linux-stable.git/drivers/usb/host, branch v6.14.2

usb: xhci: correct debug message page size calculation

2025-04-10T12:44:30+00:00

[ Upstream commit 55741c723318905e6d5161bf1e12749020b161e3 ]

The ffs() function returns the index of the first set bit, starting from 1.
If no bits are set, it returns zero. This behavior causes an off-by-one
page size in the debug message, as the page size calculation [1]
is zero-based, while ffs() is one-based.

Fix this by subtracting one from the result of ffs(). Note that since
variable 'val' is unsigned, subtracting one from zero will result in the
maximum unsigned integer value. Consequently, the condition 'if (val < 16)'
will still function correctly.

[1], Page size: (2^(n+12)), where 'n' is the set page size bit.

Fixes: 81720ec5320c ("usb: host: xhci: use ffs() in xhci_mem_init()")
Signed-off-by: Niklas Neronin 
Signed-off-by: Mathias Nyman 
Link: https://lore.kernel.org/r/20250306144954.3507700-9-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

usb: xhci: Apply the link chain quirk on NEC isoc endpoints

2025-04-07T08:11:12+00:00

commit bb0ba4cb1065e87f9cc75db1fa454e56d0894d01 upstream.

Two clearly different specimens of NEC uPD720200 (one with start/stop
bug, one without) were seen to cause IOMMU faults after some Missed
Service Errors. Faulting address is immediately after a transfer ring
segment and patched dynamic debug messages revealed that the MSE was
received when waiting for a TD near the end of that segment:

[ 1.041954] xhci_hcd: Miss service interval error for slot 1 ep 2 expected TD DMA ffa08fe0
[ 1.042120] xhci_hcd: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0005 address=0xffa09000 flags=0x0000]
[ 1.042146] xhci_hcd: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0005 address=0xffa09040 flags=0x0000]

It gets even funnier if the next page is a ring segment accessible to
the HC. Below, it reports MSE in segment at ff1e8000, plows through a
zero-filled page at ff1e9000 and starts reporting events for TRBs in
page at ff1ea000 every microframe, instead of jumping to seg ff1e6000.

[ 7.041671] xhci_hcd: Miss service interval error for slot 1 ep 2 expected TD DMA ff1e8fe0
[ 7.041999] xhci_hcd: Miss service interval error for slot 1 ep 2 expected TD DMA ff1e8fe0
[ 7.042011] xhci_hcd: WARN: buffer overrun event for slot 1 ep 2 on endpoint
[ 7.042028] xhci_hcd: All TDs skipped for slot 1 ep 2. Clear skip flag.
[ 7.042134] xhci_hcd: WARN: buffer overrun event for slot 1 ep 2 on endpoint
[ 7.042138] xhci_hcd: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 2 comp_code 31
[ 7.042144] xhci_hcd: Looking for event-dma 00000000ff1ea040 trb-start 00000000ff1e6820 trb-end 00000000ff1e6820
[ 7.042259] xhci_hcd: WARN: buffer overrun event for slot 1 ep 2 on endpoint
[ 7.042262] xhci_hcd: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 2 comp_code 31
[ 7.042266] xhci_hcd: Looking for event-dma 00000000ff1ea050 trb-start 00000000ff1e6820 trb-end 00000000ff1e6820

At some point completion events change from Isoch Buffer Overrun to
Short Packet and the HC finally finds cycle bit mismatch in ff1ec000.

[ 7.098130] xhci_hcd: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 2 comp_code 13
[ 7.098132] xhci_hcd: Looking for event-dma 00000000ff1ecc50 trb-start 00000000ff1e6820 trb-end 00000000ff1e6820
[ 7.098254] xhci_hcd: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 2 comp_code 13
[ 7.098256] xhci_hcd: Looking for event-dma 00000000ff1ecc60 trb-start 00000000ff1e6820 trb-end 00000000ff1e6820
[ 7.098379] xhci_hcd: Overrun event on slot 1 ep 2

It's possible that data from the isochronous device were written to
random buffers of pending TDs on other endpoints (either IN or OUT),
other devices or even other HCs in the same IOMMU domain.

Lastly, an error from a different USB device on another HC. Was it
caused by the above? I don't know, but it may have been. The disk
was working without any other issues and generated PCIe traffic to
starve the NEC of upstream BW and trigger those MSEs. The two HCs
shared one x1 slot by means of a commercial "PCIe splitter" board.

[ 7.162604] usb 10-2: reset SuperSpeed USB device number 3 using xhci_hcd
[ 7.178990] sd 9:0:0:0: [sdb] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x07 driverbyte=DRIVER_OK cmd_age=0s
[ 7.179001] sd 9:0:0:0: [sdb] tag#0 CDB: opcode=0x28 28 00 04 02 ae 00 00 02 00 00
[ 7.179004] I/O error, dev sdb, sector 67284480 op 0x0:(READ) flags 0x80700 phys_seg 5 prio class 0

Fortunately, it appears that this ridiculous bug is avoided by setting
the chain bit of Link TRBs on isochronous rings. Other ancient HCs are
known which also expect the bit to be set and they ignore Link TRBs if
it's not. Reportedly, 0.95 spec guaranteed that the bit is set.

The bandwidth-starved NEC HC running a 32KB/uframe UVC endpoint reports
tens of MSEs per second and runs into the bug within seconds. Chaining
Link TRBs allows the same workload to run for many minutes, many times.

No negative side effects seen in UVC recording and UAC playback with a
few devices at full speed, high speed and SuperSpeed.

The problem doesn't reproduce on the newer Renesas uPD720201/uPD720202
and on old Etron EJ168 and VIA VL805 (but the VL805 has other bug).

[shorten line length of log snippets in commit messge -Mathias]

Signed-off-by: Michal Pecio 
Cc: stable@vger.kernel.org
Signed-off-by: Mathias Nyman 
Link: https://lore.kernel.org/r/20250306144954.3507700-14-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

usb: xhci: Don't skip on Stopped - Length Invalid

2025-04-07T08:11:12+00:00

commit 58d0a3fab5f4fdc112c16a4c6d382f62097afd1c upstream.

Up until commit d56b0b2ab142 ("usb: xhci: ensure skipped isoc TDs are
returned when isoc ring is stopped") in v6.11, the driver didn't skip
missed isochronous TDs when handling Stoppend and Stopped - Length
Invalid events. Instead, it erroneously cleared the skip flag, which
would cause the ring to get stuck, as future events won't match the
missed TD which is never removed from the queue until it's cancelled.

This buggy logic seems to have been in place substantially unchanged
since the 3.x series over 10 years ago, which probably speaks first
and foremost about relative rarity of this case in normal usage, but
by the spec I see no reason why it shouldn't be possible.

After d56b0b2ab142, TDs are immediately skipped when handling those
Stopped events. This poses a potential problem in case of Stopped -
Length Invalid, which occurs either on completed TDs (likely already
given back) or Link and No-Op TRBs. Such event won't be recognized
as matching any TD (unless it's the rare Link TRB inside a TD) and
will result in skipping all pending TDs, giving them back possibly
before they are done, risking isoc data loss and maybe UAF by HW.

As a compromise, don't skip and don't clear the skip flag on this
kind of event. Then the next event will skip missed TDs. A downside
of not handling Stopped - Length Invalid on a Link inside a TD is
that if the TD is cancelled, its actual length will not be updated
to account for TRBs (silently) completed before the TD was stopped.

I had no luck producing this sequence of completion events so there
is no compelling demonstration of any resulting disaster. It may be
a very rare, obscure condition. The sole motivation for this patch
is that if such unlikely event does occur, I'd rather risk reporting
a cancelled partially done isoc frame as empty than gamble with UAF.

This will be fixed more properly by looking at Stopped event's TRB
pointer when making skipping decisions, but such rework is unlikely
to be backported to v6.12, which will stay around for a few years.

Fixes: d56b0b2ab142 ("usb: xhci: ensure skipped isoc TDs are returned when isoc ring is stopped")
Cc: stable@vger.kernel.org
Signed-off-by: Michal Pecio 
Signed-off-by: Mathias Nyman 
Link: https://lore.kernel.org/r/20250306144954.3507700-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

usb: xhci: Fix host controllers "dying" after suspend and resume

2025-03-04T14:02:24+00:00

A recent cleanup went a bit too far and dropped clearing the cycle bit
of link TRBs, so it stays different from the rest of the ring half of
the time. Then a race occurs: if the xHC reaches such link TRB before
more commands are queued, the link's cycle bit unintentionally matches
the xHC's cycle so it follows the link and waits for further commands.
If more commands are queued before the xHC gets there, inc_enq() flips
the bit so the xHC later sees a mismatch and stops executing commands.

This function is called before suspend and 50% of times after resuming
the xHC is doomed to get stuck sooner or later. Then some Stop Endpoint
command fails to complete in 5 seconds and this shows up

xhci_hcd 0000:00:10.0: xHCI host not responding to stop endpoint command
xhci_hcd 0000:00:10.0: xHCI host controller not responding, assume dead
xhci_hcd 0000:00:10.0: HC died; cleaning up

followed by loss of all USB decives on the affected bus. That's if you
are lucky, because if Set Deq gets stuck instead, the failure is silent.

Likely responsible for kernel bug 219824. I found this while searching
for possible causes of that regression and reproduced it locally before
hearing back from the reporter. To repro, simply wait for link cycle to
become set (debugfs), then suspend, resume and wait. To accelerate the
failure I used a script which repeatedly starts and stops a UVC camera.

Some HCs get fully reinitialized on resume and they are not affected.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=219824
Fixes: 36b972d4b7ce ("usb: xhci: improve xhci_clear_command_ring()")
Cc: stable@vger.kernel.org
Signed-off-by: Michal Pecio 
Signed-off-by: Mathias Nyman 
Link: https://lore.kernel.org/r/20250304113147.3322584-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

xhci: Restrict USB4 tunnel detection for USB3 devices to Intel hosts

2025-03-03T09:10:06+00:00

When adding support for USB3-over-USB4 tunnelling detection, a check
for an Intel-specific capability was added. This capability, which
goes by ID 206, is used without any check that we are actually
dealing with an Intel host.

As it turns out, the Cadence XHCI controller *also* exposes an
extended capability numbered 206 (for unknown purposes), but of
course doesn't have the Intel-specific registers that the tunnelling
code is trying to access. Fun follows.

The core of the problems is that the tunnelling code blindly uses
vendor-specific capabilities without any check (the Intel-provided
documentation I have at hand indicates that 192-255 are indeed
vendor-specific).

Restrict the detection code to Intel HW for real, preventing any
further explosion on my (non-Intel) HW.

Cc: stable 
Fixes: 948ce83fbb7df ("xhci: Add USB4 tunnel detection for USB3 devices on Intel hosts")
Signed-off-by: Marc Zyngier 
Acked-by: Mathias Nyman 
Link: https://lore.kernel.org/r/20250227194529.2288718-1-maz@kernel.org
Signed-off-by: Greg Kroah-Hartman

usb: xhci: Enable the TRB overfetch quirk on VIA VL805

2025-02-27T20:22:24+00:00

Raspberry Pi is a major user of those chips and they discovered a bug -
when the end of a transfer ring segment is reached, up to four TRBs can
be prefetched from the next page even if the segment ends with link TRB
and on page boundary (the chip claims to support standard 4KB pages).

It also appears that if the prefetched TRBs belong to a different ring
whose doorbell is later rung, they may be used without refreshing from
system RAM and the endpoint will stay idle if their cycle bit is stale.

Other users complain about IOMMU faults on x86 systems, unsurprisingly.

Deal with it by using existing quirk which allocates a dummy page after
each transfer ring segment. This was seen to resolve both problems. RPi
came up with a more efficient solution, shortening each segment by four
TRBs, but it complicated the driver and they ditched it for this quirk.

Also rename the quirk and add VL805 device ID macro.

Signed-off-by: Michal Pecio 
Link: https://github.com/raspberrypi/linux/issues/4685
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=215906
CC: stable@vger.kernel.org
Signed-off-by: Mathias Nyman 
Link: https://lore.kernel.org/r/20250225095927.2512358-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

usb: xhci: Restore xhci_pci support for Renesas HCs

2025-02-14T08:21:24+00:00

Some Renesas HCs require firmware upload to work, this is handled by the
xhci_pci_renesas driver. Other variants of those chips load firmware from
a SPI flash and are ready to work with xhci_pci alone.

A refactor merged in v6.12 broke the latter configuration so that users
are finding their hardware ignored by the normal driver and are forced to
enable the firmware loader which isn't really necessary on their systems.

Let xhci_pci work with those chips as before when the firmware loader is
disabled by kernel configuration.

Fixes: 25f51b76f90f ("xhci-pci: Make xhci-pci-renesas a proper modular driver")
Cc: stable 
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219616
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219726
Signed-off-by: Michal Pecio 
Tested-by: Nicolai Buchwitz 
Link: https://lore.kernel.org/r/20250128104529.58a79bfc@foxbook
Signed-off-by: Greg Kroah-Hartman

USB: pci-quirks: Fix HCCPARAMS register error for LS7A EHCI

2025-02-14T08:18:14+00:00

LS7A EHCI controller doesn't have extended capabilities, so the EECP
(EHCI Extended Capabilities Pointer) field of HCCPARAMS register should
be 0x0, but it reads as 0xa0 now. This is a hardware flaw and will be
fixed in future, now just clear the EECP field to avoid error messages
on boot:

......
[    0.581675] pci 0000:00:04.1: EHCI: unrecognized capability ff
[    0.581699] pci 0000:00:04.1: EHCI: unrecognized capability ff
[    0.581716] pci 0000:00:04.1: EHCI: unrecognized capability ff
[    0.581851] pci 0000:00:04.1: EHCI: unrecognized capability ff
......
[    0.581916] pci 0000:00:05.1: EHCI: unrecognized capability ff
[    0.581951] pci 0000:00:05.1: EHCI: unrecognized capability ff
[    0.582704] pci 0000:00:05.1: EHCI: unrecognized capability ff
[    0.582799] pci 0000:00:05.1: EHCI: unrecognized capability ff
......

Cc: stable 
Signed-off-by: Baoqi Zhang 
Signed-off-by: Huacai Chen 
Link: https://lore.kernel.org/r/20250202124935.480500-1-chenhuacai@loongson.cn
Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2025-01-28T20:25:12+00:00

Pull driver core and debugfs updates from Greg KH:
 "Here is the big set of driver core and debugfs updates for 6.14-rc1.

  Included in here is a bunch of driver core, PCI, OF, and platform rust
  bindings (all acked by the different subsystem maintainers), hence the
  merge conflict with the rust tree, and some driver core api updates to
  mark things as const, which will also require some fixups due to new
  stuff coming in through other trees in this merge window.

  There are also a bunch of debugfs updates from Al, and there is at
  least one user that does have a regression with these, but Al is
  working on tracking down the fix for it. In my use (and everyone
  else's linux-next use), it does not seem like a big issue at the
  moment.

  Here's a short list of the things in here:

   - driver core rust bindings for PCI, platform, OF, and some i/o
     functions.

     We are almost at the "write a real driver in rust" stage now,
     depending on what you want to do.

   - misc device rust bindings and a sample driver to show how to use
     them

   - debugfs cleanups in the fs as well as the users of the fs api for
     places where drivers got it wrong or were unnecessarily doing
     things in complex ways.

   - driver core const work, making more of the api take const * for
     different parameters to make the rust bindings easier overall.

   - other small fixes and updates

  All of these have been in linux-next with all of the aforementioned
  merge conflicts, and the one debugfs issue, which looks to be resolved
  "soon""

* tag 'driver-core-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits)
  rust: device: Use as_char_ptr() to avoid explicit cast
  rust: device: Replace CString with CStr in property_present()
  devcoredump: Constify 'struct bin_attribute'
  devcoredump: Define 'struct bin_attribute' through macro
  rust: device: Add property_present()
  saner replacement for debugfs_rename()
  orangefs-debugfs: don't mess with ->d_name
  octeontx2: don't mess with ->d_parent or ->d_parent->d_name
  arm_scmi: don't mess with ->d_parent->d_name
  slub: don't mess with ->d_name
  sof-client-ipc-flood-test: don't mess with ->d_name
  qat: don't mess with ->d_name
  xhci: don't mess with ->d_iname
  mtu3: don't mess wiht ->d_iname
  greybus/camera - stop messing with ->d_iname
  mediatek: stop messing with ->d_iname
  netdevsim: don't embed file_operations into your structs
  b43legacy: make use of debugfs_get_aux()
  b43: stop embedding struct file_operations into their objects
  carl9170: stop embedding file_operations into their objects
  ...

usb: xhci: tegra: Fix OF boolean read warning

2025-01-17T11:39:42+00:00

After commit c141ecc3cecd ("of: Warn when of_property_read_bool() is
used on non-boolean properties") was added, the following warning is
observed for the Tegra XHCI driver ...

 OF: /bus@0/usb@3610000: Read of boolean property 'power-domains' with
     a value.

Previously, of_property_read_bool() was used to determine if a property
was present but has now been replaced by of_property_present(). The
warning is meant to prevent new users but this user existed before the
change was made. Fix this by updating the Tegra XHCI driver to use
of_property_present() function to determine if the 'power-domains'
property is present.

Signed-off-by: Jon Hunter 
Link: https://lore.kernel.org/r/20250116153829.477360-1-jonathanh@nvidia.com
Signed-off-by: Greg Kroah-Hartman