This is a note to let you know that I've just added the patch titled usb: ucsi: Add missing ppm_lock to the 6.1-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: usb-ucsi-add-missing-ppm_lock.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c9aed03a0a683fd1600ea92f2ad32232d4736272 Mon Sep 17 00:00:00 2001 From: "Christian A. Ehrhardt" <lk@xxxxxxx> Date: Sun, 21 Jan 2024 21:41:21 +0100 Subject: usb: ucsi: Add missing ppm_lock From: Christian A. Ehrhardt <lk@xxxxxxx> commit c9aed03a0a683fd1600ea92f2ad32232d4736272 upstream. Calling ->sync_write must be done while holding the PPM lock as the mailbox logic does not support concurrent commands. At least since the addition of partner task this means that ucsi_acknowledge_connector_change should be called with the PPM lock held as it calls ->sync_write. Thus protect the only call to ucsi_acknowledge_connector_change with the PPM. All other calls to ->sync_write already happen under the PPM lock. Fixes: b9aa02ca39a4 ("usb: typec: ucsi: Add polling mechanism for partner tasks like alt mode checking") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: "Christian A. Ehrhardt" <lk@xxxxxxx> Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240121204123.275441-2-lk@xxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/typec/ucsi/ucsi.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -831,7 +831,9 @@ static void ucsi_handle_connector_change clear_bit(EVENT_PENDING, &con->ucsi->flags); + mutex_lock(&ucsi->ppm_lock); ret = ucsi_acknowledge_connector_change(ucsi); + mutex_unlock(&ucsi->ppm_lock); if (ret) dev_err(ucsi->dev, "%s: ACK failed (%d)", __func__, ret); Patches currently in stable-queue which might be from lk@xxxxxxx are queue-6.1/of-unittest-fix-compile-in-the-non-dynamic-case.patch queue-6.1/usb-ucsi_acpi-fix-command-completion-handling.patch queue-6.1/usb-ucsi-add-missing-ppm_lock.patch