From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Huaitong Han , Dave Hansen , Andy Lutomirski , Paolo Bonzini , Borislav Petkov , Fenghua Yu , "H. Peter Anvin" , Linus Torvalds , Oleg Nesterov , Peter Zijlstra , Quentin Casasnovas , Thomas Gleixner , dave.hansen@intel.com, Ingo Molnar Subject: [PATCH 4.2 059/124] x86/fpu: Fix get_xsave_addr() behavior under virtualization Date: Mon, 7 Dec 2015 09:55:49 -0500 Message-Id: <20151207144922.613250381@linuxfoundation.org> In-Reply-To: <20151207144919.656035367@linuxfoundation.org> References: <20151207144919.656035367@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Huaitong Han commit a05917b6ba9dc9a95fc42bdcbe3a875e8ad83935 upstream. KVM uses the get_xsave_addr() function in a different fashion from the native kernel, in that the 'xsave' parameter belongs to guest vcpu, not the currently running task. But 'xsave' is replaced with current task's (host) xsave structure, so get_xsave_addr() will incorrectly return the bad xsave address to KVM. Fix it so that the passed in 'xsave' address is used - as intended originally. Signed-off-by: Huaitong Han Reviewed-by: Dave Hansen Cc: Andy Lutomirski Cc: Paolo Bonzini Cc: Borislav Petkov Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Quentin Casasnovas Cc: Thomas Gleixner Cc: dave.hansen@intel.com Link: http://lkml.kernel.org/r/1446800423-21622-1-git-send-email-huaitong.han@intel.com [ Tidied up the changelog. ] Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/fpu/xstate.c | 1 - 1 file changed, 1 deletion(-) --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -402,7 +402,6 @@ void *get_xsave_addr(struct xregs_state if (!boot_cpu_has(X86_FEATURE_XSAVE)) return NULL; - xsave = ¤t->thread.fpu.state.xsave; /* * We should not ever be requesting features that we * have not enabled. Remember that pcntxt_mask is