[+ David, VT-d maintainer ] Jiang, David, can you please have a look into this issue? Thanks, Joerg On Wed, Apr 09, 2014 at 11:32:37PM -0700, Davidlohr Bueso wrote: > On Wed, 2014-04-09 at 22:03 -0600, Bjorn Helgaas wrote: > > [+cc Joerg, iommu list] > > > > On Wed, Apr 9, 2014 at 6:19 PM, Davidlohr Bueso <davidlohr@xxxxxx> wrote: > > > On Wed, 2014-04-09 at 16:50 -0700, James Bottomley wrote: > > >> On Wed, 2014-04-09 at 16:40 -0700, Davidlohr Bueso wrote: > > >> > On Wed, 2014-04-09 at 16:10 -0700, James Bottomley wrote: > > >> > > On Wed, 2014-04-09 at 16:08 -0700, James Bottomley wrote: > > >> > > > [+linux-scsi] > > >> > > > On Wed, 2014-04-09 at 15:49 -0700, Davidlohr Bueso wrote: > > >> > > > > On Wed, 2014-04-09 at 10:39 +0800, Baoquan He wrote: > > >> > > > > > Hi, > > >> > > > > > > > >> > > > > > The kernel is 3.14.0+ which is pulled just now. > > >> > > > > > > >> > > > > Cc'ing more people. > > >> > > > > > > >> > > > > While the hpsa driver appears to be involved in some way, I'm sure if > > >> > > > > this is a related issue, but as of today's pull I'm getting another > > >> > > > > problem that causes my DL980 not to come up. > > >> > > > > > > >> > > > > *Massive* amounts of: > > >> > > > > > > >> > > > > DMAR:[fault reason 02] Present bit in context entry is clear > > >> > > > > dmar: DRHD: handling fault status reg 602 > > >> > > > > dmar: DMAR:[DMA Read] Request device [02:00.0] fault addr 7f61e000 > > >> > > > > > > >> > > > > Then: > > >> > > > > > > >> > > > > hpsa 0000:03:00.0: Controller lockup detected: 0xffff0000 > > >> > > > > ... > > >> > > > > Workqueue: events hpsa_monitor_ctlr_worker [hpsa] > > >> > > > > ... > > >> > > > > > > >> > > > > Screenshot of the actual LOCKUP: > > >> > > > > http://stgolabs.net/hpsa-hard-lockup-3.14+.png > > >> > > > > > > >> > > > > While I haven't bisected, things worked fine until at least until commit > > >> > > > > 39de65aa2c3e (April 2nd). > > >> > > > > > > >> > > > > Any ideas? > > >> > > > > > >> > > > Well, it's either a DMA remapping issue or a hpsa one. Your assertion > > >> > > > that everything worked fine until 39de65aa2c3e would tend to vindicate > > >> > > > hpsa, > > >> > > > >> > Hmm here you mean DMA, right? > > >> > > >> No, it vindicates the hpsa changes ... they don't seem to be causing > > >> problems until something goes wrong with dma remapping. > > >> > > >> > > because all the hpsa changes went in before that under > > >> > > Missing crucial info: > > >> > > > > >> > > commit 1a0b6abaea78f73d9bc0a2f6df2d9e4c917cade1 > > >> > > > > >> > > > Merge: 3e75c6d b2bff6c > > >> > > > Author: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > > >> > > > Date: Tue Apr 1 18:49:04 2014 -0700 > > >> > > > > > >> > > > Merge tag 'scsi-misc' of > > >> > > > git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi > > >> > > > > > >> > > > can you revalidate that this commit works OK just to make sure? > > >> > > > >> > Ok so I don't see those DMA messages and system starts just fine. I'm > > >> > thinking perhaps something broke after the IO mmu stuff in commit > > >> > 3f583bc21977a608908b83d03ee2250426a5695c... could this be indirectly > > >> > causing the CPU stalls and just blame hpsa in the path as a side effect? > > >> > > > >> > /me goes out to try the commit. > > >> > > >> That's my guess. The DMAR messages are DMA remapping issues caused in > > >> the IOMMU. If I had to guess, I'd say the DMAR fault message is > > >> indicating the IOMMU is calling for a mapping address before it can > > >> satisfy the driver read request, which is causing the hang apparently in > > >> the hpsa driver. > > >> > > >> I've added linux-pci to the cc; I think they deal with iommu issues on > > >> x86. > > > > > > So that merge commit appears to be the culprit, I see both the DMA > > > messages and the lockup blaming hpsa... > > > > My understanding so far (please correct me if I'm wrong): > > > > 39de65aa2c3e OK ("Merge branch 'i2c/for-next'") > > 1a0b6abaea78 OK ("Merge tag 'scsi-misc'") > > 3f583bc21977 BAD ("Merge tag 'iommu-updates-v3.15'") > > Yes, specifically (finally done bisecting): > > commit 2e45528930388658603ea24d49cf52867b928d3e > Author: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx> > Date: Wed Feb 19 14:07:36 2014 +0800 > > iommu/vt-d: Unify the way to process DMAR device scope array > > Now we have a PCI bus notification based mechanism to update DMAR > device scope array, we could extend the mechanism to support boot > time initialization too, which will help to unify and simplify > the implementation. > > Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx> > Signed-off-by: Joerg Roedel <joro@xxxxxxxxxx> > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html