From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH] sd: use async_probe cookie to avoid deadlocks Date: Tue, 21 Mar 2017 09:33:58 -0400 Message-ID: <1490103238.2412.17.camel@HansenPartnership.com> References: <1490098475-21884-1-git-send-email-hare@suse.de> <1490101519.2412.13.camel@HansenPartnership.com> <1490103027.2602.5.camel@sandisk.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from bedivere.hansenpartnership.com ([66.63.167.143]:37082 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757077AbdCUNee (ORCPT ); Tue, 21 Mar 2017 09:34:34 -0400 In-Reply-To: <1490103027.2602.5.camel@sandisk.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Bart Van Assche , "hare@suse.de" , "martin.petersen@oracle.com" Cc: "linux-scsi@vger.kernel.org" , "hck@suse.de" , "hare@suse.com" On Tue, 2017-03-21 at 13:30 +0000, Bart Van Assche wrote: > On Tue, 2017-03-21 at 09:05 -0400, James Bottomley wrote: > > How does this preserve ordering? It looks like you have one cookie > > per sdkp ... is there some sort of ordering guarantee I'm not > > seeing? > > Hello James, > > Since the probe order depends on the order in which __async_probe() > adds entries to the "pending" list, and since the order of the > __async_probe() calls is not changed by this patch, shouldn't the > probe order be preserved by this patch? I don't know: that's what I'm asking. I believe they complete in order for a single domain. I thought ordering isn't preserved between domains? So moving to multiple domains loses us ordering of disk appearance. James