releases/6.12.41/i2c-virtio-avoid-hang-by-using-interruptible-completion-wait.patch

From a663b3c47ab10f66130818cf94eb59c971541c3f Mon Sep 17 00:00:00 2001
From: Viresh Kumar <viresh.kumar@linaro.org>
Date: Thu, 3 Jul 2025 17:01:02 +0530
Subject: i2c: virtio: Avoid hang by using interruptible completion wait

From: Viresh Kumar <viresh.kumar@linaro.org>

commit a663b3c47ab10f66130818cf94eb59c971541c3f upstream.

The current implementation uses wait_for_completion(), which can cause
the caller to hang indefinitely if the transfer never completes.

Switch to wait_for_completion_interruptible() so that the operation can
be interrupted by signals.

Fixes: 84e1d0bf1d71 ("i2c: virtio: disable timeout handling")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: <stable@vger.kernel.org> # v5.16+
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/b8944e9cab8eb959d888ae80add6f2a686159ba2.1751541962.git.viresh.kumar@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/i2c/busses/i2c-virtio.c |   15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

--- a/drivers/i2c/busses/i2c-virtio.c
+++ b/drivers/i2c/busses/i2c-virtio.c
@@ -116,15 +116,16 @@ static int virtio_i2c_complete_reqs(stru
 	for (i = 0; i < num; i++) {
 		struct virtio_i2c_req *req = &reqs[i];
 
-		wait_for_completion(&req->completion);
-
-		if (!failed && req->in_hdr.status != VIRTIO_I2C_MSG_OK)
-			failed = true;
+		if (!failed) {
+			if (wait_for_completion_interruptible(&req->completion))
+				failed = true;
+			else if (req->in_hdr.status != VIRTIO_I2C_MSG_OK)
+				failed = true;
+			else
+				j++;
+		}
 
 		i2c_put_dma_safe_msg_buf(reqs[i].buf, &msgs[i], !failed);
-
-		if (!failed)
-			j++;
 	}
 
 	return j;