linux/drivers/usb/gadget
Radoslav Gerganov 072684e8c5 USB: gadget: f_hid: fix deadlock in f_hidg_write()
In f_hidg_write() the write_spinlock is acquired before calling
usb_ep_queue() which causes a deadlock when dummy_hcd is being used.
This is because dummy_queue() callbacks into f_hidg_req_complete() which
tries to acquire the same spinlock. This is (part of) the backtrace when
the deadlock occurs:

  0xffffffffc06b1410 in f_hidg_req_complete
  0xffffffffc06a590a in usb_gadget_giveback_request
  0xffffffffc06cfff2 in dummy_queue
  0xffffffffc06a4b96 in usb_ep_queue
  0xffffffffc06b1eb6 in f_hidg_write
  0xffffffff8127730b in __vfs_write
  0xffffffff812774d1 in vfs_write
  0xffffffff81277725 in SYSC_write

Fix this by releasing the write_spinlock before calling usb_ep_queue()

Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: stable@vger.kernel.org # 4.11+
Fixes: 749494b6bd ("usb: gadget: f_hid: fix: Move IN request allocation to set_alt()")
Signed-off-by: Radoslav Gerganov <rgerganov@vmware.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2019-03-20 10:58:48 +02:00
..
function USB: gadget: f_hid: fix deadlock in f_hidg_write() 2019-03-20 10:58:48 +02:00
legacy USB: changes for v5.1 merge window 2019-02-15 09:08:57 +01:00
udc usb: gadget: net2272: Fix net2272_dequeue() 2019-03-20 08:50:42 +02:00
Kconfig USB: add missing SPDX lines to Kconfig and Makefiles 2019-01-22 09:08:17 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
composite.c usb: gadget: Fix OS descriptors support 2018-07-17 10:12:51 +03:00
config.c USB: gadget: Remove redundant license text 2017-11-07 15:45:02 +01:00
configfs.c usb: gadget: configfs: avoid spaces for indentation 2018-07-26 13:49:49 +03:00
configfs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
epautoconf.c usb: gadget: move non-super speed code out of usb_ep_autoconfig_ss() 2019-02-07 13:14:51 +02:00
functions.c USB: add SPDX identifiers to all remaining files in drivers/usb/ 2017-11-04 11:48:02 +01:00
u_f.c usb: gadget: Change Andrzej Pietrasiewicz's e-mail address 2019-02-11 11:12:29 +02:00
u_f.h usb: gadget: Change Andrzej Pietrasiewicz's e-mail address 2019-02-11 11:12:29 +02:00
u_os_desc.h usb: gadget: Change Andrzej Pietrasiewicz's e-mail address 2019-02-11 11:12:29 +02:00
usbstring.c usb/gadget: Constify usb_gadget_get_string "table" argument 2018-05-15 10:06:49 +03:00