From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juergen Gross Subject: Re: Hypervisor error messages after xl block-detach with linux 3.18-rc5 Date: Mon, 24 Nov 2014 10:55:24 +0100 Message-ID: <5473008C.4080604@suse.com> References: <546EFAE3.80404@suse.com> <20141121135747.GB2886@laptop.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20141121135747.GB2886@laptop.dumpdata.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Konrad Rzeszutek Wilk Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 11/21/2014 02:57 PM, Konrad Rzeszutek Wilk wrote: > On Fri, Nov 21, 2014 at 09:42:11AM +0100, Juergen Gross wrote: >> Hi, >> >> while testing my "linear p2m list" patches I saw the following >> problem (even without my patches in place): >> >> In dom0 running linux 3.18-rc5 on top of Xen 4.4.1 I modified the >> disk image of a guest by attaching it to dom0: >> >> xl block-attach 0 file:/var/lib/libvirt/images/opensuse13-1/xvda,xvda,w >> mount /dev/xvda2 /mnt >> ... >> umount /mnt >> xl block-detach 0 xvda Did some more testing: - Seems to occur only when attaching a block device to dom0, problem shows up only after doing the block-detach. - Sometimes I see only NMI watchdog messages, looking into hanging cpu state via xen debug keys I can see the cpu(s) in question are spinning in _raw_spin_lock(): __handle_mm_fault()->__pte_alloc()->pmd_lock()->_raw_spin_lock() The hanging cpus were executing some random user processes (cron, bash, xargs), cr2 contained user addresses. - Up to now I've seen the problem on a rather huge machine only (128GB, 120 cpus). I just did a quick test on my laptop and nothing bad happened. - Even on the huge machine just doing block-attach and block-detach without mounting the filesystem on the disk was harmless. Any ideas how to find the problem? Juergen >> >> Worked without any problem. After some seconds the following messages >> were issued on the console: >> >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61110 (pfn 1f3f21c) >> (XEN) mm.c:2995:d0 Error while pinning mfn 61110 >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61110 (pfn 1f3f21c) >> (XEN) mm.c:906:d0 Attempt to create linear p.t. with write perms >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61111 (pfn 1f3f21d) >> (XEN) mm.c:2995:d0 Error while pinning mfn 61111 >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61111 (pfn 1f3f21d) >> (XEN) mm.c:906:d0 Attempt to create linear p.t. with write perms >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61120 (pfn 1f3f22c) >> (XEN) mm.c:2995:d0 Error while pinning mfn 61120 >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61120 (pfn 1f3f22c) >> (XEN) mm.c:906:d0 Attempt to create linear p.t. with write perms >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61121 (pfn 1f3f22d) >> (XEN) mm.c:2995:d0 Error while pinning mfn 61121 >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61121 (pfn 1f3f22d) >> (XEN) mm.c:906:d0 Attempt to create linear p.t. with write perms >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61102 (pfn 1f3f20e) >> (XEN) mm.c:2995:d0 Error while pinning mfn 61102 >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61102 (pfn 1f3f20e) >> (XEN) mm.c:906:d0 Attempt to create linear p.t. with write perms >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61103 (pfn 1f3f20f) >> (XEN) mm.c:2995:d0 Error while pinning mfn 61103 >> (XEN) mm.c:2352:d0 Bad type (saw 7400000000000002 != exp 1000000000000000) >> for mfn 61103 (pfn 1f3f20f) >> (XEN) mm.c:906:d0 Attempt to create linear p.t. with write perms >> >> Is this a known issue? > > No. First time I see it. >> >> >> Juergen >> >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.xen.org >> http://lists.xen.org/xen-devel > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel >