From 9bbafce2eec190ef7e44b0eb1095ba17ce6ad3af Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Wed, 26 Mar 2008 19:02:47 +0900 Subject: sh: Fix occasional FPU register corruption under preempt. Presently with preempt enabled there's the possibility to be preempted after the TIF_USEDFPU test and the register save, leading to bogus state post-__switch_to(). Use an explicit preempt_disable()/enable() pair around unlazy_fpu()/clear_fpu() to avoid this. Follows the x86 change. Reported-by: Takuo Koguchi Signed-off-by: Paul Mundt --- include/asm-sh/fpu.h | 32 ++++++++++++++++++-------------- 1 file changed, 18 insertions(+), 14 deletions(-) (limited to 'include/asm-sh/fpu.h') diff --git a/include/asm-sh/fpu.h b/include/asm-sh/fpu.h index f8429880a27..f89abf5920d 100644 --- a/include/asm-sh/fpu.h +++ b/include/asm-sh/fpu.h @@ -1,9 +1,8 @@ #ifndef __ASM_SH_FPU_H #define __ASM_SH_FPU_H -#define SR_FD 0x00008000 - #ifndef __ASSEMBLY__ +#include #include #ifdef CONFIG_SH_FPU @@ -28,18 +27,23 @@ extern void save_fpu(struct task_struct *__tsk, struct pt_regs *regs); extern int do_fpu_inst(unsigned short, struct pt_regs *); -#define unlazy_fpu(tsk, regs) do { \ - if (test_tsk_thread_flag(tsk, TIF_USEDFPU)) { \ - save_fpu(tsk, regs); \ - } \ -} while (0) - -#define clear_fpu(tsk, regs) do { \ - if (test_tsk_thread_flag(tsk, TIF_USEDFPU)) { \ - clear_tsk_thread_flag(tsk, TIF_USEDFPU); \ - release_fpu(regs); \ - } \ -} while (0) +static inline void unlazy_fpu(struct task_struct *tsk, struct pt_regs *regs) +{ + preempt_disable(); + if (test_tsk_thread_flag(tsk, TIF_USEDFPU)) + save_fpu(tsk, regs); + preempt_enable(); +} + +static inline void clear_fpu(struct task_struct *tsk, struct pt_regs *regs) +{ + preempt_disable(); + if (test_tsk_thread_flag(tsk, TIF_USEDFPU)) { + clear_tsk_thread_flag(tsk, TIF_USEDFPU); + release_fpu(regs); + } + preempt_enable(); +} #endif /* __ASSEMBLY__ */ -- cgit v1.2.3