3.5.7.17 -stable review patch. If anyone has any objections, please let me know. ------------------ From: UCHINO Satoshi <satoshi.uchino@xxxxxxxxxxxxx> commit d68c277b501889b3a50c179d1c3d704db7947b83 upstream. Without this memory barrier, the file-storage thread may fail to escape from the following while loop, because it may observe new common->thread_wakeup_needed and old bh->state which are updated by the callback functions. /* Wait for the CBW to arrive */ while (bh->state != BUF_STATE_FULL) { rc = sleep_thread(common); if (rc) return rc; } Signed-off-by: UCHINO Satoshi <satoshi.uchino@xxxxxxxxxxxxx> Acked-by: Michal Nazarewicz <mina86@xxxxxxxxxx> Signed-off-by: Felipe Balbi <balbi@xxxxxx> Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx> --- drivers/usb/gadget/f_mass_storage.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c index f67b453..277bb9b 100644 --- a/drivers/usb/gadget/f_mass_storage.c +++ b/drivers/usb/gadget/f_mass_storage.c @@ -511,6 +511,7 @@ static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep) /* Caller must hold fsg->lock */ static void wakeup_thread(struct fsg_common *common) { + smp_wmb(); /* ensure the write of bh->state is complete */ /* Tell the main thread that something has happened */ common->thread_wakeup_needed = 1; if (common->thread_task) @@ -730,6 +731,7 @@ static int sleep_thread(struct fsg_common *common) } __set_current_state(TASK_RUNNING); common->thread_wakeup_needed = 0; + smp_rmb(); /* ensure the latest bh->state is visible */ return rc; } -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html