From 4dfc896e90359df04c80da5ab08ec31e87846c43 Mon Sep 17 00:00:00 2001 From: Jiri Kosina Date: Wed, 28 Mar 2007 18:12:34 +0200 Subject: [PATCH] oprofile: fix potential deadlock on oprofilefs_lock nmi_cpu_setup() is called from hardirq context and acquires oprofilefs_lock. alloc_event_buffer() and oprofilefs_ulong_from_user() acquire this lock without disabling irqs, which could deadlock. Signed-off-by: Jiri Kosina Signed-off-by: Linus Torvalds --- drivers/oprofile/event_buffer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/oprofile/event_buffer.c') diff --git a/drivers/oprofile/event_buffer.c b/drivers/oprofile/event_buffer.c index 00e937e9240..e7fbac52993 100644 --- a/drivers/oprofile/event_buffer.c +++ b/drivers/oprofile/event_buffer.c @@ -70,11 +70,12 @@ void wake_up_buffer_waiter(void) int alloc_event_buffer(void) { int err = -ENOMEM; + unsigned long flags; - spin_lock(&oprofilefs_lock); + spin_lock_irqsave(&oprofilefs_lock, flags); buffer_size = fs_buffer_size; buffer_watershed = fs_buffer_watershed; - spin_unlock(&oprofilefs_lock); + spin_unlock_irqrestore(&oprofilefs_lock, flags); if (buffer_watershed >= buffer_size) return -EINVAL; -- cgit v1.2.3