Anything we can do to investigate this further? Thanks! Robert On Wed, 28 Apr 2010 00:56:01 +0200, Robert Wimmer <kernel@xxxxxxxxxxx> wrote: > I've applied the patch against the kernel which I got > from "git clone ...." resulted in a kernel 2.6.34-rc5. > > The stack trace after mounting NFS is here: > https://bugzilla.kernel.org/attachment.cgi?id=26166 > /var/log/messages after soft lockup: > https://bugzilla.kernel.org/attachment.cgi?id=26167 > > I hope that there is any usefull information in there. > > Thanks! > Robert > > On 04/27/10 01:28, Trond Myklebust wrote: >> On Tue, 2010-04-27 at 00:18 +0200, Robert Wimmer wrote: >> >>>> Sure. In addition to what you did above, please do >>>> >>>> mount -t debugfs none /sys/kernel/debug >>>> >>>> and then cat the contents of the pseudofile at >>>> >>>> /sys/kernel/debug/tracing/stack_trace >>>> >>>> Please do this more or less immediately after you've finished mounting >>>> the NFSv4 client. >>>> >>>> >>> I've uploaded the stack trace. It was generated >>> directly after mounting. Here are the stacks: >>> >>> After mounting: >>> https://bugzilla.kernel.org/attachment.cgi?id=26153 >>> After the soft lockup: >>> https://bugzilla.kernel.org/attachment.cgi?id=26154 >>> The dmesg output of the soft lockup: >>> https://bugzilla.kernel.org/attachment.cgi?id=26155 >>> >>> >>>> Does your server have the 'crossmnt' or 'nohide' flags set, or does it >>>> use the 'refer' export option anywhere? If so, then we might have to >>>> test further, since those may trigger the NFSv4 submount feature. >>>> >>>> >>> The server has the following settings: >>> rw,nohide,insecure,async,no_subtree_check,no_root_squash >>> >>> Thanks! >>> Robert >>> >>> >>> >> That second trace is more than 5.5K deep, more than half of which is >> socket overhead :-(((. >> >> The process stack does not appear to have overflowed, however that trace >> doesn't include any IRQ stack overhead. >> >> OK... So what happens if we get rid of half of that trace by forcing >> asynchronous tasks such as this to run entirely in rpciod instead of >> first trying to run in the process context? >> >> See the attachment... >> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>