From 76deabd1867d6d2895152f31fdec819e3505738b Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Mon, 11 May 2015 17:52:19 +0200 Subject: [PATCH] sched/preempt, MIPS: Properly lock access to the FPU Let's always disable preemption and pagefaults when locking the fpu, so we can be sure that the owner won't change in between. This is a preparation for pagefault_disable() not touching preemption anymore. Reviewed-and-tested-by: Thomas Gleixner Signed-off-by: David Hildenbrand Signed-off-by: Peter Zijlstra (Intel) Cc: David.Laight@ACULAB.COM Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: airlied@linux.ie Cc: akpm@linux-foundation.org Cc: benh@kernel.crashing.org Cc: bigeasy@linutronix.de Cc: borntraeger@de.ibm.com Cc: daniel.vetter@intel.com Cc: heiko.carstens@de.ibm.com Cc: herbert@gondor.apana.org.au Cc: hocko@suse.cz Cc: hughd@google.com Cc: mst@redhat.com Cc: paulus@samba.org Cc: ralf@linux-mips.org Cc: schwidefsky@de.ibm.com Cc: yang.shi@windriver.com Link: http://lkml.kernel.org/r/1431359540-32227-15-git-send-email-dahi@linux.vnet.ibm.com Signed-off-by: Ingo Molnar --- arch/mips/kernel/signal-common.h | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/arch/mips/kernel/signal-common.h b/arch/mips/kernel/signal-common.h index 06805e09bcd3..0b85f827cd18 100644 --- a/arch/mips/kernel/signal-common.h +++ b/arch/mips/kernel/signal-common.h @@ -28,12 +28,7 @@ extern void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, 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 +#define lock_fpu_owner() ({ preempt_disable(); pagefault_disable(); }) +#define unlock_fpu_owner() ({ pagefault_enable(); preempt_enable(); }) #endif /* __SIGNAL_COMMON_H */