dma-debug: avoid spinlock recursion when disabling dma-debug
With netconsole (at least) the pr_err("... disablingn") call can
recurse back into the dma-debug code, where it'll try to grab
free_entries_lock again. Avoid the problem by doing the printk after
dropping the lock.
Link: http://lkml.kernel.org/r/1463678421-18683-1-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 4a1515f..51a76af 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -657,9 +657,9 @@
spin_lock_irqsave(&free_entries_lock, flags);
if (list_empty(&free_entries)) {
- pr_err("DMA-API: debugging out of memory - disabling\n");
global_disable = true;
spin_unlock_irqrestore(&free_entries_lock, flags);
+ pr_err("DMA-API: debugging out of memory - disabling\n");
return NULL;
}