So, it's an NFS-related regression, which is consistent with the bisect results. I guess someone who knows about NFS will have to look at it... BTW, you probably want to label the bug as regression. On Sun, Apr 25, 2010 at 10:41:59PM +0200, Robert Wimmer wrote: > I've added CONFIG_KALLSYMS and CONFIG_KALLSYMS_ALL > to my .config. I've uploaded the dmesg output. Maybe it > helps a little bit: > > https://bugzilla.kernel.org/attachment.cgi?id=26138 > > - Robert > > > On 04/25/10 11:18, Michael S. Tsirkin wrote: > > On Fri, Apr 23, 2010 at 07:26:52AM +0200, Robert Wimmer wrote: > > > >>> I'm not sure why the lockup backtrace does not show function names - > >>> is the kernel stripped? > >>> > >> I'm building the kernels always with "genkernel" a Gentoo > >> helper programm for kernel building. But I've looked into > >> the log file of genkernel and there is nothing mentioned about > >> striping the kernel. There will be a future release of genkernel > >> which supports this but this is currently not the case. Since > >> I haven't stripped the kernel I would answer no. Maybe a > >> kernel option which should be enabled? > >> > >> Thanks! > >> Robert > >> > >> > > Hmm. I have these > > CONFIG_KALLSYMS=y > > CONFIG_KALLSYMS_ALL=y > > CONFIG_KALLSYMS_EXTRA_PASS=y > > # CONFIG_STRIP_ASM_SYMS is not set > > > > > > > >> > >> On 04/22/10 12:03, Michael S. Tsirkin wrote: > >> > >>> On Thu, Apr 22, 2010 at 01:31:06PM +0200, kernel wrote: > >>> > >>> > >>>> Maybe some comments to my former mail about what I've done: > >>>> I started with a fresh clone (deleted the old /usr/src/linux > >>>> of course). > >>>> > >>>> git clone > >>>> git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git linux > >>>> > >>>> Then I started bisect > >>>> > >>>> git bisect start 'v2.6.31' 'v2.6.30' > >>>> > >>>> and build the first kernel and then marked kernels which > >>>> "crashed" with "soft lockup" or "swapper page allocation failure" > >>>> as bad and the other ones as good. Before I've compiled > >>>> a new kernel I've always done a "make mrproper". I don't know > >>>> if this is needed but thought it wouldn't hurt. > >>>> > >>>> For me it was not clear that maybe I should have had stopped > >>>> testing after the first commit that came up with a "swapper > >>>> page allocation failure". It was only one commit which cased > >>>> the allocation failure. All the other commits marked as bad > >>>> came up with a soft lockup. But I thought it is important to > >>>> find the earliest commit which crashes. So should I find out > >>>> the commit with the allocation failure? > >>>> > >>>> > >>> I think you did the right thing. We'll have to > >>> figure out soft lockup thing, then if page allocation failure > >>> turns out to be a different issue, look at it. > >>> > >>> > >>> > >>>> As you requested I've now done now a > >>>> > >>>> git checkout c02d7adf8c5429727a98bad1d039bccad4c61c50 > >>>> > >>>> which ended with a soft lockup within 3 min. after starting > >>>> the VM (see > >>>> https://bugzilla.kernel.org/attachment.cgi?id=26089&action=edit) > >>>> with this kernel. > >>>> > >>>> > >>> I'm not sure why the lockup backtrace does not show function names - > >>> is the kernel stripped? > >>> > >>> > >>> > >>>> Then I've done a > >>>> > >>>> git checkout cf8d2c11cb77f129675478792122f50827e5b0ae > >>>> > >>>> compiled and restarted the VM with this kernel version > >>>> (BTW: Of course I've always used the same .config for > >>>> all kernels I've build.). cf8d2c11cb77f129675478792122f50827e5b0ae > >>>> is running fine. > >>>> > >>>> Thanks! > >>>> Robert > >>>> > >>>> > >>> Well, so the soft lockup issue seems NFS-related? > >>> Trond, commit cf8d2c11cb77f129675478792122f50827e5b0ae seems to > >>> be causing problems on some old kernels (See bisect below). Any idea why? > >>> > >>> > >>> > >>> > >>>> On Wed, 21 Apr 2010 12:42:49 +0300, "Michael S. Tsirkin" <mst@xxxxxxxxxx> > >>>> wrote: > >>>> > >>>> > >>>>> On Wed, Apr 21, 2010 at 01:23:12PM +0200, kernel wrote: > >>>>> > >>>>> > >>>>>> So after the compiler was running hot I've now the following result: > >>>>>> > >>>>>> server10:/usr/src/linux # git bisect log > >>>>>> # bad: [74fca6a42863ffacaf7ba6f1936a9f228950f657] Linux 2.6.31 > >>>>>> # good: [07a2039b8eb0af4ff464efd3dfd95de5c02648c6] Linux 2.6.30 > >>>>>> git bisect start 'v2.6.31' 'v2.6.30' > >>>>>> # good: [925d74ae717c9a12d3618eb4b36b9fb632e2cef3] V4L/DVB (11736): > >>>>>> videobuf: modify return value of VIDIOC_REQBUFS ioctl > >>>>>> git bisect good 925d74ae717c9a12d3618eb4b36b9fb632e2cef3 > >>>>>> # bad: [a380137900fca5c79e6daa9500bdb6ea5649188e] ixgbe: Fix device > >>>>>> capabilities of 82599 single speed fiber NICs. > >>>>>> git bisect bad a380137900fca5c79e6daa9500bdb6ea5649188e > >>>>>> # good: [1dbb5765acc7a6fe4bc1957c001037cc9d02ae03] Staging: android: > >>>>>> lowmemorykiller: fix up remaining checkpatch warnings > >>>>>> git bisect good 1dbb5765acc7a6fe4bc1957c001037cc9d02ae03 > >>>>>> # good: [df36b439c5fedefe013d4449cb6a50d15e2f4d70] Merge branch > >>>>>> 'for-2.6.31' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6 > >>>>>> git bisect good df36b439c5fedefe013d4449cb6a50d15e2f4d70 > >>>>>> # bad: [a800faec1b21d7133b5f0c8c6dac593b7c4e118d] Merge branch > >>>>>> 'for-linus' > >>>>>> of git://www.jni.nu/cris > >>>>>> git bisect bad a800faec1b21d7133b5f0c8c6dac593b7c4e118d > >>>>>> # good: [ac1b7c378ef26fba6694d5f118fe7fc16fee2fe2] Merge > >>>>>> git://git.infradead.org/mtd-2.6 > >>>>>> git bisect good ac1b7c378ef26fba6694d5f118fe7fc16fee2fe2 > >>>>>> # bad: [37c6dbe290c05023b47f52528e30ce51336b93eb] V4L/DVB (12091): > >>>>>> gspca_sonixj: Add light frequency control > >>>>>> git bisect bad 37c6dbe290c05023b47f52528e30ce51336b93eb > >>>>>> # bad: [687d680985b1438360a9ba470ece8b57cd205c3b] Merge > >>>>>> git://git.infradead.org/~dwmw2/iommu-2.6.31 > >>>>>> git bisect bad 687d680985b1438360a9ba470ece8b57cd205c3b > >>>>>> # bad: [1053414068bad659479e6efa62a67403b8b1ec0a] Merge branch > >>>>>> 'for-linus' > >>>>>> of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 > >>>>>> git bisect bad 1053414068bad659479e6efa62a67403b8b1ec0a > >>>>>> # good: [b01b4babbf204443b5a846a7494546501614cefc] firewire: net: fix > >>>>>> card > >>>>>> driver reloading > >>>>>> git bisect good b01b4babbf204443b5a846a7494546501614cefc > >>>>>> # bad: [c02d7adf8c5429727a98bad1d039bccad4c61c50] NFSv4: Replace > >>>>>> nfs4_path_walk() with VFS path lookup in a private namespace > >>>>>> git bisect bad c02d7adf8c5429727a98bad1d039bccad4c61c50 > >>>>>> # good: [616511d039af402670de8500d0e24495113a9cab] VFS: Uninline the > >>>>>> function put_mnt_ns() > >>>>>> git bisect good 616511d039af402670de8500d0e24495113a9cab > >>>>>> # good: [cf8d2c11cb77f129675478792122f50827e5b0ae] VFS: Add VFS helper > >>>>>> functions for setting up private namespaces > >>>>>> git bisect good cf8d2c11cb77f129675478792122f50827e5b0ae > >>>>>> > >>>>>> > >>>>>> The last "git bisect good" prints out: > >>>>>> > >>>>>> server10:/usr/src/linux # git bisect good > >>>>>> c02d7adf8c5429727a98bad1d039bccad4c61c50 is the first bad commit > >>>>>> commit c02d7adf8c5429727a98bad1d039bccad4c61c50 > >>>>>> Author: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> > >>>>>> Date: Mon Jun 22 15:09:14 2009 -0400 > >>>>>> > >>>>>> NFSv4: Replace nfs4_path_walk() with VFS path lookup in a private > >>>>>> namespace > >>>>>> > >>>>>> As noted in the previous patch, the NFSv4 client mount code > >>>>>> > >>>>>> > >>>> currently > >>>> > >>>> > >>>>>> has several limitations. If the mount path contains symlinks, or > >>>>>> referrals, or even if it just contains a '..', then the client code > >>>>>> in > >>>>>> nfs4_path_walk() will fail with an error. > >>>>>> > >>>>>> This patch replaces the nfs4_path_walk()-based lookup with a helper > >>>>>> function that sets up a private namespace to represent the > >>>>>> > >>>>>> > >>>> namespace > >>>> > >>>> > >>>>>> on the > >>>>>> server, then uses the ordinary VFS and NFS path lookup code to walk > >>>>>> down the > >>>>>> mount path in that namespace. > >>>>>> > >>>>>> Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> > >>>>>> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > >>>>>> > >>>>>> :040000 040000 97a18818f26ab9a0987f157257eb6f399c3cc1cc > >>>>>> 9ab6c712bb64f1349b5ac9f2020191abb5780ca0 M fs > >>>>>> > >>>>>> Does this help you any further? > >>>>>> > >>>>>> Thanks! > >>>>>> Robert > >>>>>> > >>>>>> > >>>>> Looks suspiciously like some error in testing. > >>>>> Could you pls retest and verify again that > >>>>> cf8d2c11cb77f129675478792122f50827e5b0ae > >>>>> is good and c02d7adf8c5429727a98bad1d039bccad4c61c50 is bad? > >>>>> > >>>>> -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html