Hi Bart, On Wed, Oct 26, 2016 at 11:44:51AM -0700, Bart Van Assche wrote: > The solution I prefer is to modify the SCSI scanning code such that > the scan_mutex is only held while performing the actual LUN scanning > and while ensuring that no SCSI device has been created yet for a > certain LUN number but not while the Linux device and its sysfs > attributes are created. Since that approach would require extensive > changes in the SCSI scanning code, another approach has been chosen, > namely to make self-removal asynchronous. This patch avoids that > self-removal triggers the following deadlock:
I'm not sure I like yet another asynchronity in the scsi code, but your reason is very much understandable and I agree that this is the faster way. [...] > > References: http://www.spinics.net/lists/linux-scsi/msg86551.html > Signed-off-by: Bart Van Assche <[email protected]> > Cc: Hannes Reinecke <[email protected]> > Cc: Johannes Thumshirn <[email protected]> > Cc: Sagi Grimberg <[email protected]> > Cc: <[email protected]> > --- [...] > > +static void scsi_remove_device_async(struct scsi_device *sdev) > +{ > + if (scsi_device_get(sdev) < 0) Nit: the < 0 could be dropped, scsi_device_get returns either -ENXIO or 0. But no reason to respin. Anyways, Reviewed-by: Johannes Thumshirn <[email protected]> -- Johannes Thumshirn Storage [email protected] +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
