From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: megasas stops I/O when running kernel as dom0 under xen4.1/4.2 Date: Wed, 24 Aug 2011 13:06:21 +0100 Message-ID: <4E54E93D.7060301@citrix.com> References: <4E43E04B.8010401@leuphana.de> <20110811225119.GA3557@dumpdata.com> <4E44EE51.70802@leuphana.de> <201108151149.44053.simon.rowe@eu.citrix.com> <4E4916A3.9070106@leuphana.de> <4E4E56EE.2070801@citrix.com> <4E4E705E.3040505@leuphana.de> <4E4E79E8.3020808@citrix.com> <4E4E913C.40809@leuphana.de> <4E4E9423.8010904@citrix.com> <4E4EA725.30405@leuphana.de> <4E521BD5.2040609@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-15" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4E521BD5.2040609@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Andreas Olsowski Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 22/08/11 10:05, Andrew Cooper wrote: > On 19/08/11 19:10, Andreas Olsowski wrote: >> Am 19.08.2011 18:49, schrieb Andrew Cooper: >> >>> The only change you need to make is in megasas_probe_one() in >>> megaraid_sas_base.c >>> >>> Add a call to pci_enable_msi(pdev) immediately after the current >> call to >>> pci_set_master(pdev); >>> >>> ~Andrew >>> >> Yep, that works fine. Removed the module option as well. >> >> root@tarballerina:~# cat /proc/interrupts |grep mega >> 2236: 69010 0 0 0 0 >> 0 0 0 xen-pirq-msi megasas >> >> The same procedure that would have lead to almost instant errors has >> not brought them to appear again. >> > Good. This is what we are seeing as well. I am still awaiting a reply > from LSI on this topic. > > Unfortunately, this does point to a regression in the way Xen deals with > legacy interrupts. Out of interest, on all 3 of your boxes with the megaraid_sas cards, could you gather the io_apic information? It is the z xen debug key on the serial console (or alternatively put apic_verbosity=debug on the xen commandline and the information gets dumped into the dmesg) -- Andrew Cooper - Dom0 Kernel Engineer, Citrix XenServer T: +44 (0)1223 225 900, http://www.citrix.com