Re: [PATCH v3 1/2] hw/nvme: Implement shadow doorbell buffer support

[Keith Busch]

When the request times out, the kernel should be printing the command ID. What does that say? The driver thinks the 0 is invalid, so I'm just curious what value it's expecting.

On Thu, Dec 8, 2022, 8:13 PM Guenter Roeck <linux@roeck-us.net> wrote:

On Thu, Dec 08, 2022 at 10:47:42AM -0800, Guenter Roeck wrote:
> >
> > A cq head doorbell mmio is skipped... And it is not the fault of the
> > kernel. The kernel is in it's good right to skip the mmio since the cq
> > eventidx is not properly updated.
> >
> > Adding that and it boots properly on riscv. But I'm perplexed as to why
> > this didnt show up on our regularly tested platforms.
> >
> > Gonna try to get this in for 7.2!
>
> I see another problem with sparc64.
>
> [    5.261508] could not locate request for tag 0x0
> [    5.261711] nvme nvme0: invalid id 0 completed on queue 1
>
> That is seen repeatedly until the request times out. I'll test with
> your patch to see if it resolves this problem as well, and will bisect
> otherwise.
>
The second problem is unrelated to the doorbell problem.
It is first seen in qemu v7.1. I'll try to bisect.

Guenter