On Mon, 2010-04-26 at 22:25 +0200, Robert Wimmer wrote: > I've tried with NFSv3 now. With v4 the error normally occur > within 5 minutes. The VM is now running for one hour and no > soft lockup so far. So I would say it can't be reproduced with > v3. Thanks! That's useful info. > > - Have you tried running with stack tracing enabled? > > > > Can you explain this a little bit more please? CONFIG_STACKTRACE=y > was already enabled. I've now enabled > > CONFIG_USER_STACKTRACE_SUPPORT=y > CONFIG_NOP_TRACER=y > CONFIG_HAVE_FTRACE_NMI_ENTER=y > CONFIG_HAVE_FUNCTION_TRACER=y > CONFIG_HAVE_FUNCTION_GRAPH_TRACER=y > CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST=y > CONFIG_HAVE_DYNAMIC_FTRACE=y > CONFIG_HAVE_FTRACE_MCOUNT_RECORD=y > CONFIG_HAVE_FTRACE_SYSCALLS=y > CONFIG_FTRACE_NMI_ENTER=y > CONFIG_CONTEXT_SWITCH_TRACER=y > CONFIG_GENERIC_TRACER=y > CONFIG_FTRACE=y > CONFIG_FUNCTION_TRACER=y > CONFIG_FUNCTION_GRAPH_TRACER=y > CONFIG_FTRACE_SYSCALLS=y > CONFIG_STACK_TRACER=y > CONFIG_KMEMTRACE=y > CONFIG_DYNAMIC_FTRACE=y > CONFIG_FTRACE_MCOUNT_RECORD=y > CONFIG_HAVE_MMIOTRACE_SUPPORT=y > > and run > > echo 1 > /proc/sys/kernel/stack_tracer_enabled > > But the output is mostly the same in dmesg/ > var/log/messages. Can you please guide me how I can > enable the stack tracing you need? 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. 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. Cheers Trond -- 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
