On Mon, Apr 22, 2024 at 07:33:21PM +0200, Linux regression tracking (Thorsten Leemhuis) wrote: > 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. I've been waiting to hear back from Oliver or Takashi. A revised patch taking my comments into account would be welcome; it should be a very small change (just one or two lines of code). Alan Stern > 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 > >> > > >
