diff options
| author |   Atsushi Nemoto <anemo@mba.ocn.ne.jp> | 2007-04-16 23:19:44 +0900 |
|---|---|---|
| committer |   Ralf Baechle <ralf@linux-mips.org> | 2007-04-20 14:58:37 +0100 |
| commit | faea62346444ce5b1dba8fb5291d95b676522c42 (patch) | |
| tree | d00e53763ca9b145348e5754aaf0cd4dcbb12123 /arch/mips/kernel/signal-common.h | |
| parent | [MIPS] Disallow CpU exception in kernel again. (diff) | |
| download | linux-dev-faea62346444ce5b1dba8fb5291d95b676522c42.tar.xz linux-dev-faea62346444ce5b1dba8fb5291d95b676522c42.zip | |
[MIPS] Retry {save,restore}_fp_context if failed in atomic context.
The save_fp_context()/restore_fp_context() might sleep on accessing
user stack and therefore might lose FPU ownership in middle of them.
If these function failed due to "in_atomic" test in do_page_fault,
touch the sigcontext area in non-atomic context and retry these
save/restore operation.
This is a replacement of a (broken) fix which was titled "Allow CpU
exception in kernel partially".
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel/signal-common.h')
| -rw-r--r-- | arch/mips/kernel/signal-common.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/mips/kernel/signal-common.h b/arch/mips/kernel/signal-common.h index 297dfcb97524..c0faabd52010 100644 --- a/arch/mips/kernel/signal-common.h +++ b/arch/mips/kernel/signal-common.h @@ -34,4 +34,13 @@ extern int install_sigtramp(unsigned int __user *tramp, unsigned int syscall); /* Check and clear pending FPU exceptions in saved CSR */ extern int fpcsr_pending(unsigned int __user *fpcsr); +/* Make sure we will not lose FPU ownership */ +#ifdef CONFIG_PREEMPT +#define lock_fpu_owner() preempt_disable() +#define unlock_fpu_owner() preempt_enable() +#else +#define lock_fpu_owner() pagefault_disable() +#define unlock_fpu_owner() pagefault_enable() +#endif + #endif /* __SIGNAL_COMMON_H */ |