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DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from]; DKIM_TRACE(0.00)[suse.de:+] X-Rspamd-Action: no action X-Spam-Flag: NO X-Spam-Score: -4.51 X-Spam-Level: X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Rspamd-Queue-Id: 03AFE5BDE8 On 3/3/26 06:39, Benjamin Marzinski wrote: > On Mon, Mar 02, 2026 at 11:39:28AM +0000, John Garry wrote: >> On 02/03/2026 02:22, Benjamin Marzinski wrote: >>>> diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig >>>> index 19d0884479a24..cfab7ad1e3c2c 100644 >>>> --- a/drivers/scsi/Kconfig >>>> +++ b/drivers/scsi/Kconfig >>>> @@ -76,6 +76,16 @@ config SCSI_LIB_KUNIT_TEST >>>> If unsure say N. >>>> +config SCSI_MULTIPATH >>>> + bool "SCSI multipath support" >>> At least until this supports ALUA, it should probably be marked >>> EXPERIMENTAL, just so people trying it out aren't surprised if it >>> doesn't multipath their device in the way they expect. >> >> I think that ALUA support will be mainline acceptance criteria, and I am >> looking to add it now. >> >> BTW, Hannes suggested to not use the DH ALUA support, so that means to >> separate out the core ALUA support from the DH stuff. So you have any >> opinion on that approach? > > I would (perhaps naively) have thought that the device handlers would be > a useful abstraction for dealing with ALUA devices. But, Hannes knows > this code much better than me. like I said before, I'm no scsi expert. > The main point of the device handlers was to inject a 'start' command whenever paths needed to be switched (Like you need to do for some active/passive arrays). But that really caused quite some issues with complexity, as you easily can get into array path ping-pong on path failure with no I/O being transmitted. So for this implementation I would stick with implicit ALUA (most modern implementations have done so already anyway), and then there's no need using the device handlers. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich