Re: [PATCH for-10.2] file-posix: Handle suspended dm-multipath better for SG_IO

[Kevin Wolf <kwolf@redhat.com>]

Am 03.12.2025 um 18:27 hat Hanna Czenczek geschrieben:
> On 28.11.25 23:14, Kevin Wolf wrote:
> > When introducing DM_MPATH_PROBE_PATHS, we already anticipated that
> > dm-multipath devices might be suspended for a short time when the DM
> > tables are reloaded and that they return -EAGAIN in this case. The
> > behaviour promised in the comment wasn't actually implemented, though:
> > We don't get SG_IO_MAX_RETRIES in practice, because after the first
> > 1ms sleep, DM_MPATH_PROBE_PATHS is called and if that still fails with
> > -EAGAIN, we error out immediately without any retry.
> 
> How so?  `hdev_co_ioctl_sgio_retry()` is what issues `DM_MPATH_PROBE_PATHS`,
> and if it gets `-EAGAIN` it will return `true`, requesting a retry.

Oops... You're right. I somehow ended up testing the old state with a
commit that isn't exactly the same as what went into master and it
didn't have the -EAGAIN special case yet. So this is just me running and
looking at the wrong version of the code.

Unfortunately, it's too late to fix the commit message now. But then,
it's only a random comment about the previous state and doesn't really
make a difference for this patch.

Kevin