lkdtm: avoid calling lkdtm_do_action() with spinlock held
lkdtm_do_action() may call sleeping functions like kmalloc(), so do not
call it with spin lock held.
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Reviewed-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/misc/lkdtm.c b/drivers/misc/lkdtm.c
index 150cd70..28adefe 100644
--- a/drivers/misc/lkdtm.c
+++ b/drivers/misc/lkdtm.c
@@ -354,6 +354,7 @@
static void lkdtm_handler(void)
{
unsigned long flags;
+ bool do_it = false;
spin_lock_irqsave(&count_lock, flags);
count--;
@@ -361,10 +362,13 @@
cp_name_to_str(cpoint), cp_type_to_str(cptype), count);
if (count == 0) {
- lkdtm_do_action(cptype);
+ do_it = true;
count = cpoint_count;
}
spin_unlock_irqrestore(&count_lock, flags);
+
+ if (do_it)
+ lkdtm_do_action(cptype);
}
static int lkdtm_register_cpoint(enum cname which)