path: root/arch/x86/kernel/process_64.c
diff options
authorLinus Torvalds <torvalds@linux-foundation.org>2012-02-20 10:24:09 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-02-20 10:24:09 -0800
commitcea20ca3f3181fc36788a15bc65d1062b96a0a6c (patch)
tree86c646c0d228d1fe265536b81d86af406ff92c8e /arch/x86/kernel/process_64.c
parentb01543dfe67bb1d191998e90d20534dc354de059 (diff)
i387: fix up some fpu_counter confusion
This makes sure we clear the FPU usage counter for newly created tasks, just so that we start off in a known state (for example, don't try to preload the FPU state on the first task switch etc). It also fixes a thinko in when we increment the fpu_counter at task switch time, introduced by commit 34ddc81a230b ("i387: re-introduce FPU state preloading at context switch time"). We should increment the *new* task fpu_counter, not the old task, and only if we decide to use that state (whether lazily or preloaded). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86/kernel/process_64.c')
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 1fd94bc4279d..8ad880b3bc1c 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -286,6 +286,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
set_tsk_thread_flag(p, TIF_FORK);
+ p->fpu_counter = 0;
p->thread.io_bitmap_ptr = NULL;
savesegment(gs, p->thread.gsindex);

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