Re: [BUG] uas: JMS578 returns reproducibly incorrect data after host reboot

[Michal Pecio]

On Thu, 17 Sep 2026 18:02:02 +0200, djraszit wrote:
> shutdown Pi with the enclosure connected
> -> disconnect USB after shutdown
> -> boot the Pi without the enclosure
> -> wait for Linux to boot completely
> -> reconnect USB  
> 
> I repeated this three times. All three tests were GOOD

> USB_MSD_PWR_OFF_TIME=0
> 
> I do not currently reproduce the state where the enclosure enumerates
> successfully but returns incorrect data. Instead, after consecutive
> reboots I reproducibly get the "Cannot enable" failure described
> above.
> 
> After changing it back to:
> 
> USB_MSD_PWR_OFF_TIME=1000
> 
> I repeated the test twice, starting from a known GOOD state each time.
> A reboot reproducibly resulted in the enclosure enumerating normally,
> but:
> 
> Alternate GPT is invalid, using primary GPT.
> 
> and the previously tested block returned the BAD hash.

So it's a boot issue. I think it would make sense to determine whether
the problem is caused by bootloader actions or the kernel.

Is it possible to configure the bootloader to wait a few seconds before
booting the kernel and connect or disconnect the device during this
time, or to never boot the kernel at all so that the device can be
disconnected and tested on another machine?

If it's the bootloader, and things seem to be going in this direction,
then you will need to sort this out with the vendor, obviously.

> Regarding the Raspberry Pi 5 test: yes, the enclosure was connected to
> USB 3.0/SuperSpeed. The Pi 5 uses the RP1 southbridge rather than the
> VL805 used by the Pi 4. On my Pi 5 Linux exposes two xHCI controllers,
> xhci-hcd.0 and xhci-hcd.1, each with a SuperSpeed bus at 5000M.

Thanks, that's all I wanted to know. It's some other xHCI controller.

(I looked it up, it seems RP1 uses Synopsys IP).

Regards,
Michal