Re: [RFT PATCH v2] xhci: Fix memory leak when caching protocol extended capability PSI tables

From: Jon Hunter
Date: Thu Feb 13 2020 - 08:33:54 EST



On 11/02/2020 15:01, Mathias Nyman wrote:
> xhci driver assumed that xHC controllers have at most one custom
> supported speed table (PSI) for all usb 3.x ports.
> Memory was allocated for one PSI table under the xhci hub structure.
>
> Turns out this is not the case, some controllers have a separate
> "supported protocol capability" entry with a PSI table for each port.
> This means each usb3 roothub port can in theory support different custom
> speeds.
>
> To solve this, cache all supported protocol capabilities with their PSI
> tables in an array, and add pointers to the xhci port structure so that
> every port points to its capability entry in the array.
>
> When creating the SuperSpeedPlus USB Device Capability BOS descriptor
> for the xhci USB 3.1 roothub we for now will use only data from the
> first USB 3.1 capable protocol capability entry in the array.
> This could be improved later, this patch focuses resolving
> the memory leak.
>
> Reported-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>
> Reported-by: Sajja Venkateswara Rao <VenkateswaraRao.Sajja@xxxxxxx>
> Fixes: 47189098f8be ("xhci: parse xhci protocol speed ID list for usb 3.1 usage")
> Cc: stable <stable@xxxxxxxxxxxxxxx> # v4.4+
> Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>


Since next-20200211, we have been observing a regression exiting suspend
on our Tegra124 Jetson TK1 board. Bisect is pointing to this commit and
reverting on top of -next fixes the problem.

On exiting suspend, I am seeing the following ...

[ 56.216793] tegra-xusb 70090000.usb: Firmware already loaded, Falcon state 0x20
[ 56.216834] usb usb3: root hub lost power or was reset
[ 56.216837] usb usb4: root hub lost power or was reset
[ 56.217760] tegra-xusb 70090000.usb: No ports on the roothubs?
[ 56.218257] tegra-xusb 70090000.usb: failed to resume XHCI: -12
[ 56.218299] PM: dpm_run_callback(): platform_pm_resume+0x0/0x40 returns -12
[ 56.218312] PM: Device 70090000.usb failed to resume: error -12
[ 56.334366] hub 4-0:1.0: hub_ext_port_status failed (err = -32)
[ 56.334368] hub 3-0:1.0: hub_ext_port_status failed (err = -32)

Let me know if you have any thoughts on this.

Cheers
Jon

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nvpublic