On Wed, 2024-10-09 at 11:06 -0700, Bart Van Assche wrote: > > External email : Please do not click links or open attachments until > you have verified the sender or the content. > > 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. Hi Bart, Thank you for your review. I currently cannot see the issue of duplicate releases in legacy SDB mode. ufshcd_try_to_abort_task() will directly reset if it fails. It is only in the case of success that we need to consider the possibility of ufshcd_compl_one_cqe. I believe the original design flow has already taken this into account, which is why there is protection with outstanding_lock/cq_lock. Perhaps we can wait for an actual example to occur before making corrections. Even if there is an issue, I think the probability should be very low, because the flow for legacy SDB mode has been in use for several years. Thank you again for your review. Thanks Peter
