we see the below kernel panic logs when run suspend resume test with usb mouse and usb keyboard connected. the scenario is the userspace call the hid_debug_rdesc_show to dump the input device while the device is removed. the patch hold the driver_input_lock to avoid the race. [ 5381.757295] selinux: SELinux: Could not stat /sys/devices/pci0000:00/0000:00:15.0/usb1/1-2/1-2:1.0/0003:03F0:0325.0320/input/input960/input960::scrolllock: No such file or directory. [ 5382.636498] BUG: unable to handle kernel paging request at 0000000783316040 [ 5382.651950] CPU: 1 PID: 1512 Comm: getevent Tainted: G U O 4.19.20-quilt-2e5dc0ac-00029-gc455a447dd55 #1 [ 5382.663797] RIP: 0010:hid_dump_device+0x9b/0x160 [ 5382.758853] Call Trace: [ 5382.761581] hid_debug_rdesc_show+0x72/0x1d0 [ 5382.766343] seq_read+0xe0/0x410 [ 5382.769941] full_proxy_read+0x5f/0x90 [ 5382.774121] __vfs_read+0x3a/0x170 [ 5382.788392] vfs_read+0xa0/0x150 [ 5382.791984] ksys_read+0x58/0xc0 [ 5382.801404] __x64_sys_read+0x1a/0x20 [ 5382.805483] do_syscall_64+0x55/0x110 [ 5382.809559] entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: he, bo <bo.he@xxxxxxxxx> Signed-off-by: "Zhang, Jun" <jun.zhang@xxxxxxxxx> --- drivers/hid/hid-debug.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c index ebc9ffde41e9..a353a011fbdf 100644 --- a/drivers/hid/hid-debug.c +++ b/drivers/hid/hid-debug.c @@ -1060,10 +1060,15 @@ static int hid_debug_rdesc_show(struct seq_file *f, void *p) seq_printf(f, "\n\n"); /* dump parsed data and input mappings */ + if (down_interruptible(&hdev->driver_input_lock)) + return 0; + hid_dump_device(hdev, f); seq_printf(f, "\n"); hid_dump_input_mapping(hdev, f); + up(&hdev->driver_input_lock); + return 0; } -- 2.20.1
