nvme/039 intermittent failure

nvme/039 intermittent failure

[John Garry]

I have noticed nvme/039 for passthru error logging intermittently 
failing on v7.2-rc1

For failures, passthrough kernel logs are missing sometimes.

I had not noticed this on older kernels.

I do note that the passthru error logging kernel code uses 
pr_err_ratelimited(), so this can hardly ever be a reliable test.

Is this a known issue?

Re: nvme/039 intermittent failure

[Shin'ichiro Kawasaki]

CC+ Alan,

On Jun 29, 2026 / 15:30, John Garry wrote:
> I have noticed nvme/039 for passthru error logging intermittently failing on
> v7.2-rc1
> 
> For failures, passthrough kernel logs are missing sometimes.
> 
> I had not noticed this on older kernels.

So far I do not observe the failure with v7.2-rc1 kernel.

> 
> I do note that the passthru error logging kernel code uses
> pr_err_ratelimited(), so this can hardly ever be a reliable test.
> 
> Is this a known issue?

I wasn't aware of it. Do you observe any kernel message that indicate
that the error message, like "X: Y callbacks suppressed"? If so, the
test case maybe able to check the message to see if the test result is
reliable or not.

Alan, may I ask you to share your thoughts about the comment?

Re: nvme/039 intermittent failure

[John Garry]

On 30/06/2026 02:55, Shin'ichiro Kawasaki wrote:
> CC+ Alan,
> 

- alan, who is no longer with Oracle

> On Jun 29, 2026 / 15:30, John Garry wrote:
>> I have noticed nvme/039 for passthru error logging intermittently failing on
>> v7.2-rc1
>>
>> For failures, passthrough kernel logs are missing sometimes.
>>
>> I had not noticed this on older kernels.
> 
> So far I do not observe the failure with v7.2-rc1 kernel.
> 
>>
>> I do note that the passthru error logging kernel code uses
>> pr_err_ratelimited(), so this can hardly ever be a reliable test.
>>
>> Is this a known issue?
> 
> I wasn't aware of it. Do you observe any kernel message that indicate
> that the error message, like "X: Y callbacks suppressed"?

No, but now I find that the missing log is not occurring, but I always 
get the log with the unexpected cdw10 value

> If so, the
> test case maybe able to check the message to see if the test result is
> reliable or not.
> 
> Alan, may I ask you to share your thoughts about the comment?

I'll check it further

Thanks!

Re: nvme/039 intermittent failure

[Mateusz Nowicki]

On Jun 29, 2026 / 15:30, John Garry wrote:
>I have noticed nvme/039 for passthru error logging intermittently 
>failing on v7.2-rc1
>
>For failures, passthrough kernel logs are missing sometimes.
>
>I had not noticed this on older kernels.
>
>I do note that the passthru error logging kernel code uses 
>pr_err_ratelimited(), so this can hardly ever be a reliable test.
>
>Is this a known issue?

Hard to tell without failing logs but nvme/039 is quite unstable on my setup.
I've proposed a fix: https://lore.kernel.org/linux-block/20260630101936.2371-1-mateusz.nowicki@posteo.net/T/#u

Can you give it a try?