[PATCH] fs: Add an explicit might_sleep() to iput

[KP Singh]

From: KP Singh <kpsingh@xxxxxxxxxx>

It is currently mentioned in the comments to the function that iput
might sleep when the inode is destroyed. Have it call might_sleep, as
dput already does.

Adding an explicity might_sleep() would help in quickly realizing that
iput is called from a place where sleeping is not allowed when
CONFIG_DEBUG_ATOMIC_SLEEP is enabled as noticed in the dicussion:

  https://lore.kernel.org/bpf/20200527021111.GA197666@xxxxxxxxxx/

Signed-off-by: KP Singh <kpsingh@xxxxxxxxxx>
Reviewed-by: Brendan Jackman <jackmanb@xxxxxxxxxxxx>
---
 fs/inode.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/inode.c b/fs/inode.c
index cc6e701b7e5d..f55e72e76266 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1583,6 +1583,7 @@ static void iput_final(struct inode *inode)
  */
 void iput(struct inode *inode)
 {
+	might_sleep();
 	if (!inode)
 		return;
 	BUG_ON(inode->i_state & I_CLEAR);
-- 
2.27.0.rc0.183.gde8f92d652-goog