kernel/linux.git/drivers/misc/mei/bus.c, branch linux-4.7.y

mei: amthif: fix deadlock in initialization during a reset

2016-10-22T10:06:47+00:00

commit e728ae271f4cf71218ec06a6daf61b79466cb466 upstream. The device lock was unnecessary obtained in bus rescan work before the amthif client search. That causes incorrect lock ordering and task hang: ... [88004.613213] INFO: task kworker/1:14:21832 blocked for more than 120 seconds. ... [88004.645934] Workqueue: events mei_cl_bus_rescan_work ... The correct lock order is cl_bus_lock device_lock me_clients_rwsem Move device_lock into amthif init function that called after me_clients_rwsem is released. This fixes regression introduced by commit: commit 025fb792bac3 ("mei: split amthif client init from end of clients enumeration") Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

mei: bus: call mei_cl_read_start under device lock

2016-05-03T22:07:35+00:00

Ensure that mei_cl_read_start is called under the device lock also in the bus layer. The function updates global ctrl_wr_list which should be locked. Cc: #4.4+ Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: do not pin module if cldrv->probe() failed

2016-04-30T21:08:08+00:00

If cldrv->probe() failed in mei_cl_device_probe(), the mei module is left pinned. The patch moves __module_get(THIS_MODULE) after cldrv->probe(). Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov Signed-off-by: Greg Kroah-Hartman

mei: bus: use scnprintf in *_show

2016-03-31T23:43:05+00:00

There's no reason to duplicate the logic provided by scnprintf(). Signed-off-by: Rasmus Villemoes Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: fix double freeing of a cb during link reset

2016-02-12T03:23:28+00:00

Fix double freeing of the cb that can happen if link reset kicks in the middle of blocked write from a device on the cl bus. Free cb inside mei_cl_write function on failure and drop cb free operation from callers, during a link reset the mei_cl_write function returns with an error, but the caller doesn't know if the cb was already queued or not so it doesn't know if the cb will be freed upon queue reclaim or it has to free it itself. Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: split amthif client init from end of clients enumeration

2016-02-07T22:47:20+00:00

The amthif FW client can appear after the end of client enumeration. Amthif host client initialization is done now at FW client discovery time. Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: bus: run rescan on me_clients list change

2016-02-07T22:47:20+00:00

Since clients can be now added and removed during runtime we need to run bus rescan whenever me_clients list is modified. Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: drop reserved host client ids

2016-02-07T22:47:20+00:00

The reserved host clients can be obsoleted now, a portion of the platforms is shipped without iAMT enabled, where the reservation is not relevant and for platforms with iAMT dynamic allocation is sufficient. Dropping reserved ids makes enumeration more flexible and generic Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: bus: check if the device is enabled before data transfer

2016-02-07T22:47:20+00:00

The bus data transfer interface was missing the check if the device is in enabled state, this may lead to stack corruption during link reset. Cc: #4.0 Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: bus: fix notification event delivery

2016-02-07T22:47:20+00:00

Call wake_up cl->ev_wait only in case there is no bus client registered to the event notification. Second, since we don't have exclusive waiter wake_up_interruptible_all is not used correctly here. Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman