7f9745ab34
commit 4bf584a03eec674975ee9fe36c8583d9d470dab1 upstream.
When do system reboot, it calls dwc3_shutdown and the whole debugfs
for dwc3 has removed first, when the gadget tries to do deinit, and
remove debugfs for its endpoints, it meets NULL pointer dereference
issue when call debugfs_lookup. Fix it by removing the whole dwc3
debugfs later than dwc3_drd_exit.
[ 2924.958838] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000002
....
[ 2925.030994] pstate: 60000005 (nZCv daif -PAN -UAO -TCO BTYPE=--)
[ 2925.037005] pc : inode_permission+0x2c/0x198
[ 2925.041281] lr : lookup_one_len_common+0xb0/0xf8
[ 2925.045903] sp : ffff80001276ba70
[ 2925.049218] x29: ffff80001276ba70 x28: ffff0000c01f0000 x27: 0000000000000000
[ 2925.056364] x26: ffff800011791e70 x25: 0000000000000008 x24: dead000000000100
[ 2925.063510] x23: dead000000000122 x22: 0000000000000000 x21: 0000000000000001
[ 2925.070652] x20: ffff8000122c6188 x19: 0000000000000000 x18: 0000000000000000
[ 2925.077797] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000004
[ 2925.084943] x14: ffffffffffffffff x13: 0000000000000000 x12: 0000000000000030
[ 2925.092087] x11: 0101010101010101 x10: 7f7f7f7f7f7f7f7f x9 : ffff8000102b2420
[ 2925.099232] x8 : 7f7f7f7f7f7f7f7f x7 : feff73746e2f6f64 x6 : 0000000000008080
[ 2925.106378] x5 : 61c8864680b583eb x4 : 209e6ec2d263dbb7 x3 : 000074756f307065
[ 2925.113523] x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffff8000122c6188
[ 2925.120671] Call trace:
[ 2925.123119] inode_permission+0x2c/0x198
[ 2925.127042] lookup_one_len_common+0xb0/0xf8
[ 2925.131315] lookup_one_len_unlocked+0x34/0xb0
[ 2925.135764] lookup_positive_unlocked+0x14/0x50
[ 2925.140296] debugfs_lookup+0x68/0xa0
[ 2925.143964] dwc3_gadget_free_endpoints+0x84/0xb0
[ 2925.148675] dwc3_gadget_exit+0x28/0x78
[ 2925.152518] dwc3_drd_exit+0x100/0x1f8
[ 2925.156267] dwc3_remove+0x11c/0x120
[ 2925.159851] dwc3_shutdown+0x14/0x20
[ 2925.163432] platform_shutdown+0x28/0x38
[ 2925.167360] device_shutdown+0x15c/0x378
[ 2925.171291] kernel_restart_prepare+0x3c/0x48
[ 2925.175650] kernel_restart+0x1c/0x68
[ 2925.179316] __do_sys_reboot+0x218/0x240
[ 2925.183247] __arm64_sys_reboot+0x28/0x30
[ 2925.187262] invoke_syscall+0x48/0x100
[ 2925.191017] el0_svc_common.constprop.0+0x48/0xc8
[ 2925.195726] do_el0_svc+0x28/0x88
[ 2925.199045] el0_svc+0x20/0x30
[ 2925.202104] el0_sync_handler+0xa8/0xb0
[ 2925.205942] el0_sync+0x148/0x180
[ 2925.209270] Code: a9025bf5 2a0203f5 121f0056 370802b5 (79400660)
[ 2925.215372] ---[ end trace 124254d8e485a58b ]---
[ 2925.220012] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
[ 2925.227676] Kernel Offset: disabled
[ 2925.231164] CPU features: 0x00001001,20000846
[ 2925.235521] Memory Limit: none
[ 2925.238580] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---
Fixes: 8d396bb0a5b6 ("usb: dwc3: debugfs: Add and remove endpoint dirs dynamically")
Cc: Jack Pham <jackp@codeaurora.org>
Tested-by: Jack Pham <jackp@codeaurora.org>
Signed-off-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20210608105656.10795-1-peter.chen@kernel.org
(cherry picked from commit 2a042767814bd0edf2619f06fecd374e266ea068)
Link: https://lore.kernel.org/r/20210615080847.GA10432@jackp-linux.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To understand all the Linux-USB framework, you'll use these resources:
* This source code. This is necessarily an evolving work, and
includes kerneldoc that should help you get a current overview.
("make pdfdocs", and then look at "usb.pdf" for host side and
"gadget.pdf" for peripheral side.) Also, Documentation/usb has
more information.
* The USB 2.0 specification (from www.usb.org), with supplements
such as those for USB OTG and the various device classes.
The USB specification has a good overview chapter, and USB
peripherals conform to the widely known "Chapter 9".
* Chip specifications for USB controllers. Examples include
host controllers (on PCs, servers, and more); peripheral
controllers (in devices with Linux firmware, like printers or
cell phones); and hard-wired peripherals like Ethernet adapters.
* Specifications for other protocols implemented by USB peripheral
functions. Some are vendor-specific; others are vendor-neutral
but just standardized outside of the www.usb.org team.
Here is a list of what each subdirectory here is, and what is contained in
them.
core/ - This is for the core USB host code, including the
usbfs files and the hub class driver ("hub_wq").
host/ - This is for USB host controller drivers. This
includes UHCI, OHCI, EHCI, and others that might
be used with more specialized "embedded" systems.
gadget/ - This is for USB peripheral controller drivers and
the various gadget drivers which talk to them.
Individual USB driver directories. A new driver should be added to the
first subdirectory in the list below that it fits into.
image/ - This is for still image drivers, like scanners or
digital cameras.
../input/ - This is for any driver that uses the input subsystem,
like keyboard, mice, touchscreens, tablets, etc.
../media/ - This is for multimedia drivers, like video cameras,
radios, and any other drivers that talk to the v4l
subsystem.
../net/ - This is for network drivers.
serial/ - This is for USB to serial drivers.
storage/ - This is for USB mass-storage drivers.
class/ - This is for all USB device drivers that do not fit
into any of the above categories, and work for a range
of USB Class specified devices.
misc/ - This is for all USB device drivers that do not fit
into any of the above categories.