This is a note to let you know that I've just added the patch titled serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove() to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: serial-8250-omap-fix-unpaired-pm_runtime_put_sync-in.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 6ea361b4bd6d8951e196838671030080be0f0cc9 Author: Tony Lindgren <tony@xxxxxxxxxxx> Date: Fri Oct 28 13:58:13 2022 +0300 serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove() [ Upstream commit e3f0c638f428fd66b5871154b62706772045f91a ] On remove, we get an error for "Runtime PM usage count underflow!". I guess this driver is mostly built-in, and this issue has gone unnoticed for a while. Somehow I did not catch this issue with my earlier fix done with commit 4e0f5cc65098 ("serial: 8250_omap: Fix probe and remove for PM runtime"). Fixes: 4e0f5cc65098 ("serial: 8250_omap: Fix probe and remove for PM runtime") Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Depends-on: dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter") Link: https://lore.kernel.org/r/20221028105813.54290-1-tony@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 5707d86cac76..f3f54cb0cfca 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -1475,6 +1475,11 @@ static int omap8250_probe(struct platform_device *pdev) static int omap8250_remove(struct platform_device *pdev) { struct omap8250_priv *priv = platform_get_drvdata(pdev); + int err; + + err = pm_runtime_resume_and_get(&pdev->dev); + if (err) + return err; pm_runtime_dont_use_autosuspend(&pdev->dev); pm_runtime_put_sync(&pdev->dev);