Re: [PATCH v3 08/18] nvmet-fcloop: add missing fcloop_callback_host_done

[Daniel Wagner]

On Thu, Apr 03, 2025 at 03:25:48PM +0200, Daniel Wagner wrote:
> On Wed, Apr 02, 2025 at 07:08:06PM +0200, Daniel Wagner wrote:
> > > There is NULL pointer check in fcloop_call_host_done eventually. It is
> > > in 'nvmet-fcloop: update refs on tfcp_req'. That hunk should be in this
> > > patch though.
> > 
> > Looking again with fresh eyes. Patch #3 is adding ref counting to the
> > lport. 'nvmet-fcloop: update refs on tfcp_req' (the patch before this
> > one) adds the NULL check. Nothing will crash here. Actually, I've run
> > into this crash when testing before the NULL check was there :)
> 
> After a bit more testing and a new KASAN report, it looks like yet
> another life tracking for tfcp_req/fcpreq is a bit off. The whole
> conditional free/put indicates a something is wrong IMO. Let me see if I
> can resovle this a bit cleaner.

I found the issue which caused KASAN being unhappy. There is a state
machine for the fcp request state (active/idle/completed/aborted) which
got out of sync. I didn't want to change everything at this stage just
for the sake of refactoring. The conditional frees are still there.