From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934158AbdKAV2H (ORCPT ); Wed, 1 Nov 2017 17:28:07 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:35324 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934131AbdKAV2D (ORCPT ); Wed, 1 Nov 2017 17:28:03 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Greg Kroah-Hartman , Willy Tarreau Subject: [PATCH 3.10 090/139] kvm: async_pf: fix rcu_irq_enter() with irqs enabled Date: Wed, 1 Nov 2017 22:26:31 +0100 Message-Id: <1509571600-4858-41-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1509571600-4858-1-git-send-email-w@1wt.eu> References: <1509571159-4405-1-git-send-email-w@1wt.eu> <1509571600-4858-1-git-send-email-w@1wt.eu> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Paolo Bonzini commit bbaf0e2b1c1b4f88abd6ef49576f0efb1734eae5 upstream. native_safe_halt enables interrupts, and you just shouldn't call rcu_irq_enter() with interrupts enabled. Reorder the call with the following local_irq_disable() to respect the invariant. Reported-by: Ross Zwisler Signed-off-by: Paolo Bonzini Acked-by: Paul E. McKenney Tested-by: Wanpeng Li Signed-off-by: Radim Krčmář Signed-off-by: Greg Kroah-Hartman Signed-off-by: Willy Tarreau --- arch/x86/kernel/kvm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index c4ff2a9..c95ece9 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -159,8 +159,8 @@ void kvm_async_pf_task_wait(u32 token) */ rcu_irq_exit(); native_safe_halt(); - rcu_irq_enter(); local_irq_disable(); + rcu_irq_enter(); } } if (!n.halted) -- 2.8.0.rc2.1.gbe9624a