This is a note to let you know that I've just added the patch titled
x86/fpu: Fix get_xsave_addr() behavior under virtualization
to the 4.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-fpu-fix-get_xsave_addr-behavior-under-virtualization.patch
and it can be found in the queue-4.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a05917b6ba9dc9a95fc42bdcbe3a875e8ad83935 Mon Sep 17 00:00:00 2001
From: Huaitong Han <huaitong.han@xxxxxxxxx>
Date: Fri, 6 Nov 2015 17:00:23 +0800
Subject: x86/fpu: Fix get_xsave_addr() behavior under virtualization
From: Huaitong Han <huaitong.han@xxxxxxxxx>
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 <huaitong.han@xxxxxxxxx>
Reviewed-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Quentin Casasnovas <quentin.casasnovas@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: dave.hansen@xxxxxxxxx
Link: http://lkml.kernel.org/r/1446800423-21622-1-git-send-email-huaitong.han@xxxxxxxxx
[ Tidied up the changelog. ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
Patches currently in stable-queue which might be from huaitong.han@xxxxxxxxx are
queue-4.2/x86-fpu-fix-get_xsave_addr-behavior-under-virtualization.patch
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