Re: too many warning messages from gnumach

[Samuel Thibault]

Da Zheng, le Tue 16 Mar 2010 19:51:31 +0800, a écrit :
> On 10-3-16 下午5:21, Samuel Thibault wrote:
> > Da Zheng, le Tue 16 Mar 2010 12:48:15 +0800, a écrit :
> >> I now use the gnumach from the master branch in the git repository for
> >> development. After I built and reboot my machine, I saw a few warning 
> >> messages
> >> printed on the screen: task xxxx deallocating an invalid port xx, most 
> >> probably
> >> a bug. What's worse, when I ran vim, there are too many such messages 
> >> printed on
> >> the screen and I cannot even use vim.
> > 
> > Are you using the latest libc from debian-ports? (2.10.2-6+hurd.1)
> > One important fixes got in it, and should get rid of that warning flood.
> You are right. After I upgraded libc, no warning flood any more when I use 
> vim.
> I don't know if it works for all other programs. When I login, I see such a
> message, but I don't know where I should start to look at.

At the place where the warning is :)

Get the address of the mach_port_deallocate_debug variable, set it to 1
by entering kdb and use

w theaddress 1

then trigger the warning, you'll now get kdb invoked from the context.
Then you can use trace to get the backtrace, and "show all thread/u" to
know which process the task corresponds to. Then you can use e.g. gdb to
know exactly which mach_port_deallocate() call is apparently spurious.

Samuel