On Fri, 2017-05-12 at 16:24 +0000, Bart Van Assche wrote: > > Hello Martin, > > Allowing races like the one this patch tries to address to exist > makes > the ALUA code harder to maintain than necessary. Have you considered > to > make alua_bus_detach() wait until ALUA work has finished by using > e.g. > cancel_work_sync() or rcu_synchronize()? > > Bart. Hello Bart, to be honest, no, I didn't consider this yet. The current kernel crashes with BUG() if an ALUA device is detached at an inopportune point in time (not just theoretically, we actually observed this). The goal of my patch was to fix this with minimum risk to introduce other problems. The addition in patch 4/4 was an attempt to address the concern you had expressed in your review of the v1 patch. I'm not opposed to try to find a better solution, but could we maybe get the fix for the BUG() (i.e. patch 3/4) applied in the first place? AFAICS it would not conflict with a solution like the one you suggested. Best regards and thanks for the review, Martin -- Dr. Martin Wilck <mwilck@xxxxxxxx>, Tel. +49 (0)911 74053 2107 SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg)
