From 543f2a3382bd7abd7380903518c61f00c7c87577 Mon Sep 17 00:00:00 2001 From: Chuck Ebbert <76306.1226@compuserve.com> Date: Sat, 29 Apr 2006 14:07:49 -0400 Subject: [PATCH] [PATCH] i386: fix broken FP exception handling The FXSAVE information leak patch introduced a bug in FP exception handling: it clears FP exceptions only when there are already none outstanding. Mikael Pettersson reported that causes problems with the Erlang runtime and has tested this fix. Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com> Acked-by: Mikael Pettersson Signed-off-by: Linus Torvalds --- include/asm-i386/i387.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/asm-i386/i387.h b/include/asm-i386/i387.h index 7b1f01191e70..bc1d6edae1ed 100644 --- a/include/asm-i386/i387.h +++ b/include/asm-i386/i387.h @@ -58,13 +58,13 @@ static inline void __save_init_fpu( struct task_struct *tsk ) alternative_input( "fnsave %[fx] ;fwait;" GENERIC_NOP8 GENERIC_NOP4, "fxsave %[fx]\n" - "bt $7,%[fsw] ; jc 1f ; fnclex\n1:", + "bt $7,%[fsw] ; jnc 1f ; fnclex\n1:", X86_FEATURE_FXSR, [fx] "m" (tsk->thread.i387.fxsave), [fsw] "m" (tsk->thread.i387.fxsave.swd) : "memory"); /* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception is pending. Clear the x87 state here by setting it to fixed - values. __per_cpu_offset[0] is a random variable that should be in L1 */ + values. safe_address is a random variable that should be in L1 */ alternative_input( GENERIC_NOP8 GENERIC_NOP2, "emms\n\t" /* clear stack tags */ -- 2.20.1