dc336b19e8
Do not try to queue a drd work if dr_mode is not USB_DR_MODE_OTG because the work is not inited, this may be triggered by user try to change mode file of debugfs on a single role port, which will cause below kernel dump: [ 60.115529] ------------[ cut here ]------------ [ 60.120166] WARNING: CPU: 1 PID: 627 at kernel/workqueue.c:1473 __queue_work+0x46c/0x520 [ 60.128254] Modules linked in: [ 60.131313] CPU: 1 PID: 627 Comm: sh Not tainted 5.7.0-rc4-00022-g914a586-dirty #135 [ 60.139054] Hardware name: NXP i.MX8MQ EVK (DT) [ 60.143585] pstate: a0000085 (NzCv daIf -PAN -UAO) [ 60.148376] pc : __queue_work+0x46c/0x520 [ 60.152385] lr : __queue_work+0x314/0x520 [ 60.156393] sp : ffff8000124ebc40 [ 60.159705] x29: ffff8000124ebc40 x28: ffff800011808018 [ 60.165018] x27: ffff800011819ef8 x26: ffff800011d39980 [ 60.170331] x25: ffff800011808018 x24: 0000000000000100 [ 60.175643] x23: 0000000000000013 x22: 0000000000000001 [ 60.180955] x21: ffff0000b7c08e00 x20: ffff0000b6c31080 [ 60.186267] x19: ffff0000bb99bc00 x18: 0000000000000000 [ 60.191579] x17: 0000000000000000 x16: 0000000000000000 [ 60.196891] x15: 0000000000000000 x14: 0000000000000000 [ 60.202202] x13: 0000000000000000 x12: 0000000000000000 [ 60.207515] x11: 0000000000000000 x10: 0000000000000040 [ 60.212827] x9 : ffff800011d55460 x8 : ffff800011d55458 [ 60.218138] x7 : ffff0000b7800028 x6 : 0000000000000000 [ 60.223450] x5 : ffff0000b7800000 x4 : 0000000000000000 [ 60.228762] x3 : ffff0000bb997cc0 x2 : 0000000000000001 [ 60.234074] x1 : 0000000000000000 x0 : ffff0000b6c31088 [ 60.239386] Call trace: [ 60.241834] __queue_work+0x46c/0x520 [ 60.245496] queue_work_on+0x6c/0x90 [ 60.249075] dwc3_set_mode+0x48/0x58 [ 60.252651] dwc3_mode_write+0xf8/0x150 [ 60.256489] full_proxy_write+0x5c/0xa8 [ 60.260327] __vfs_write+0x18/0x40 [ 60.263729] vfs_write+0xdc/0x1c8 [ 60.267045] ksys_write+0x68/0xf0 [ 60.270360] __arm64_sys_write+0x18/0x20 [ 60.274286] el0_svc_common.constprop.0+0x68/0x160 [ 60.279077] do_el0_svc+0x20/0x80 [ 60.282394] el0_sync_handler+0x10c/0x178 [ 60.286403] el0_sync+0x140/0x180 [ 60.289716] ---[ end trace 70b155582e2b7988 ]--- Signed-off-by: Li Jun <jun.li@nxp.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.