Re: [PATCH v10 2/2] ufs: core: requeue aborted request

[Bart Van Assche <bvanassche@acm.org>]

On 10/8/24 7:17 PM, Peter Wang (王信友) wrote:
> Yes, this patch is only for MCQ mode, because only MCQ mode
> receives OCS: ABORTED, right? This patch doesn't modify
> any of the Legacy mode flows, does it?

Agreed. What I mentioned in my email is an existing bug in the legacy
flow for ufshcd_abort_all().

> Furthermore, even if there is an issue with Legacy mode, it
> should be addressed by a separate patch, not by this one, which is
> intended to resolve the MCQ mode issue. We shouldn't mix two
> different issues together, don't you agree?

Let's proceed with this patch series and let's address what I brought
up in my email separately.

With the current approach for error handling in the UFS driver, anyone
who wants to verify or modify ufshcd_try_to_abort_task() has to consider
all possible interleavings of ufshcd_try_to_abort_task() and the
completion path (ufshcd_compl_one_cqe()). That's an unnecessary burden
on UFS driver contributors. Additionally, this is error-prone. This
applies to both modes (legacy and MCQ). I know of reports of sporadic
crashes in legacy mode related to UFS error handling. I'm wondering
whether these are perhaps the result of the issue I mentioned in a
previous email. Anyway, I will look further into this myself as soon as
I have the time.

Thanks,

Bart.