From: Ville Syrjälä <[email protected]>

commit 3017cd63f26fc655d56875aaf497153ba60e9edf upstream.

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/[email protected]
Signed-off-by: Ville Syrjälä <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Willy Tarreau <[email protected]>
---
 lib/dma-debug.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index eb43517b..c32437f 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -445,9 +445,9 @@ static struct dma_debug_entry *dma_entry_alloc(void)
        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;
        }
 
-- 
2.8.0.rc2.1.gbe9624a

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