BMC/Intel-BMC/linux.git/drivers/usb/core/hub.c, branch dev-4.6

usb: core: hub: hub_port_init lock controller instead of bus

2016-06-01T19:18:02+00:00

commit feb26ac31a2a5cb88d86680d9a94916a6343e9e6 upstream. The XHCI controller presents two USB buses to the system - one for USB2 and one for USB3. The hub init code (hub_port_init) is reentrant but only locks one bus per thread, leading to a race condition failure when two threads attempt to simultaneously initialise a USB2 and USB3 device: [ 8.034843] xhci_hcd 0000:00:14.0: Timeout while waiting for setup device command [ 13.183701] usb 3-3: device descriptor read/all, error -110 On a test system this failure occurred on 6% of all boots. The call traces at the point of failure are: Call Trace: [] schedule+0x37/0x90 [] usb_kill_urb+0x8d/0xd0 [] ? wake_up_atomic_t+0x30/0x30 [] usb_start_wait_urb+0xbe/0x150 [] usb_control_msg+0xbc/0xf0 [] hub_port_init+0x51e/0xb70 [] hub_event+0x817/0x1570 [] process_one_work+0x1ff/0x620 [] ? process_one_work+0x15f/0x620 [] worker_thread+0x64/0x4b0 [] ? rescuer_thread+0x390/0x390 [] kthread+0x105/0x120 [] ? kthread_create_on_node+0x200/0x200 [] ret_from_fork+0x3f/0x70 [] ? kthread_create_on_node+0x200/0x200 Call Trace: [] xhci_setup_device+0x53d/0xa40 [] xhci_address_device+0xe/0x10 [] hub_port_init+0x1bf/0xb70 [] ? trace_hardirqs_on+0xd/0x10 [] hub_event+0x817/0x1570 [] process_one_work+0x1ff/0x620 [] ? process_one_work+0x15f/0x620 [] worker_thread+0x64/0x4b0 [] ? rescuer_thread+0x390/0x390 [] kthread+0x105/0x120 [] ? kthread_create_on_node+0x200/0x200 [] ret_from_fork+0x3f/0x70 [] ? kthread_create_on_node+0x200/0x200 Which results from the two call chains: hub_port_init usb_get_device_descriptor usb_get_descriptor usb_control_msg usb_internal_control_msg usb_start_wait_urb usb_submit_urb / wait_for_completion_timeout / usb_kill_urb hub_port_init hub_set_address xhci_address_device xhci_setup_device Mathias Nyman explains the current behaviour violates the XHCI spec: hub_port_reset() will end up moving the corresponding xhci device slot to default state. As hub_port_reset() is called several times in hub_port_init() it sounds reasonable that we could end up with two threads having their xhci device slots in default state at the same time, which according to xhci 4.5.3 specs still is a big no no: "Note: Software shall not transition more than one Device Slot to the Default State at a time" So both threads fail at their next task after this. One fails to read the descriptor, and the other fails addressing the device. Fix this in hub_port_init by locking the USB controller (instead of an individual bus) to prevent simultaneous initialisation of both buses. Fixes: 638139eb95d2 ("usb: hub: allow to process more usb hub events in parallel") Link: https://lkml.org/lkml/2016/2/8/312 Link: https://lkml.org/lkml/2016/2/4/748 Signed-off-by: Chris Bainbridge Acked-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman

usb: hub: fix a typo in hub_port_init() leading to wrong logic

2016-03-04T03:44:06+00:00

A typo of j for i led to a logic bug. To rule out future confusion, the variable names are made meaningful. Signed-off-by: Oliver Neukum CC: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

Merge 4.5-rc6 into usb-next

2016-03-02T00:13:54+00:00

We want the USB fixes in here as well. Signed-off-by: Greg Kroah-Hartman

Revert "usb: hub: do not clear BOS field during reset device"

2016-02-20T22:19:34+00:00

This reverts commit d8f00cd685f5c8e0def8593e520a7fef12c22407. Tony writes: This upstream commit is causing an oops: d8f00cd685f5 ("usb: hub: do not clear BOS field during reset device") This patch has already been included in several -stable kernels. Here are the affected kernels: 4.5.0-rc4 (current git) 4.4.2 4.3.6 (currently in review) 4.1.18 3.18.27 3.14.61 How to reproduce the problem: Boot kernel with slub debugging enabled (otherwise memory corruption will cause random oopses later instead of immediately) Plug in USB 3.0 disk to xhci USB 3.0 port dd if=/dev/sdc of=/dev/null bs=65536 (where /dev/sdc is the USB 3.0 disk) Unplug USB cable while dd is still going Oops is immediate: Reported-by: Tony Battersby Cc: Du, Changbin Signed-off-by: Greg Kroah-Hartman

usb: retry reset if a device times out

2016-02-15T01:42:08+00:00

Some devices I got show an inability to operate right after power on if they are already connected. They are beyond recovery if the descriptors are requested multiple times. So in case of a timeout we rather bail early and reset again. But it must be done only on the first loop lest we get into a reset/time out spiral that can be overcome with a retry. This patch is a rework of a patch that fell through the cracks. http://www.spinics.net/lists/linux-usb/msg103263.html Signed-off-by: Oliver Neukum CC: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drivers: usb: removed assignment of 0 to static variables

2016-02-10T01:20:54+00:00

fixing the error reported by script checkpatch.pl static variables blinkenlights and old_scheme_first were initialised to 0, correcting it. Signed-off-by: Saurabh Sengar Signed-off-by: Greg Kroah-Hartman

usb: core: rename mutex usb_bus_list_lock to usb_bus_idr_lock

2016-02-07T05:55:57+00:00

Now that usb_bus_list has been removed and switched to idr rename the related mutex accordingly. Signed-off-by: Heiner Kallweit Signed-off-by: Greg Kroah-Hartman

Merge 4.5-rc2 into usb-next

2016-02-01T20:55:09+00:00

We want the USB fixes in here as well. Signed-off-by: Greg Kroah-Hartman

usb: hub: do not clear BOS field during reset device

2016-01-25T05:06:21+00:00

In function usb_reset_and_verify_device, the old BOS descriptor may still be used before allocating a new one. (usb_unlocked_disable_lpm function uses it under the situation that it fails to disable lpm.) So we cannot set the udev->bos to NULL before that, just keep what it was. It will be overwrite when allocating a new one. Crash log: BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 IP: [] usb_enable_link_state+0x2d/0x2f0 Call Trace: [] ? usb_set_lpm_timeout+0x12b/0x140 [] usb_enable_lpm+0x81/0xa0 [] usb_disable_lpm+0xa8/0xc0 [] usb_unlocked_disable_lpm+0x2c/0x50 [] usb_reset_and_verify_device+0xc3/0x710 [] ? usb_sg_wait+0x13d/0x190 [] usb_reset_device+0x133/0x280 [] usb_stor_port_reset+0x61/0x70 [] usb_stor_invoke_transport+0x88/0x520 Signed-off-by: Du, Changbin Cc: stable Signed-off-by: Greg Kroah-Hartman

USB: core, wusbcore: use bus_to_hcd

2016-01-25T05:00:33+00:00

Use bus_to_hcd() instead of open-coding it. Signed-off-by: Geliang Tang Signed-off-by: Greg Kroah-Hartman