From 1f999ab5a1360afc388868cc0ef9afe8edeef3be Mon Sep 17 00:00:00 2001 From: Robert Richter Date: Wed, 21 Jul 2010 19:03:57 +0200 Subject: [PATCH] x86, xsave: Disable xsave in i387 emulation mode xsave is broken for (!HAVE_HWFP). This is the case if config MATH_EMULATION is enabled, 'no387' kernel parameter is set and xsave exists. xsave will not work because x86/math-emu and xsave share the same memory. As this case can be treated as corner case we simply disable xsave then. Signed-off-by: Robert Richter LKML-Reference: <1279731838-1522-7-git-send-email-robert.richter@amd.com> Signed-off-by: H. Peter Anvin --- arch/x86/kernel/i387.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index 1f11f5ce668f..2605c50b11d3 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -67,6 +67,12 @@ static void __cpuinit init_thread_xstate(void) */ if (!HAVE_HWFP) { + /* + * Disable xsave as we do not support it if i387 + * emulation is enabled. + */ + setup_clear_cpu_cap(X86_FEATURE_XSAVE); + setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT); xstate_size = sizeof(struct i387_soft_struct); return; }