linux/drivers/usb/host
Julius Werner 1f81b6d22a usb: xhci: Prefer endpoint context dequeue pointer over stopped_trb
We have observed a rare cycle state desync bug after Set TR Dequeue
Pointer commands on Intel LynxPoint xHCs (resulting in an endpoint that
doesn't fetch new TRBs and thus an unresponsive USB device). It always
triggers when a previous Set TR Dequeue Pointer command has set the
pointer to the final Link TRB of a segment, and then another URB gets
enqueued and cancelled again before it can be completed. Further
investigation showed that the xHC had returned the Link TRB in the TRB
Pointer field of the Transfer Event (CC == Stopped -- Length Invalid),
but when xhci_find_new_dequeue_state() later accesses the Endpoint
Context's TR Dequeue Pointer field it is set to the first TRB of the
next segment.

The driver expects those two values to be the same in this situation,
and uses the cycle state of the latter together with the address of the
former. This should be fine according to the XHCI specification, since
the endpoint ring should be stopped when returning the Transfer Event
and thus should not advance over the Link TRB before it gets restarted.
However, real-world XHCI implementations apparently don't really care
that much about these details, so the driver should follow a more
defensive approach to try to work around HC spec violations.

This patch removes the stopped_trb variable that had been used to store
the TRB Pointer from the last Transfer Event of a stopped TRB. Instead,
xhci_find_new_dequeue_state() now relies only on the Endpoint Context,
requiring a small amount of additional processing to find the virtual
address corresponding to the TR Dequeue Pointer. Some other parts of the
function were slightly rearranged to better fit into this model.

This patch should be backported to kernels as old as 2.6.31 that contain
the commit ae63674714 "USB: xhci: URB
cancellation support."

Signed-off-by: Julius Werner <jwerner@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-25 09:34:10 -07:00
..
whci usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00
bcma-hcd.c DMA-API: usb: bcma: replace dma_set_mask()+dma_set_coherent_mask() with new helper 2013-10-31 14:48:34 +00:00
ehci-atmel.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-dbg.c usb: Use dev_is_pci() to check whether it is pci device 2013-12-08 18:01:56 -08:00
ehci-exynos.c usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails 2014-04-16 13:59:13 -07:00
ehci-fsl.c USB: ehci-fsl: Use devm_ioremap_resource() 2013-12-18 16:33:47 -08:00
ehci-fsl.h
ehci-grlib.c USB: ehci-grlib: use dev_err() instead of printk() 2013-12-18 16:32:41 -08:00
ehci-hcd.c usb: ehci: fix deadlock when threadirqs option is used 2014-02-26 15:46:42 -08:00
ehci-hub.c USB: EHCI: add delay during suspend to prevent erroneous wakeups 2014-02-18 12:04:41 -08:00
ehci-mem.c USB: EHCI: fix sparse errors 2013-10-19 14:08:04 -07:00
ehci-msm.c USB: ehci-msm: Add device tree support and binding information 2013-10-11 16:31:15 -07:00
ehci-mv.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-mxc.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-octeon.c USB: ehci-octeon: Use devm_ioremap_resource() 2013-12-18 16:34:20 -08:00
ehci-omap.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-orion.c USB: ehci-orion: Use devm_*() functions 2013-12-18 16:33:47 -08:00
ehci-pci.c usb: ehci: use amd_chipset_type to filter for usb subsystem hang bug 2013-10-03 15:44:50 -07:00
ehci-platform.c usb: ehci-platform: Return immediately from suspend if ehci_suspend fails 2014-04-16 13:59:13 -07:00
ehci-pmcmsp.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-ppc-of.c USB: ehci-ppc-of: use dev_err() instead of printk() 2013-12-18 16:32:41 -08:00
ehci-ps3.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-q.c usb: kill DEBUG compile option 2013-12-03 10:34:33 -08:00
ehci-sched.c USB: EHCI: fix sparse errors 2013-10-19 14:08:04 -07:00
ehci-sead3.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-sh.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-spear.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-sysfs.c USB: EHCI: use a bandwidth-allocation table 2013-10-11 16:45:43 -07:00
ehci-tegra.c USB: EHCI: tegra: set txfill_tuning 2014-04-16 13:59:13 -07:00
ehci-tilegx.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ehci-timer.c USB: EHCI: improve interrupt qh unlink 2013-08-12 11:43:48 -07:00
ehci-w90x900.c USB: ehci-w90x900: Use devm_ioremap_resource() 2013-12-18 16:35:11 -08:00
ehci-xilinx-of.c USB: ehci-xilinx-of: use dev_err() instead of printk() 2013-12-18 16:32:41 -08:00
ehci.h usb: ehci: add freescale imx28 special write register method 2014-01-13 15:54:03 -08:00
fhci-dbg.c
fhci-hcd.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
fhci-hub.c
fhci-mem.c
fhci-q.c
fhci-sched.c
fhci-tds.c
fhci.h
fotg210-hcd.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
fotg210.h fotg210: remove conditional compilation 2013-12-03 10:28:39 -08:00
fsl-mph-dr-of.c USB: fsl-mph-dr-of: adjust for OF based clock lookup 2014-01-12 18:53:05 +01:00
fusbh200-hcd.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
fusbh200.h fusb200h: always compile in debugfs support 2013-12-03 10:31:21 -08:00
hwa-hc.c usb: wusbcore: disable transfer notifications for Alereon HWAs 2014-03-07 12:52:04 -08:00
imx21-dbg.c usb: kill DEBUG compile option 2013-12-03 10:34:33 -08:00
imx21-hcd.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
imx21-hcd.h usb: kill DEBUG compile option 2013-12-03 10:34:33 -08:00
isp116x-hcd.c usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00
isp116x.h
isp1362-hcd.c usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00
isp1362.h USB: isp1362: move debug files from proc to debugfs 2013-07-24 14:43:05 -07:00
isp1760-hcd.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
isp1760-hcd.h
isp1760-if.c USB: host: use dev_get_platdata() 2013-07-31 17:53:50 -07:00
Kconfig Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2014-04-02 16:23:38 -07:00
Makefile usb: kill DEBUG compile option 2013-12-03 10:34:33 -08:00
octeon2-common.c
ohci-at91.c USB: fix: ohci-at91 mismerge build error 2014-01-07 09:30:48 -08:00
ohci-da8xx.c USB: ohci-da8xx: Use devm_*() functions 2013-12-18 16:35:11 -08:00
ohci-dbg.c ohci: remove conditional compilation 2013-12-03 10:25:22 -08:00
ohci-exynos.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ohci-hcd.c USB: OHCI: Properly handle OHCI controller suspend 2013-12-08 17:53:17 -08:00
ohci-hub.c ohci: no conditional debugging in root hub hadling 2013-12-03 10:25:22 -08:00
ohci-jz4740.c USB: ohci-jz4740: FEAT_POWER is a port feature, not a hub feature 2014-04-16 13:59:41 -07:00
ohci-mem.c
ohci-nxp.c USB: ohci-nxp: Use devm_clk_get() 2013-12-18 16:36:10 -08:00
ohci-octeon.c USB: ohci-octeon: Use devm_ioremap_resource() 2013-12-18 16:36:11 -08:00
ohci-omap3.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ohci-omap.c USB: ohci-omap: use dev_err() instead of printk() 2013-12-18 16:32:41 -08:00
ohci-pci.c usb: ohci: use amd_chipset_type to filter for SB800 prefetch 2013-10-03 15:44:51 -07:00
ohci-platform.c USB: ohci-platform: check for platform data misconfiguration 2014-02-11 13:39:54 -08:00
ohci-ppc-of.c USB: ohci-ppc-of: Use devm_ioremap_resource() 2013-12-18 16:36:10 -08:00
ohci-ps3.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ohci-pxa27x.c USB: ohci-pxa27x:Use devm_*() functions 2013-12-18 16:35:10 -08:00
ohci-q.c ohci: kill ohci_vdbg 2013-12-03 10:25:22 -08:00
ohci-s3c2410.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ohci-sa1111.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ohci-sm501.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ohci-spear.c USB: ohci-spear: Use devm_ioremap_resource() 2013-12-18 16:36:11 -08:00
ohci-tilegx.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
ohci-tmio.c usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00
ohci.h ohci: kill ohci_vdbg 2013-12-03 10:25:22 -08:00
oxu210hp-hcd.c usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00
oxu210hp.h
pci-quirks.c usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00
pci-quirks.h usb: ohci: use amd_chipset_type to filter for SB800 prefetch 2013-10-03 15:44:51 -07:00
r8a66597-hcd.c ARM: driver updates for 3.14 2014-01-23 18:49:36 -08:00
r8a66597.h
sl811_cs.c usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00
sl811-hcd.c usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00
sl811.h USB: sl811: move debug files from proc to debugfs 2013-07-24 14:43:05 -07:00
ssb-hcd.c DMA-API: usb: ssb-hcd: replace dma_set_mask()+dma_set_coherent_mask() with new helper 2013-10-31 14:48:36 +00:00
u132-hcd.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
uhci-debug.c usb: kill DEBUG compile option 2013-12-03 10:34:33 -08:00
uhci-grlib.c usb: hcd: move controller wakeup setting initialization to individual driver 2013-12-08 18:06:46 -08:00
uhci-hcd.c usb: kill DEBUG compile option 2013-12-03 10:34:33 -08:00
uhci-hcd.h
uhci-hub.c USB/host: Bugfix: Return length of copied buffer in uhci_hub_control() 2013-10-07 00:07:17 -07:00
uhci-pci.c USB: remove DEFINE_PCI_DEVICE_TABLE macro 2013-12-04 16:58:47 -08:00
uhci-platform.c uhci-platform: Change compatible string from platform-uhci to generic-uhci 2014-02-15 12:25:51 -08:00
uhci-q.c USB: UHCI: accept very late isochronous URBs 2013-09-25 17:05:34 -07:00
xhci-dbg.c Revert "xhci: replace xhci_read_64() with readq()" 2014-01-30 13:27:49 -08:00
xhci-ext-caps.h xhci: fix port BESL LPM capability checking 2013-08-27 08:54:42 -07:00
xhci-hub.c usb/xhci: Change how we indicate a host supports Link PM. 2014-03-04 15:38:00 -08:00
xhci-mem.c xhci: The trb_address_map radix tree expects 1KB segment memory aligment 2014-03-04 15:38:14 -08:00
xhci-pci.c xhci: Prevent runtime pm from autosuspending during initialization 2014-03-06 13:46:55 -08:00
xhci-plat.c storage: accept some UAS devices if streams are unavailable 2014-03-04 15:41:09 -08:00
xhci-ring.c usb: xhci: Prefer endpoint context dequeue pointer over stopped_trb 2014-04-25 09:34:10 -07:00
xhci-trace.c xhci: add traces for debug messages in xhci_address_device() 2013-08-13 16:05:38 -07:00
xhci-trace.h xhci: fix sparse warning in xhci-trace.h 2013-12-02 12:59:45 -08:00
xhci.c usb: xhci: Prefer endpoint context dequeue pointer over stopped_trb 2014-04-25 09:34:10 -07:00
xhci.h usb: xhci: Prefer endpoint context dequeue pointer over stopped_trb 2014-04-25 09:34:10 -07:00