> 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@redhat.com>
>> 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@netapp.com>
>>>> 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@netapp.com>
>>>> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
>>>>
>>>> :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?
>>>
