kernel/linux.git/drivers/misc/mei/bus.c, branch linux-4.4.y

mei: bus: don't clean driver pointer

2020-07-22T07:10:06+00:00

commit e852c2c251ed9c23ae6e3efebc5ec49adb504207 upstream. It's not needed to set driver to NULL in mei_cl_device_remove() which is bus_type remove() handler as this is done anyway in __device_release_driver(). Actually this is causing an endless loop in driver_detach() on ubuntu patched kernel, while removing (rmmod) the mei_hdcp module. The reason list_empty(&drv->p->klist_devices.k_list) is always not-empty. as the check is always true in __device_release_driver() if (dev->driver != drv) return; The non upstream patch is causing this behavior, titled: 'vfio -- release device lock before userspace requests' Nevertheless the fix is correct also for the upstream. Link: https://patchwork.ozlabs.org/project/ubuntu-kernel/patch/20180912085046.3401-2-apw@canonical.com/ Cc: Cc: Andy Whitcroft Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Link: https://lore.kernel.org/r/20200628225359.2185929-1-tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman

mei: bus: prefix device names on bus with the bus name

2019-12-05T14:27:12+00:00

commit 7a2b9e6ec84588b0be65cc0ae45a65bac431496b upstream. Add parent device name to the name of devices on bus to avoid device names collisions for same client UUID available from different MEI heads. Namely this prevents sysfs collision under /sys/bus/mei/device/ In the device part leave just UUID other parameters that are required for device matching are not required here and are just bloating the name. Cc: Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Link: https://lore.kernel.org/r/20191105150514.14010-1-tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman

mei: bus: fix mei_cldev_enable KDoc

2017-01-12T10:22:47+00:00

commit 5026c9cb0744a9cd40242743ca91a5d712f468c6 upstream. Adjust function name in KDoc. Fixes: d49dc5e76fc9 (mei: bus: use mei_cldev_ prefix for the API functions) Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: fix return value on disconnection

2016-12-02T08:09:02+00:00

commit 2d4d5481e2d6f93b25fcfb13a9f20bbfbf54266a upstream. Correct errno on client disconnection is -ENODEV not -EBUSY Signed-off-by: Tomas Winkler Signed-off-by: Alexander Usyskin Signed-off-by: Greg Kroah-Hartman

mei: bus: call mei_cl_read_start under device lock

2016-06-01T19:15:50+00:00

commit bc46b45a421a64a0895dd41a34d3d2086e1ac7f6 upstream. 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. 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

2016-04-12T16:08:46+00:00

commit 15c13dfcad883a1e76b714480fb27be96247fd82 upstream. 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. Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: bus: set the device name before running fixup

2015-10-29T00:02:16+00:00

The mei bus fixup use dev_xxx services for printing to kernel log so we need to setup the device name prior to running fixup hooks. Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: bus: use correct lock ordering

2015-10-29T00:02:16+00:00

The correct lock order is cl_bus_lock device_lock me_clients_rwsem This order was violated in bus rescan and remove routines when me_client_rwsem was locked before cl_bus_lock. Chain exists of: [ 4.321653] &dev->device_lock --> &dev->me_clients_rwsem --> &dev->cl_bus_lock [ 4.321653] [ 4.321679] Possible unsafe locking scenario: [ 4.321679] [ 4.321693] CPU0 CPU1 [ 4.321701] ---- ---- [ 4.321709] lock(&dev->cl_bus_lock); [ 4.321720] lock(&dev->me_clients_rwsem); [ 4.321733] lock(&dev->cl_bus_lock); [ 4.321745] lock(&dev->device_lock); [ 4.321755] [ 4.321755] *** DEADLOCK *** [ 4.321755] Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: bus: fix c&p issue in the kdoc

2015-10-18T04:45:05+00:00

s/send/receive/ The buffer in the receive function is not used for sending Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman

mei: bus: use mei_cl_bus_ prefix consistently

2015-09-21T02:31:10+00:00

Use mei_cl_bus_ for internal bus function consistently. Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman