diff options
author | Paul Mundt <lethal@linux-sh.org> | 2008-03-26 19:02:47 +0900 |
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committer | Paul Mundt <lethal@linux-sh.org> | 2008-03-26 19:02:47 +0900 |
commit | 9bbafce2eec190ef7e44b0eb1095ba17ce6ad3af (patch) | |
tree | 8deae79efc43d39763bdba8ca9b670e6a1782859 /include/asm-sh/fpu.h | |
parent | 05dda977f2574c3341abef9b74c27d2b362e1e3a (diff) |
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 <takuo.koguchi.sw@hitachi.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'include/asm-sh/fpu.h')
-rw-r--r-- | include/asm-sh/fpu.h | 32 |
1 files changed, 18 insertions, 14 deletions
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 <linux/preempt.h> #include <asm/ptrace.h> #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__ */ |