[PATCH v2 7/7] pipe: set FMODE_NOWAIT for named FIFOs

Askar Safin <[email protected]> Thu, 25 Jun 2026 08:34:09 +0000

Newsgroups	dev.linux.lists.fuse-devel,dev.linux.lists.patches,org.kernel.vger.linux-api,org.kernel.vger.linux-fsdevel,org.kernel.vger.linux-kernel,org.kernel.vger.netdev,org.kvack.linux-mm
Message-ID	<[email protected]>

CRIU relies on ability to do vmsplice(SPLICE_F_NONBLOCK) on named FIFOs.

Signed-off-by: Askar Safin <[email protected]>
---
 fs/pipe.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/pipe.c b/fs/pipe.c
index c0ccf21b9..a8e9b4459 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -1156,6 +1156,12 @@ static int fifo_open(struct inode *inode, struct file *filp)
 	/* We can only do regular read/write on fifos */
 	stream_open(inode, filp);
 
+	/*
+	 * CRIU relies on ability to do vmsplice(SPLICE_F_NONBLOCK)
+	 * on named FIFOs.
+	 */
+	filp->f_mode |= FMODE_NOWAIT;
+
 	switch (filp->f_mode & (FMODE_READ | FMODE_WRITE)) {
 	case FMODE_READ:
 	/*
-- 
2.47.3