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* xhci: Add bus number to some debug messagesMathias Nyman2021-08-261-1/+2
| | | | | | | | | | As we register two usb buses for each xHC, and systems with several hosts are more and more common it is getting hard to follow the flow of debug messages without knowing which bus they belong to Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210820123503.2605901-7-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: Add additional dynamic debug to follow URBs in cancel and error cases.Mathias Nyman2021-08-261-6/+24
| | | | | | | | | | | Add more debugging messages to follow what happends to a URB internally in special cases like URB cancel, halted endpoints and endpoint reset. Helps tracking issues like URB never given back by host. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210820123503.2605901-6-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: Fix failure to give back some cached cancelled URBs.Mathias Nyman2021-08-261-15/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Only TDs with status TD_CLEARING_CACHE will be given back after cache is cleared with a set TR deq command. xhci_invalidate_cached_td() failed to set the TD_CLEARING_CACHE status for some cancelled TDs as it assumed an endpoint only needs to clear the TD it stopped on. This isn't always true. For example with streams enabled an endpoint may have several stream rings, each stopping on a different TDs. Note that if an endpoint has several stream rings, the current code will still only clear the cache of the stream pointed to by the last cancelled TD in the cancel list. This patch only focus on making sure all canceled TDs are given back, avoiding hung task after device removal. Another fix to solve clearing the caches of all stream rings with cancelled TDs is needed, but not as urgent. This issue was simultanously discovered and debugged by by Tao Wang, with a slightly different fix proposal. Fixes: 674f8438c121 ("xhci: split handling halted endpoints into two steps") Cc: <stable@vger.kernel.org> #5.12 Reported-by: Tao Wang <wat@codeaurora.org> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210820123503.2605901-4-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: fix even more unsafe memory usage in xhci tracingMathias Nyman2021-08-261-1/+2
| | | | | | | | | | | | | | | | | | | | Removes static char buffer usage in the following decode functions: xhci_decode_ctrl_ctx() xhci_decode_slot_context() xhci_decode_usbsts() xhci_decode_doorbell() xhci_decode_ep_context() Caller must provide a buffer to use. In tracing use __get_str() as recommended to pass buffer. Minor changes are needed in other xhci code as these functions are also used elsewhere Cc: <stable@vger.kernel.org> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210820123503.2605901-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: Add adaptive interrupt rate for isoch TRBs with XHCI_AVOID_BEI quirkMathias Nyman2021-06-171-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | Save a bit of power by not interrupting so often by default if XHCI_AVOID_BEI quirk is set. In normal cases the xhci driver will only generate an interrupt on the last isochronous TRB of an URB. In a common UVC webcam usecase there are 32 TRBs per URB. if AVOID_BEI flag is set then xhci driver will force an interrupt every 8th isoc TRB to make sure the event ring doesn't get too full. This is however way too frequent in common single webcam use cases, causing 1000 interrupts/sec and thus poor powermanagement performance. Instead start with interrupting every 32 isoc TRB, and halve it in case event ring becomes half-full. Stop halving when reaching a rate of every 8th trb. This is a one way solution. If interrupt rate is increased it will stay high until driver is reloaded. The highest rate is the same as the old default rate. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210617150354.1512157-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: Fix 5.12 regression of missing xHC cache clearing command after a StallMathias Nyman2021-05-251-2/+6
| | | | | | | | | | | | | | | | | | | | If endpoints halts due to a stall then the dequeue pointer read from hardware may already be set ahead of the stalled TRB. After commit 674f8438c121 ("xhci: split handling halted endpoints into two steps") in 5.12 xhci driver won't issue a Set TR Dequeue if hardware dequeue pointer is already in the right place. Turns out the "Set TR Dequeue pointer" command is anyway needed as it in addition to moving the dequeue pointer also clears endpoint state and cache. Fixes: 674f8438c121 ("xhci: split handling halted endpoints into two steps") Cc: <stable@vger.kernel.org> # 5.12 Reported-by: Peter Ganzhorn <peter.ganzhorn@googlemail.com> Tested-by: Peter Ganzhorn <peter.ganzhorn@googlemail.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210525074100.1154090-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: fix giving back URB with incorrect status regression in 5.12Mathias Nyman2021-05-251-5/+1
| | | | | | | | | | | | | | | | | | 5.12 kernel changes how xhci handles cancelled URBs and halted endpoints. Among these changes cancelled and stalled URBs are no longer given back before they are cleared from xHC hardware cache. These changes unfortunately cleared the -EPIPE status of a stalled transfer in one case before giving bak the URB, causing a USB card reader to fail from working. Fixes: 674f8438c121 ("xhci: split handling halted endpoints into two steps") Cc: <stable@vger.kernel.org> # 5.12 Reported-by: Peter Ganzhorn <peter.ganzhorn@googlemail.com> Tested-by: Peter Ganzhorn <peter.ganzhorn@googlemail.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210525074100.1154090-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: Fix giving back cancelled URBs even if halted endpoint can't resetMathias Nyman2021-05-131-5/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 9ebf30007858 ("xhci: Fix halted endpoint at stop endpoint command completion") in 5.12 changes how cancelled URBs are given back. To cancel a URB xhci driver needs to stop the endpoint first. To clear a halted endpoint xhci driver needs to reset the endpoint. In rare cases when an endpoint halt (error) races with a endpoint stop we need to clear the reset before removing, and giving back the cancelled URB. The above change in 5.12 takes care of this, but it also relies on the reset endpoint completion handler to give back the cancelled URBs. There are cases when driver refuses to queue reset endpoint commands, for example when a link suddenly goes to an inactive error state. In this case the cancelled URB is never given back. Fix this by giving back the URB in the stop endpoint if queuing a reset endpoint command fails. Fixes: 9ebf30007858 ("xhci: Fix halted endpoint at stop endpoint command completion") CC: <stable@vger.kernel.org> # 5.12 Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210512080816.866037-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: prevent double-fetch of transfer and transfer event TRBsMathias Nyman2021-04-061-23/+19
| | | | | | | | | | | | | | | | The same values are parsed several times from transfer and event TRBs by different functions in the same call path, all while processing one transfer event. As the TRBs are in DMA memory and can be accessed by the xHC host we want to avoid this to prevent double-fetch issues. To resolve this pass the already parsed values to the different functions in the path of parsing a transfer event Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210406070208.3406266-5-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* USB: xhci: drop workaround for forced irq threadingJohan Hovold2021-03-231-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | Force-threaded interrupt handlers used to run with interrupts enabled, something which could lead to deadlocks in case a threaded handler shared a lock with code running in hard interrupt context (e.g. timer callbacks) and did not explicitly disable interrupts. Since commit 81e2073c175b ("genirq: Disable interrupts for force threaded handlers") interrupt handlers always run with interrupts disabled on non-RT so that drivers no longer need to do handle forced threading ("threadirqs"). Drop the now obsolete workaround added by commit 63aea0dbab90 ("USB: xhci: fix lock-inversion problem"). Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210322111140.32056-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge 5.12-rc3 into usb-nextGreg Kroah-Hartman2021-03-151-1/+2
|\ | | | | | | | | | | We want the USB fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * usb: xhci: do not perform Soft Retry for some xHCI hostsStanislaw Gruszka2021-03-111-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On some systems rt2800usb and mt7601u devices are unable to operate since commit f8f80be501aa ("xhci: Use soft retry to recover faster from transaction errors") Seems that some xHCI controllers can not perform Soft Retry correctly, affecting those devices. To avoid the problem add xhci->quirks flag that restore pre soft retry xhci behaviour for affected xHCI controllers. Currently those are AMD_PROMONTORYA_4 and AMD_PROMONTORYA_2, since it was confirmed by the users: on those xHCI hosts issue happen and is gone after disabling Soft Retry. [minor commit message rewording for checkpatch -Mathias] Fixes: f8f80be501aa ("xhci: Use soft retry to recover faster from transaction errors") Cc: <stable@vger.kernel.org> # 4.20+ Reported-by: Bernhard <bernhard.gebetsberger@gmx.at> Tested-by: Bernhard <bernhard.gebetsberger@gmx.at> Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202541 Link: https://lore.kernel.org/r/20210311115353.2137560-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | usb: xhci-mtk: support to build xhci-mtk-hcd.koChunfeng Yun2021-03-101-1/+0
|/ | | | | | | | | | | | | Currently xhci-hcd.ko building depends on USB_XHCI_MTK, this is not flexible for some cases. For example: USB_XHCI_HCD is y, and USB_XHCI_MTK is m, then we can't implement extended functions if only update xhci-mtk.ko This patch is used to remove the dependence. Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com> Link: https://lore.kernel.org/r/0b62e21ddfacc1c2874726dd27ccab80c993f303.1615170625.git.chunfeng.yun@mediatek.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge 5.11-rc7 into usb-nextGreg Kroah-Hartman2021-02-081-11/+20
|\ | | | | | | | | | | We need the USB fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * xhci: fix bounce buffer usage for non-sg list caseMathias Nyman2021-02-031-11/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xhci driver may in some special cases need to copy small amounts of payload data to a bounce buffer in order to meet the boundary and alignment restrictions set by the xHCI specification. In the majority of these cases the data is in a sg list, and driver incorrectly assumed data is always in urb->sg when using the bounce buffer. If data instead is contiguous, and in urb->transfer_buffer, we may still need to bounce buffer a small part if data starts very close (less than packet size) to a 64k boundary. Check if sg list is used before copying data to/from it. Fixes: f9c589e142d0 ("xhci: TD-fragment, align the unsplittable case with a bounce buffer") Cc: stable@vger.kernel.org Reported-by: Andreas Hartmann <andihartmann@01019freenet.de> Tested-by: Andreas Hartmann <andihartmann@01019freenet.de> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210203113702.436762-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: handle halting transfer event properly after endpoint stop and halt raced.Mathias Nyman2021-01-291-16/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we receive a transfer event indicating that an endpoint should be halted, but current endpoint state doesn't match it, then the halt might be just resolved by the stop endpoint completion handler that detects the halted endpoint due to a context state error. In this case the TD we halted on is already moved to the cancelled TD list, and should not be successfully completed and given back anymore. Let the stop endpoint completion handler reset the endpoint, and then let the reset endpoint handler give back the cancelled TD among all other ones on the cancelled TD list Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-28-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: Check for pending reset endpoint command before queueing a new one.Mathias Nyman2021-01-291-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | A halted endpoint can be detected both when transfer events complete, and in stop endpoint command completion. Both these handlers will start clearing up the halted endpoint and queue a reset endpoint command. It's possible to get both events for the same halted endpoint if right after a URB cancel queues a stop endpoint command the endpoint stalls. Use the EP_HALTED flag to prevent resetting the endpoint twice. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-27-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: remove obsolete dequeue pointer moving codeMathias Nyman2021-01-291-182/+0
| | | | | | | | | | | | | | | | | | | | | | xhci_find_new_dequeue_state() and xhci_queue_new_dequeue_state() are no longer used afer introducing the move_dequeue_past_td() function. also remove struct xhci_dequeue_state as its no longer used. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-26-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: introduce a new move_dequeue_past_td() function to replace old code.Mathias Nyman2021-01-291-7/+145
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace xhci_find_new_dequeue_state() and xhci_queue_new_dequeue_state() functions with one combined function. These function were always called after each other, and had a lot of extra code just to pass the newly found dequeue state from the first function to the other. The new function also returns error in case there is a failure to queue the new dequeue state. This way the caller can decide on recovery measures to handle it. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-25-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: handle stop endpoint command completion with endpoint in running state.Mathias Nyman2021-01-291-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Handle race where a stop endpoint command fails with "context state error" as hardware hasn't actually started the ring yet after a previous urb cancellation completed and restarted the endpoint. Flushing the doorbell write that restart the endpoint reduced these cases, but didn't completely resolve them. Check if the ring is running in the stop endpoint completion handler, and issue a new stop endpoint command in this case. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-24-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: Fix halted endpoint at stop endpoint command completionMathias Nyman2021-01-291-2/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xhci 4.6.9: "A busy endpoint may asynchronously transition from the Running to the Halted or Error state due to error conditions detected while processing TRBs. A possible race condition may occur if software, thinking an endpoint is in the running state, issues a Stop Endpoint Command, however at the same time the xHC asynchronously transitions the endpoint to the Halted or Error state. In this case, a Context State Error may be generated for the command completion. Software may verify that this case occurred by inspecting the EP State for Halted or Error when a Stop Endpoint Command results in a Context State Error." Halted endpoints were not detected or handled at all in the stop endpoint completion handler. A set TR Deq ptr command was bluntly queued instead of resetting the endpoint first. The set TR Deq command would fail with a context state error. Fix this case by resetting the halted endpoint first to get it to a stopped state instead of the halted (error) state. Handle cancelled TDs once endpoint reset completes, invalidating cancelled TDs on ring either by turning them to no-op, or in case ring stopped on cancelled TD then move hardware dequeue pointer past it, which will clear the cancelled TD from hw cache, and make sure HW does not process it Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-23-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: split handling halted endpoints into two stepsMathias Nyman2021-01-291-91/+87
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't queue both a reset endpoint command and a set TR deq command at once when handling a halted endpoint. split this into two steps. Initially only queue a reset endpoint command, and then if needed queue a set TR deq command in the reset endpoint handler. Note: This removes the RESET_EP_QUIRK handling which was added in commit ac9d8fe7c6a8 ("USB: xhci: Add quirk for Fresco Logic xHCI hardware.") This quirk was added in 2009 for prototype xHCI hardware meant for evaluation purposes only, and should not reach consumers. This hardware could not handle two commands queued at once, and had bad data in the output context after a reset endpoint command. After this patch two command are no longer queued at once, so that part is solved in this rewrite, but the workaround for bad data in the output context solved by issuing an extra configure endpoint command is bluntly removed. Adding this workaround to the new rewrite just adds complexity, and I think it's time to let this quirk go. Print a debug message instead. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-22-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: move and rename xhci_cleanup_halted_endpoint()Mathias Nyman2021-01-291-41/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Halted endpoints can be discoverd both when handling transfer events and command completion events. Move code that handles halted endpoints before both of those event handlers. Rename the function to xhci_handle_halted_ep() to better describe what it does. Try to reserve "cleanup" word in function names for last stage cleanup activities. No functional changes Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-21-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: turn cancelled td cleanup to its own functionMathias Nyman2021-01-291-55/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Refactor handler for stop endpoint command completion. Yank out the part that invalidates cancelled TDs and turn it into a separate function. Invalidating cancelled TDs should be done while the ring is stopped, but not exclusively in the stop endpoint command completeion handler. We will need to invalidate TDs after resetting endpoints as well. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-20-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: store TD status in the td struct instead of passing it alongMathias Nyman2021-01-291-27/+29
| | | | | | | | | | | | | | | | | | In cases where the TD can't be given back in current handler we want to be able to store it until its time to return the TD. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-19-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: use xhci_td_cleanup() helper when giving back cancelled URBsMathias Nyman2021-01-291-7/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | use the existing xhci_td_cleanup() to give back cancelled TDs when a ring is stopped. A minor change to make sure we don't try to remove an already removed td from the list is needed as cancelled TDs are already removed from the td_list immediatelty when it's cancelled. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-18-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: move xhci_td_cleanup so it can be called by more functionsMathias Nyman2021-01-291-46/+46
| | | | | | | | | | | | | | | | No funtional changes Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-17-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: Add xhci_reset_halted_ep() helper functionMathias Nyman2021-01-291-6/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Create a separate helper function to issue reset endpont commands to clear halted endpoints. This is useful for cases where a halted endpoint is discovered while completing another command, and the endpoint halt needs to be cleared with a endpoint reset first. No functional changes Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-16-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: flush endpoint start to reduce race risk with stop endpoint command.Mathias Nyman2021-01-291-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Stop endpoint command fails with "context state error" if the endpoint is already stopped. This case was observed when a previous URB cancel had just completed and rang the doorbell to restart the ring, when a new URB cancel queued a stop endpoint command. >From xHC hardware pov the endpoint had not yet started, so the stop endpoint command failed with context state error. Right after this the doorbell ring took effect and ring was restarted. Interrupt handler saw a stop endpoint command completion event with "context state error" and discovered that the ring was back up in running state. flushing the write reduces these cases in stress testing, but does not completely remove the issue. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-15-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: Check link TRBs when updating ring enqueue and dequeue pointers.Mathias Nyman2021-01-291-5/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xhci driver relies on link TRBs existing in the correct places in TRB ring buffers shared with the host controller. The controller should not modify these link TRBs, but in theory a faulty xHC could do it. Add some basic sanity checks to avoid infinite loops in interrupt handler, or accessing unallocated memory outside a ring segment due to missing or misplaced link TRBs. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-14-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: avoid DMA double fetch when reading event trb type.Mathias Nyman2021-01-291-15/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of re-reading, masking and endianness correcting the same trb several times to get the trb type from an event, just do it once and store it in a local variable. Also pass the trb_type directly to the vendor specific event handler, avoiding one more similar read. In addition to the security benefit this also cleans up the code and helps readability. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-13-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: remove extra loop in interrupt contextMathias Nyman2021-01-291-7/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When finishing a TD we walk the endpoint dequeue trb pointer until it matches the last TRB of the TD. TDs can contain over 100 TRBs, meaning we call a function 100 times, do a few comparisons and increase a couple values for each of these calls, all in interrupt context. This can all be avoided by adding a pointer to the last TRB segment, and a number of TRBs in the TD. So instead of walking through each TRB just set the new dequeue segment, pointer, and number of free TRBs directly. Getting rid of the while loop also reduces the risk of getting stuck in a infinite loop in the interrupt handler. Loop relied on valid matching dequeue and last_trb values to break. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-12-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: check slot_id is valid before gathering slot infoLalithambika Krishna Kumar2021-01-291-1/+6
| | | | | | | | | | | | | | | | | | | | | | Check that the slot_id that we dug out from command completion event TRB, is valid before using it to identify the slot associated with the command that generated the event. Signed-off-by: Lalithambika Krishna Kumar <lalithambika.krishnakumar@intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-11-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: prevent a theoretical endless loop while preparing rings.Mathias Nyman2021-01-291-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xhci driver links together segments in a ring buffer by turning the last TRB of a segment into a link TRB, pointing to the beginning of the next segment. If the first TRB of every segment for some unknown reason is a link TRB pointing to the next segment, then prepare_ring() loops indefinitely. This isn't something the xhci driver would do. xHC hardware has access to these rings, it sholdn't be writing link TRBs either, but with broken xHC hardware this could in theory be possible. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-10-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: remove xhci_stream_id_to_ring() helperMathias Nyman2021-01-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | The one case that used this function can use the xhci_triad_to_transfer_ring() helper instead. Avoid having several functions doing basically the same thing. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-9-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: add xhci_virt_ep_to_ring() helperMathias Nyman2021-01-291-24/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Two existing ring helpers, xhci_triad_to_transfer_ring() and xhci_stream_id_to_ring() have partially similar functionality. Both have some limitation, especieally with boundary checking. Add a new xhci_virt_ep_to_ring() helper with proper boundary checking that can replace parts of one helper, and later will completely replace the other helper. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-8-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: check virt_dev is valid before dereferencing itMathias Nyman2021-01-291-3/+9
| | | | | | | | | | | | | | | | | | | | Check that the xhci_virt_dev structure that we dug out based on a slot_id value from a command completion is valid before dereferencing it. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-7-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: add xhci_get_virt_ep() helperMathias Nyman2021-01-291-24/+50
| | | | | | | | | | | | | | | | | | | | | | In several event handlers we need to find the right endpoint structure from slot_id and ep_index in the event. Add a helper for this, check that slot_id and ep_index are valid. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-6-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: remove unused event parameter from completion handlersMathias Nyman2021-01-291-8/+6
| | | | | | | | | | | | | | | | | | | | several command completion handlers are passed the event trb as a paramtere even if it't not used. Remove it. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-5-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: adjust parameters passed to cleanup_halted_endpoint()Mathias Nyman2021-01-291-21/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of passing slot id and endpoint index to cleanup_halted_endpoint() pass the endpoint structure pointer as it's already known. Avoids again digging out the endpoint structure based on slot id and endpoint index, and passing them along the call chain for this purpose only. Add slot_id to the virt_dev structure so that it can easily be found from a virt_dev, or its child, the virt_ep endpoint structure. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-4-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: get isochronous ring directly from endpoint structureMathias Nyman2021-01-291-11/+6
| | | | | | | | | | | | | | | | | | | | | | | | isochronous endpoints do not support streams, meaning that there is only one ring per endpoint. Avoid double-fetching the transfer event DMA to get the ring. Also makes passing the event to skip_isoc_td() uncecessary. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | xhci: Avoid parsing transfer events several timesMathias Nyman2021-01-291-20/+8
|/ | | | | | | | | | | | | | | | | When handling transfer events the event is passed along the handling callpath and parsed again in several occasions. The event contains slot_id and endpoint index, from which the driver endpoint structure can be found. There wasn't however a way to get the endpoint index or parent usb device from this endpoint structure. A lot of extra event parsing, and thus some DMA doublefetch cases, and excess variables and code can be avoided by adding endpoint index and parent usb virt device pointer to the endpoint structure. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210129130044.206855-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: make sure TRB is fully written before giving it to the controllerMathias Nyman2021-01-151-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Once the command ring doorbell is rung the xHC controller will parse all command TRBs on the command ring that have the cycle bit set properly. If the driver just started writing the next command TRB to the ring when hardware finished the previous TRB, then HW might fetch an incomplete TRB as long as its cycle bit set correctly. A command TRB is 16 bytes (128 bits) long. Driver writes the command TRB in four 32 bit chunks, with the chunk containing the cycle bit last. This does however not guarantee that chunks actually get written in that order. This was detected in stress testing when canceling URBs with several connected USB devices. Two consecutive "Set TR Dequeue pointer" commands got queued right after each other, and the second one was only partially written when the controller parsed it, causing the dequeue pointer to be set to bogus values. This was seen as error messages: "Mismatch between completed Set TR Deq Ptr command & xHCI internal state" Solution is to add a write memory barrier before writing the cycle bit. Cc: <stable@vger.kernel.org> Tested-by: Ross Zwisler <zwisler@google.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210115161907.2875631-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* usb: xhci: Use temporary buffer to consolidate SGTejas Joglekar2020-12-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Synopsys xHC has an internal TRB cache of size TRB_CACHE_SIZE for each endpoint. The default value for TRB_CACHE_SIZE is 16 for SS and 8 for HS. The controller loads and updates the TRB cache from the transfer ring in system memory whenever the driver issues a start transfer or update transfer command. For chained TRBs, the Synopsys xHC requires that the total amount of bytes for all TRBs loaded in the TRB cache be greater than or equal to 1 MPS. Or the chain ends within the TRB cache (with a last TRB). If this requirement is not met, the controller will not be able to send or receive a packet and it will hang causing a driver timeout and error. This can be a problem if a class driver queues SG requests with many small-buffer entries. The XHCI driver will create a chained TRB for each entry which may trigger this issue. This patch adds logic to the XHCI driver to detect and prevent this from happening. For every (TRB_CACHE_SIZE - 2), we check the total buffer size of the SG list and if the last window of (TRB_CACHE_SIZE - 2) SG list length and we don't make up at least 1 MPS, we create a temporary buffer to consolidate full SG list into the buffer. We check at (TRB_CACHE_SIZE - 2) window because it is possible that there would be a link and/or event data TRB that take up to 2 of the cache entries. We discovered this issue with devices on other platforms but have not yet come across any device that triggers this on Linux. But it could be a real problem now or in the future. All it takes is N number of small chained TRBs. And other instances of the Synopsys IP may have smaller values for the TRB_CACHE_SIZE which would exacerbate the problem. Signed-off-by: Tejas Joglekar <joglekar@synopsys.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20201208092912.1773650-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* usb: fix a few cases of -WfallthroughNick Desaulniers2020-11-131-0/+2
| | | | | | | | | | | The "fallthrough" pseudo-keyword was added as a portable way to denote intentional fallthrough. Clang will still warn on cases where there is a fallthrough to an immediate break. Add explicit breaks for those cases. Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20201111014716.260633-1-ndesaulniers@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: Tune interrupt blocking for isochronous transfersMathias Nyman2020-09-201-4/+19
| | | | | | | | | | | | | | | | | | | | | | | | | controllers with XHCI_AVOID_BEI quirk cause too frequent interrupts and affect power management. To avoid interrupting on every isochronous interval the BEI (Block Event Interrupt) flag is set for all except the last Isoch TRB in a URB. This lead to event ring filling up in case several isoc URB were queued and cancelled rapidly, which some controllers didn't handle well, and thus the XHCI_AVOID_BEI quirk was introduced. see commit 227a4fd801c8 ("usb: xhci: apply XHCI_AVOID_BEI quirk to all Intel xHCI controllers") With the XHCI_AVOID_BEI quirk each Isoch TRB will trigger an interrupt. This can cause up to 8000 interrupts per second for isochronous transfers with HD USB3 cameras, affecting power saving. The event ring fits 256 events, instead of interrupting on every isochronous TRB if XHCI_AVOID_BEI is set we make sure at least every 8th Isochronous TRB asserts an interrupt, clearing the event ring. Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20200918131752.16488-9-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva2020-08-241-1/+1
| | | | | | | | | | Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
* usb: xhci: Fix NULL pointer dereference when enqueuing trbs from urb sg listSriharsha Allenki2020-05-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On platforms with IOMMU enabled, multiple SGs can be coalesced into one by the IOMMU driver. In that case the SG list processing as part of the completion of a urb on a bulk endpoint can result into a NULL pointer dereference with the below stack dump. <6> Unable to handle kernel NULL pointer dereference at virtual address 0000000c <6> pgd = c0004000 <6> [0000000c] *pgd=00000000 <6> Internal error: Oops: 5 [#1] PREEMPT SMP ARM <2> PC is at xhci_queue_bulk_tx+0x454/0x80c <2> LR is at xhci_queue_bulk_tx+0x44c/0x80c <2> pc : [<c08907c4>] lr : [<c08907bc>] psr: 000000d3 <2> sp : ca337c80 ip : 00000000 fp : ffffffff <2> r10: 00000000 r9 : 50037000 r8 : 00004000 <2> r7 : 00000000 r6 : 00004000 r5 : 00000000 r4 : 00000000 <2> r3 : 00000000 r2 : 00000082 r1 : c2c1a200 r0 : 00000000 <2> Flags: nzcv IRQs off FIQs off Mode SVC_32 ISA ARM Segment none <2> Control: 10c0383d Table: b412c06a DAC: 00000051 <6> Process usb-storage (pid: 5961, stack limit = 0xca336210) <snip> <2> [<c08907c4>] (xhci_queue_bulk_tx) <2> [<c0881b3c>] (xhci_urb_enqueue) <2> [<c0831068>] (usb_hcd_submit_urb) <2> [<c08350b4>] (usb_sg_wait) <2> [<c089f384>] (usb_stor_bulk_transfer_sglist) <2> [<c089f2c0>] (usb_stor_bulk_srb) <2> [<c089fe38>] (usb_stor_Bulk_transport) <2> [<c089f468>] (usb_stor_invoke_transport) <2> [<c08a11b4>] (usb_stor_control_thread) <2> [<c014a534>] (kthread) The above NULL pointer dereference is the result of block_len and the sent_len set to zero after the first SG of the list when IOMMU driver is enabled. Because of this the loop of processing the SGs has run more than num_sgs which resulted in a sg_next on the last SG of the list which has SG_END set. Fix this by check for the sg before any attributes of the sg are accessed. [modified reason for null pointer dereference in commit message subject -Mathias] Fixes: f9c589e142d04 ("xhci: TD-fragment, align the unsplittable case with a bounce buffer") Cc: stable@vger.kernel.org Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20200514110432.25564-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: Don't clear hub TT buffer on ep0 protocol stallMathias Nyman2020-04-211-5/+11
| | | | | | | | | | | | | | | | | | | | | | | | The default control endpoint ep0 can return a STALL indicating the device does not support the control transfer requests. This is called a protocol stall and does not halt the endpoint. xHC behaves a bit different. Its internal endpoint state will always be halted on any stall, even if the device side of the endpiont is not halted. So we do need to issue the reset endpoint command to clear the xHC host intenal endpoint halt state, but should not request the HS hub to clear the TT buffer unless device side of endpoint is halted. Clearing the hub TT buffer at protocol stall caused ep0 to become unresponsive for some FS/LS devices behind HS hubs, and class drivers failed to set the interface due to timeout: usb 1-2.1: 1:1: usb_set_interface failed (-110) Fixes: ef513be0a905 ("usb: xhci: Add Clear_TT_Buffer") Cc: <stable@vger.kernel.org> # v5.3 Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20200421140822.28233-4-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xhci: Fix handling halted endpoint even if endpoint ring appears emptyMathias Nyman2020-04-211-1/+29
| | | | | | | | | | | | | | | | | | | | | | | If a class driver cancels its only URB then the endpoint ring buffer will appear empty to the xhci driver. xHC hardware may still process cached TRBs, and complete with a STALL, halting the endpoint. This halted endpoint was not handled correctly by xhci driver as events on empty rings were all assumed to be spurious events. xhci driver refused to restart the ring with EP_HALTED flag set, so class driver was never informed the endpoint halted even if it queued new URBs. The host side of the endpoint needs to be reset, and dequeue pointer should be moved in order to clear the cached TRBs and resetart the endpoint. Small adjustments in finding the new dequeue pointer are needed to support the case of stall on an empty ring and unknown current TD. Cc: <stable@vger.kernel.org> cc: Jeremy Compostella <jeremy.compostella@intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20200421140822.28233-2-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>