From a05917b6ba9dc9a95fc42bdcbe3a875e8ad83935 Mon Sep 17 00:00:00 2001 From: Huaitong Han Date: Fri, 6 Nov 2015 17:00:23 +0800 Subject: [PATCH] x86/fpu: Fix get_xsave_addr() behavior under virtualization 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: 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 --- arch/x86/kernel/fpu/xstate.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 6454f2731b56..70fc312221fc 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -694,7 +694,6 @@ void *get_xsave_addr(struct xregs_state *xsave, int xstate_feature) 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 -- 2.20.1