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| author | Suresh Siddha <suresh.b.siddha@intel.com> | 2012-08-24 23:12:57 +0200 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-09-19 00:52:05 +0200 |
| commit | e962591749dfd4df9fea2c530ed7a3cfed50e5aa (patch) | |
| tree | 9465f4181ef0431c03c1dcd92674b028f37a9d3e | |
| parent | x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels (diff) | |
| download | linux-e962591749dfd4df9fea2c530ed7a3cfed50e5aa.tar.xz linux-e962591749dfd4df9fea2c530ed7a3cfed50e5aa.zip | |
x86, fpu: drop_fpu() before restoring new state from sigframe
No need to save the state with unlazy_fpu(), that is about to get overwritten
by the state from the signal frame. Instead use drop_fpu() and continue
to restore the new state.
Also fold the stop_fpu_preload() into drop_fpu().
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1345842782-24175-2-git-send-email-suresh.b.siddha@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| -rw-r--r-- | arch/x86/include/asm/fpu-internal.h | 7 | ||||
| -rw-r--r-- | arch/x86/kernel/xsave.c | 8 |
2 files changed, 4 insertions, 11 deletions
diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h index 4fbb4195bc63..78169d133d4c 100644 --- a/arch/x86/include/asm/fpu-internal.h +++ b/arch/x86/include/asm/fpu-internal.h @@ -448,17 +448,12 @@ static inline void save_init_fpu(struct task_struct *tsk) preempt_enable(); } -static inline void stop_fpu_preload(struct task_struct *tsk) -{ - tsk->fpu_counter = 0; -} - static inline void drop_fpu(struct task_struct *tsk) { /* * Forget coprocessor state.. */ - stop_fpu_preload(tsk); + tsk->fpu_counter = 0; preempt_disable(); __drop_fpu(tsk); preempt_enable(); diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c index 0923d27f23df..07ddc870640b 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -382,16 +382,14 @@ int __restore_xstate_sig(void __user *buf, void __user *buf_fx, int size) struct xsave_struct *xsave = &tsk->thread.fpu.state->xsave; struct user_i387_ia32_struct env; - stop_fpu_preload(tsk); - unlazy_fpu(tsk); + drop_fpu(tsk); if (__copy_from_user(xsave, buf_fx, state_size) || - __copy_from_user(&env, buf, sizeof(env))) { - drop_fpu(tsk); + __copy_from_user(&env, buf, sizeof(env))) return -1; - } sanitize_restored_xstate(tsk, &env, xstate_bv, fx_only); + set_used_math(); } else { /* * For 64-bit frames and 32-bit fsave frames, restore the user |