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New: DMAR fault when connected usb hub (xhci_hcd)

Bug 215906 [email protected] 1 participant 32 messages Apr 27, 2022 – Mar 18 USB

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#0 lore raw

https://bugzilla.kernel.org/show_bug.cgi?id=215906

            Bug ID: 215906
           Summary: DMAR fault when connected usb hub (xhci_hcd)
           Product: Drivers
           Version: 2.5
    Kernel Version: Tested on 5.15.0-27,  5.17.0-051700-generic (from
                    https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.17/)
          Hardware: x86-64
                OS: Linux
              Tree: Mainline
            Status: NEW
          Severity: normal
          Priority: P1
         Component: USB
          Assignee: [email protected]
          Reporter: [email protected]
        Regression: Yes

Since kernel 5.15 (with kernel 5.13 I see no problem) I have a problem with my USB hub. The device stops working shortly after starting the system. In dmesg log I see DMAR fault on usb controller

[kwi27 22:03] usb 5-1.2: new high-speed USB device number 3 using xhci_hcd [ +0,100440] usb 5-1.2: New USB device found, idVendor=1a40, idProduct=0101, bcdDevice= 1.11
[ +0,000004] usb 5-1.2: New USB device strings: Mfr=0, Product=1, SerialNumber=0

[  +0,000002] usb 5-1.2: Product: USB 2.0 Hub
[  +0,001002] hub 5-1.2:1.0: USB hub found
[  +0,000133] hub 5-1.2:1.0: 4 ports detected
[  +0,702453] usb 5-1.2.2: new full-speed USB device number 4 using xhci_hcd
[  +0,471198] usb 5-1.2.2: New USB device found, idVendor=047f, idProduct=c025,
bcdDevice= 1.35
[  +0,000004] usb 5-1.2.2: New USB device strings: Mfr=1, Product=2,
SerialNumber=3
[  +0,000002] usb 5-1.2.2: Product: Plantronics C320-M
[  +0,000001] usb 5-1.2.2: Manufacturer: Plantronics
[  +0,000001] usb 5-1.2.2: SerialNumber: B13D8BE491B04E73AEB4C95E162DBE2B
[  +0,255862] mc: Linux media interface: v0.10
[  +0,001057] input: Plantronics Plantronics C320-M as

/devices/pci0000:00/0000:00:1c.5/0000:04:00.0/usb5/5-1/5-1.2/5-1.2.2/5-1.2.2:1.3/0003:047F:C025.0004/input/input21 [ +0,060275] plantronics 0003:047F:C025.0004: input,hiddev1,hidraw3: USB HID
v1.11 Device [Plantronics Plantronics C320-M] on usb-0000:04:00.0-1.2.2/input3
[ +0,859655] usb 5-1.2.2: Warning! Unlikely big volume range (=8192),
cval->res is probably wrong.
[ +0,000003] usb 5-1.2.2: [11] FU [Sidetone Playback Volume] ch = 1, val =
0/8192/1

[  +0,584234] usbcore: registered new interface driver snd-usb-audio
[  +0,229229] xhci_hcd 0000:04:00.0: WARNING: Host System Error
[  +0,000014] DMAR: DRHD: handling fault status reg 2
[  +0,000004] DMAR: [DMA Read NO_PASID] Request device [04:00.0] fault addr

0xfffca000 [fault reason 0x06] PTE Read access is not set
[ +0,031993] xhci_hcd 0000:04:00.0: Host halt failed, -110 [kwi27 22:04] xhci_hcd 0000:04:00.0: xHCI host not responding to stop endpoint command.

[  +0,000003] xhci_hcd 0000:04:00.0: USBSTS: HSE EINT
[  +0,032011] xhci_hcd 0000:04:00.0: Host halt failed, -110
[  +0,000002] xhci_hcd 0000:04:00.0: xHCI host controller not responding,
assume dead
[  +0,000017] xhci_hcd 0000:04:00.0: HC died; cleaning up
[  +0,000042] usb 5-1: USB disconnect, device number 2
[  +0,000003] usb 5-1.2: USB disconnect, device number 3
[  +0,000002] usb 5-1.2.2: USB disconnect, device number 4
[  +0,000114] usb 5-1.2.2: 1:0: usb_set_interface failed (-110)
[  +0,000016] usb 5-1.2.2: 1:1: usb_set_interface failed (-19)
[  +0,000011] usb 5-1.2.2: 1:0: usb_set_interface failed (-19)

04:00.0 USB controller: VIA Technologies, Inc. VL805/806 xHCI USB 3.0 Controller (rev 01) (prog-if 30 [XHCI])
Subsystem: Micro-Star International Co., Ltd. [MSI] VL805/806 xHCI USB
3.0 Controller
Flags: bus master, fast devsel, latency 0, IRQ 31, IOMMU group 12 Memory at f7100000 (64-bit, non-prefetchable) [size=4K]
Capabilities: <access denied>
Kernel driver in use: xhci_hcd
Kernel modules: xhci_pci

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#1 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #1 from Royston Shufflebotham ([email protected]) --- I just hit exactly the same issue when upgrading the kernel from v5.13.0-40 to v5.15.0-27. With no devices plugged in, the USB hub reports everything as ok. Plugging in a USB keyboard worked for a minute or two, and then I get exactly the same errors from [+0,229229] to [+0,000004] above.

Same USB controller chipset as OP by the looks of things. I've managed to list the Capabilities in case that's any help:
03:00.0 USB controller: VIA Technologies, Inc. VL805/806 xHCI USB 3.0 Controller (rev 01) (prog-if 30 [XHCI])
Subsystem: VIA Technologies, Inc. VL805/806 xHCI USB 3.0 Controller
Flags: bus master, fast devsel, latency 0, IRQ 28, IOMMU group 12 Memory at e0a00000 (64-bit, non-prefetchable) [size=4K]
Capabilities: [80] Power Management version 3
Capabilities: [90] MSI: Enable+ Count=1/4 Maskable- 64bit+
Capabilities: [c4] Express Endpoint, MSI 00
Capabilities: [100] Advanced Error Reporting
Kernel driver in use: xhci_hcd
Kernel modules: xhci_pci

Downgrading back to v5.13.0-40 fixes the problem.

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#2 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |[email protected]

--- Comment #2 from The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) --- I wanted to add this issue to the regression tracking and poke the maintainers,
but noticed there is a patch that is being backported right now that might or
might not be related (not my area of expertise):
https://lore.kernel.org/all/[email protected]/

It's already in 5.18-rc5; could somebody please give it a quick try before I proceed with my initial plan?

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#4 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #4 from Piotr Piórkowski ([email protected]) ---
I've misled you a bit by saying that the bug didn't occur on the 5.13 kernel. I tried bisecting on the upstream kernel and it turns out that the problem also occurs on the 5.13 - I build it using ubuntu default config from kernel 5.15.0-27.

So far, the only kernel build I haven't noticed a problem with (excluding kernels 5.4 from Ubuntu 20.04 LTS) is kernel 5.13.0-28-generic form Ubuntu.

Interestingly, I found the sources of this kernel on git kernel.ubuntu.com and built this kernel using this config from kernel 5.15 and the problem also occurred.

It was only when I built this kernel using the default config for this kernel that I stopped seeing the problem.

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#5 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #5 from The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) --- Sorry, this is starting to get confusing and hard to follow.

If there is something that used to work with an Ubuntu kernel and stops working there, you might want to report it to the Ubuntu developers, but not here.

This bug tracker care mainly about upstream kernel (see front page), so what happens with a kernel build from the Ubuntu sources (which are known to be modified a lot) is irrelevant and even just mentioning that makes things hard to follow. :-/

Regarding your problem: I'm not familiar with the code that might cause this, but to me it looks a lot like Ubuntu switched on a kernel configuration option that is causing this. If that's the case the problem doesn't qualify as regression, as explained here:
https://www.kernel.org/doc/html/latest/admin-guide/reporting-issues.html

The developers nevertheless might be interested in fixing this, but might need more details from you (like the config option that is causing this)

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#6 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

Mathias Nyman ([email protected]) changed:

What |Removed |Added
----------------------------------------------------------------------------

                 CC|                            |[email protected]
                   |                            |om

--- Comment #6 from Mathias Nyman ([email protected]) --- [ +0,229229] xhci_hcd 0000:04:00.0: WARNING: Host System Error

The xHC controller reports a catastrophic error, and sets HSE bit.

For PCI xHC controllers the spec lists possible causes as:
host controller PCI parity error, PCI Master Abort, PCI Target Abort. But DMA issues also possible cause, especially as log shows DMAR problems right after this.

Any chance you could bisect this on upstream kernel?

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#7 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #7 from Piotr Piórkowski ([email protected]) --- @Thorsten Leemhuis sorry for misleading you but when adding this bug here, I didn't know it wasn't an upstream regression - at first look it looked that way, as I also observed the problem on the upstream.

So far we only know that in one of the kernel configurations the problem does not occur - but this does not mean that the problem does not exist.

Quoted 1 line

Any chance you could bisect this on upstream kernel?

I'll try to do it this week

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#8 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #8 from The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) --- (In reply to Piotr Piórkowski from comment #7)

Quoted 3 lines
Quoted 2 lines

Any chance you could bisect this on upstream kernel?

I'll try to do it this week

And news? Was the issue maybe fixed meanwhile?

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#9 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

Chris Bainbridge ([email protected]) changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |[email protected]

--- Comment #9 from Chris Bainbridge ([email protected]) --- The IOMMU error is caused by a buggy VL805 firmware. It is more visible with the Debian kernel as Debian patches the kernel to enable IOMMU by default. The updated firmware can be installed using the VIA Windows tool (this did not work for me), or you can just turn off IOMMU.

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#10 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #10 from The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) --- (In reply to Chris Bainbridge from comment #9)

Quoted 1 line

The IOMMU error is caused by a buggy VL805 firmware.

Makes me wonder: would it be possible to detect an old firmware and avoid the IOMMU path in this case? Or at least warn?

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#11 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #11 from Chris Bainbridge ([email protected]) --- (In reply to The Linux kernel's regression tracker (Thorsten Leemhuis) from comment #10)

Quoted 5 lines

(In reply to Chris Bainbridge from comment #9)

Quoted 1 line

The IOMMU error is caused by a buggy VL805 firmware.

Makes me wonder: would it be possible to detect an old firmware and avoid the IOMMU path in this case? Or at least warn?

It would be possible to detect, the firmware version can be read with:

$ sudo lspci -d 1106:3483 -xxx | awk '/^50:/ { print "VL805 FW version: " $5 $4
$3 $2 }'
VL805 FW version: 00013500

imho it would be a good idea for Linux to track the latest firmware versions for *all* hardware and warn if a firmware is out-of-date (even if the firmware updater is only available on Windows). Earlier this year I had an intermittent issue with a new laptop where the desktop would hang and processes would get IO errors. But this only happened once every 3 weeks or so. It took a few months to isolate the problem to NVME firmware (it was a HP laptop with Intel NVME, and I was unaware that these drives have locked HP-specific firmware). The firmware update was a Windows executable. I've also seen many forum posts where people have problems that were resolved by updates to GPU/motherboard/NVME/ethernet/wifi etc. firmware. Many of these problems could have been resolved a lot quicker if the kernel log contained "old firmware detected!".

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#12 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #12 from The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) --- (In reply to Chris Bainbridge from comment #11)

Quoted 1 line

It would be possible to detect […]

Thx for that.

Quoted 2 lines

imho it would be a good idea for Linux to track the latest firmware versions for *all* hardware […]

Pretty sure that is something that should be done in userspace, as there it's a lot easier to update the dataset with the latest firmware versions.

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#13 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #13 from The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) --- Ideally this should be fixed, but we are kinda stuck here:

* Piotr, do you even care about this after all this time?

* does the problem even still happen with the latest mainline kernel? might be a good idea to test this with 6.6 or 6.7-rc1 is out (e.g. in two weeks from now) before doing anything else.

* The regression was never bisected, hence it's unclear which developers is resposible for handling this (USB? IOMMU? something else?). But well, with a bit of luck Mathias commented earlier and might see this and share his thoughts.

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#14 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #14 from Piotr Piórkowski ([email protected]) --- Honestly, I had already forgotten about this problem. In the meantime, I changed the HW. Lately I have little time, but I have somewhere this HW still and if there is a need I can verify something

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#15 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #15 from The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) --- (In reply to Piotr Piórkowski from comment #14)

Quoted 1 line

Honestly, I had already forgotten about this problem.

Happens, no worries :-D

Quoted 2 lines

Lately I have little time, but I have somewhere this HW still and if there is a need I can verify something

I suggest you wait for Mathias to speak up first, I guess he should know best what's the best way forward here.

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#16 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #16 from Chris Bainbridge ([email protected]) ---

Quoted 2 lines

Pretty sure that is something that should be done in userspace, as there it's a lot easier to update the dataset with the latest firmware versions.

True, but then you have the problem of convincing distributions to ship it and enable it by default.

Quoted 1 line

The regression was never bisected

It's not a regression in the kernel as Piotr said in comment #7. It appeared on Debian kernels because Debian enabled IOMMU by default (but not for the GPU). This is a Debian-specific patch.

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#17 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #17 from Mathias Nyman ([email protected]) --- If I understand correctly this is caused by the VIA VL805 xHC controller with bad firmware accessing some DMA address outside the allowed range.

With IOMMU enabled the IOMMU will prevent this access, and the controller fails.

I'm speculating here, but it could be possible the controller accesses past one of the DMA ranges wile trying to read-ahead.

If we can figure out past which area, then its possible to make a driver workaround for this controller that allocates a bit larger DMA chunk for that specific purpose.

DMA memory allocated for xHC use before any USB device is connected:

- dcbaa device context base address array.
arrays of pointers to device contexts
dma_alloc_coherent(dev)

- command ring
dma_pool_zalloc(segment_pool)

- event ring
dma_pool_zalloc(segment_pool)

- event ring segment table
info about event ring, segents, size and location dma_alloc_coherent(dev)

- Scratchpad,
only touched (RW) by xHC controller, not driver. dma_alloc_coheret()

DMA memory allocated for each connected USB device.

- device contexts
dma_pool_zalloc(device_pool)

- transfer rings,
contains TRBs, metadata about transfers.
dma_pool_zalloc(segment_pool)

- stream contexts,
dma_alloc_coherent() or dma_pool_alloc(*_streams_pool)

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#18 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) changed:

What |Removed |Added
----------------------------------------------------------------------------
CC|[email protected] |

--- Comment #18 from The Linux kernel's regression tracker (Thorsten Leemhuis) ([email protected]) --- (In reply to Chris Bainbridge from comment #16)

Quoted 1 line

It's not a regression in the kernel as Piotr said in comment #7.

Ahh, sorry, missed/forgot that in all the regressions I deal with. Thx for pointing it out!

BTW, thx Mathias for nevertheless looking into this.

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#19 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

Rolf Reintjes ([email protected]) changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |[email protected]

--- Comment #19 from Rolf Reintjes ([email protected]) --- (In reply to Mathias Nyman from comment #17)

Quoted 3 lines

If we can figure out past which area, then its possible to make a driver workaround for this controller that allocates a bit larger DMA chunk for that specific purpose.

I am a debian user and opened this bug report:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1050352

In the last mail I was pointed here.

So I now offer my help because I have the hardware and can reproduce the bug.

I am not a kernel developer. But I am able to modify kernel source files and compile a custom kernel and let it run on debian, either debian stable or debian testing.

May be I could test new versions of the driver.

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#20 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

Michał Pecio ([email protected]) changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |[email protected]

--- Comment #20 from Michał Pecio ([email protected]) ---
By a complete accident I found that VL805 has a known bug where it overfetches transfer rings:
https://github.com/raspberrypi/linux/issues/4685

Rolf, there is a workaround for similar bug in Zhaoxin hardware which may solve your IOMMU faults.

Update to at least v6.6, or the latest v6.12 series if it's not a problem.

Run the following (if using a USB keyboard put it all in a script):
rmmod xhci_pci
rmmod xhci_hcd
modprobe xhci_hcd quirks=0x200000000000
modprobe xhci_pci

Verify that it worked:
dmesg |grep quirks

[122123.422469] xhci_hcd 0000:08:00.0: hcc params 0x002841eb hci version 0x100

quirks 0x0000200000000890

            ^-- here

And see if it helps.

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#21 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #21 from Rolf Reintjes ([email protected]) --- (In reply to Michał Pecio from comment #20)

Quoted 15 lines

By a complete accident I found that VL805 has a known bug where it overfetches transfer rings:
https://github.com/raspberrypi/linux/issues/4685

Rolf, there is a workaround for similar bug in Zhaoxin hardware which may solve your IOMMU faults.

Update to at least v6.6, or the latest v6.12 series if it's not a problem.

Run the following (if using a USB keyboard put it all in a script):
rmmod xhci_pci
rmmod xhci_hcd
modprobe xhci_hcd quirks=0x200000000000
modprobe xhci_pci

Quoted 7 lines

Verify that it worked:
dmesg |grep quirks

[122123.422469] xhci_hcd 0000:08:00.0: hcc params 0x002841eb hci version

0x100 quirks 0x0000200000000890

^-- here
And see if it helps.

Thank you very much.

I just tried it and it works. The USB port runs fine.

But what is actually done here?
modprobe xhci_hcd quirks=0x200000000000
A setting is given to the driver when starting, but what does this setting mean?

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#22 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #22 from Michał Pecio ([email protected]) --- That's good to hear. Just to be sure, can you confirm that without this quirk the problem still exists today, on the same machine running the same kernel?

This enables the XHCI_ZHAOXIN_TRB_FETCH quirk which allocates 8KB for each 4KB transfer ring segment and leaves the upper 4KB empty, so that DMA accesses beyond the 4KB segment end up hitting valid and harmless memory.

It wastes a few KB of memory per endpoint, and RasPI came up with a more efficient solution, but this is something already implemented here so we could try it immediately without patching.

BTW, there is speculation that the Zhaoxin bug may be caused by odd page size requirements of some controllers. If your kernel has debugfs enabled, please also post the output of:

grep PAGESIZE /sys/kernel/debug/usb/xhci/*/reg-op
lspci -nn |grep USB

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#23 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #23 from Rolf Reintjes ([email protected]) --- (In reply to Michał Pecio from comment #22)

Quoted 3 lines

That's good to hear. Just to be sure, can you confirm that without this quirk the problem still exists today, on the same machine running the same kernel?

The problem still exists today.

rolf@i7-5820K-debian-testing1:~$ uname -a
Linux i7-5820K-debian-testing1 6.12.5-amd64 #1 SMP PREEMPT_DYNAMIC Debian
6.12.5-1 (2024-12-15) x86_64 GNU/Linux
Quoted 5 lines

BTW, there is speculation that the Zhaoxin bug may be caused by odd page size requirements of some controllers. If your kernel has debugfs enabled, please also post the output of:

grep PAGESIZE /sys/kernel/debug/usb/xhci/*/reg-op

rolf@i7-5820K-debian-testing1:~$ sudo grep PAGESIZE
/sys/kernel/debug/usb/xhci/*/reg-op
grep: /sys/kernel/debug/usb/xhci/*/reg-op: Datei oder Verzeichnis nicht
gefunden

Which is translated: File or directory not found

Quoted 1 line

lspci -nn |grep USB

rolf@i7-5820K-debian-testing1:~$ lspci -nn |grep USB
00:14.0 USB controller [0c03]: Intel Corporation C610/X99 series chipset USB
xHCI Host Controller [8086:8d31] (rev 05)
00:1a.0 USB controller [0c03]: Intel Corporation C610/X99 series chipset USB
Enhanced Host Controller #2 [8086:8d2d] (rev 05)
00:1d.0 USB controller [0c03]: Intel Corporation C610/X99 series chipset USB
Enhanced Host Controller #1 [8086:8d26] (rev 05)
05:00.0 USB controller [0c03]: VIA Technologies, Inc. VL805/806 xHCI USB 3.0
Controller [1106:3483] (rev 01)
06:00.0 USB controller [0c03]: ASMedia Technology Inc. ASM1142 USB 3.1 Host
Controller [1b21:1242]
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#25 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #25 from Rolf Reintjes ([email protected]) --- (In reply to Michał Pecio from comment #24)

Quoted 2 lines

Maybe debugfs is not mounted. Try
mount -t debugfs none /sys/kernel/debug

root@i7-5820K-debian-testing1:/sys/kernel/debug/usb/xhci/0000:05:00.0# ls -l
reg-op 
-r--r--r-- 1 root root 0 23. Dez 13:10 reg-op

The file is empty.

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#26 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #26 from Michał Pecio ([email protected]) --- Honestly, I don't know what's the problem. Maybe as a last ditch effort try dynamic debug, if your kernel supports it:

echo 'func xhci_dbg_trace +p' >/proc/dynamic_debug/control rmmod xhci-pci
modprobe xhci-pci
echo 'func xhci_dbg_trace -p' >/proc/dynamic_debug/control dmesg |grep 'page size'

[  262.117753] xhci_hcd 0000:08:00.0: Supported page size register = 0x1
[  262.117755] xhci_hcd 0000:08:00.0: Supported page size of 8K
[  262.117756] xhci_hcd 0000:08:00.0: HCD page size set to 4K

BTW, don't worry about that 8K, this value is incorrectly calculated and then completely ignored.

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#27 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #27 from Rolf Reintjes ([email protected]) --- (In reply to Michał Pecio from comment #26)

Quoted 8 lines

Honestly, I don't know what's the problem. Maybe as a last ditch effort try dynamic debug, if your kernel supports it:

echo 'func xhci_dbg_trace +p' >/proc/dynamic_debug/control rmmod xhci-pci
modprobe xhci-pci
echo 'func xhci_dbg_trace -p' >/proc/dynamic_debug/control dmesg |grep 'page size'

Quoted 6 lines
[  262.117753] xhci_hcd 0000:08:00.0: Supported page size register = 0x1
[  262.117755] xhci_hcd 0000:08:00.0: Supported page size of 8K
[  262.117756] xhci_hcd 0000:08:00.0: HCD page size set to 4K

BTW, don't worry about that 8K, this value is incorrectly calculated and then completely ignored.

rolf@i7-5820K-debian-testing1:~$ sudo dmesg |grep 'page size'
[    0.189774] HugeTLB: registered 1.00 GiB page size, pre-allocated 0 pages
[    0.189774] HugeTLB: registered 2.00 MiB page size, pre-allocated 0 pages
[  225.577885] xhci_hcd 0000:00:14.0: Supported page size register = 0x1
[  225.577887] xhci_hcd 0000:00:14.0: Supported page size of 8K
[  225.577888] xhci_hcd 0000:00:14.0: HCD page size set to 4K
[  225.584545] xhci_hcd 0000:05:00.0: Supported page size register = 0x1
[  225.584547] xhci_hcd 0000:05:00.0: Supported page size of 8K
[  225.584548] xhci_hcd 0000:05:00.0: HCD page size set to 4K
[  225.648450] xhci_hcd 0000:06:00.0: Supported page size register = 0x1
[  225.648452] xhci_hcd 0000:06:00.0: Supported page size of 8K
[  225.648453] xhci_hcd 0000:06:00.0: HCD page size set to 4K
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#28 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

Rolf Reintjes ([email protected]) changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |[email protected]

--- Comment #28 from Rolf Reintjes ([email protected]) --- (In reply to Michał Pecio from comment #26)
I have a new E-Mail-account.

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#29 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #29 from Michał Pecio ([email protected]) --- This should now be fixed by
c133ec0e5717 usb: xhci: Enable the TRB overfetch quirk on VIA VL805

which hit mainline today and is bound for stable.

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#30 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

--- Comment #30 from Rolf Reintjes ([email protected]) --- (In reply to Michał Pecio from comment #29)

Quoted 4 lines

This should now be fixed by
c133ec0e5717 usb: xhci: Enable the TRB overfetch quirk on VIA VL805

which hit mainline today and is bound for stable.

With the newest kernel from debian testing the problem is not there any more.

rolf@i7-5820K-debian-testing1:~$ uname -a
Linux i7-5820K-debian-testing1 6.12.20-amd64 #1 SMP PREEMPT_DYNAMIC
Debian 6.12.20-1 (2025-03-23) x86_64 GNU/Linux

Thank you very much.

I thought that the patch would only be there from 6.14 kernels onwards.

Can anyone confirm that the problem has gone on other systems?

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#31 lore raw

[Bug 215906] DMAR fault when connected usb hub (xhci_hcd)

In reply to [email protected]

https://bugzilla.kernel.org/show_bug.cgi?id=215906

Paul Menzel ([email protected]) changed:

What |Removed |Added
----------------------------------------------------------------------------

                 CC|                            |pmenzel+bugzilla.kernel.org
                   |                            |@molgen.mpg.de

--- Comment #31 from Paul Menzel ([email protected]) --- @Piotr, should you still have access to the hardware, it’d be great, if you confirmed that the problem has been fixed, and close the issue.

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