, MSR_STAR, &msr_data);
 		ctxt->_eip = (u32)msr_data;
 
-		ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF);
+		ctxt->eflags &= ~(EFLG_VM | EFLG_IF);
 	}
 
 	return X86EMUL_CONTINUE;
@@ -2275,7 +2275,7 @@ static int em_sysenter(struct x86_emulate_ctxt *ctxt)
 		break;
 	}
 
-	ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF);
+	ctxt->eflags &= ~(EFLG_VM | EFLG_IF);
 	cs_sel = (u16)msr_data;
 	cs_sel &= ~SELECTOR_RPL_MASK;
 	ss_sel = cs_sel + 8;
-- 
1.9.1

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