Hi, Thorsten here, the Linux kernel's regression tracker. Top-posting for once, to make this easily accessible to everyone. Is anyone still working on fixing below regression? From here it looks stalled, but I might have missed something. Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) -- Everything you wanna know about Linux kernel regression tracking: https://linux-regtracking.leemhuis.info/about/#tldr If I did something stupid, please tell me, as explained on that page. #regzbot poke On 09.04.24 16:56, Alan Stern wrote: > On Tue, Apr 09, 2024 at 03:49:01PM +0200, Oliver Neukum wrote: >> Hi, >> >> with the following device: >> >> Bus 002 Device 002: ID fb5d:0001 BHYVE HID Tablet >> Device Descriptor: >> bLength 18 >> bDescriptorType 1 >> bcdUSB 3.00 >> bDeviceClass 0 >> bDeviceSubClass 0 >> bDeviceProtocol 0 >> bMaxPacketSize0 8 > > A USB-3 device, running at SuperSpeed with its bMaxPacketSize0 set to 8 > instead of 9? Presumably this thing never received a USB certification. > Does the packaging use the USB logo? > >> idVendor 0xfb5d >> idProduct 0x0001 >> bcdDevice 0.00 >> iManufacturer 1 BHYVE >> iProduct 2 HID Tablet >> iSerial 3 01 >> bNumConfigurations 1 > > Why on earth would an HID tablet need to run at SuperSpeed? > >> Binary Object Store Descriptor: >> bLength 5 >> bDescriptorType 15 >> wTotalLength 0x000f >> bNumDeviceCaps 1 >> SuperSpeed USB Device Capability: >> bLength 10 >> bDescriptorType 16 >> bDevCapabilityType 3 >> bmAttributes 0x00 >> wSpeedsSupported 0x0008 >> Device can operate at SuperSpeed (5Gbps) >> bFunctionalitySupport 3 >> Lowest fully-functional device speed is SuperSpeed (5Gbps) >> bU1DevExitLat 10 micro seconds >> bU2DevExitLat 32 micro seconds > > A tablet not capable of running at any speed below 5 Gbps? > >> we are getting a regression on enumeration. It used to work with the >> code prior to your patch. Takashi is proposing the attached fixed. >> It looks like we are a bit too restrictive and should just try. >> >> Regards >> Oliver > >> From: Takashi Iwai <tiwai@xxxxxxx> >> Subject: [PATCH] USB: hub: Workaround for buggy max packet size with super >> speed >> Patch-mainline: Not yet, testing >> References: bsc#1220569 >> >> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> >> >> --- >> drivers/usb/core/hub.c | 13 ++++++++++--- >> 1 file changed, 10 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c >> index e38a4124f610..64193effc456 100644 >> --- a/drivers/usb/core/hub.c >> +++ b/drivers/usb/core/hub.c >> @@ -4830,7 +4830,7 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1, >> const char *driver_name; >> bool do_new_scheme; >> const bool initial = !dev_descr; >> - int maxp0; >> + int maxp0, ep0_maxp; >> struct usb_device_descriptor *buf, *descr; >> >> buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO); >> @@ -5070,7 +5070,8 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1, >> else >> i = 0; /* Invalid */ >> } >> - if (usb_endpoint_maxp(&udev->ep0.desc) == i) { >> + ep0_maxp = usb_endpoint_maxp(&udev->ep0.desc); >> + if (ep0_maxp == i) { > > This variable looks like it was left over from earlier testing. It's > not really needed. > >> ; /* Initial ep0 maxpacket guess is right */ >> } else if ((udev->speed == USB_SPEED_FULL || >> udev->speed == USB_SPEED_HIGH) && >> @@ -5082,9 +5083,15 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1, >> dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i); >> udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i); >> usb_ep0_reinit(udev); >> + } else if (udev->speed >= USB_SPEED_SUPER && initial) { >> + /* FIXME: should be more restrictive? */ >> + /* Initial guess is wrong; use the descriptor's value */ >> + dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i); >> + udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i); >> + usb_ep0_reinit(udev); > > This could be merged with the previous case fairly easily. > >> } else { >> /* Initial guess is wrong and descriptor's value is invalid */ >> - dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", maxp0); >> + dev_err(&udev->dev, "Invalid ep0 maxpacket: %d, expected %d\n", maxp0, ep0_maxp); > > This also looks like a remnant from earlier testing. > > Alan Stern > >> retval = -EMSGSIZE; >> goto fail; >> } >> -- >> 2.35.3 >> >
