Re: 2.6.25-rc6 regression - hang on resume

[Soeren Sonnenburg <kernel@nn7.de>]

On Sun, 2008-04-13 at 15:53 +0200, Rafael J. Wysocki wrote:
> On Sunday, 13 of April 2008, Pavel Machek wrote:
> > On Sat 2008-04-12 09:27:42, Soeren Sonnenburg wrote:
> > > On Fri, 2008-04-11 at 23:04 +0200, Pavel Machek wrote:
> > > > On Fri 2008-04-04 08:31:29, Soeren Sonnenburg wrote:
> > > > > On Fri, 2008-04-04 at 01:22 +0200, Rafael J. Wysocki wrote:
> > > > > > The following report is on the current list of known regressions
> > > > > > from 2.6.24.  Please verify if the issue is still present in the
> > > > > > mainline.
> > > > > > 
> > > > > > 
> > > > > > Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=10319
> > > > > > Subject		: 2.6.25-rc6 regression - hang on resume
> > > > > > Submitter	: Soeren Sonnenburg <kernel@nn7.de>
> > > > > > Date		: 2008-03-25 04:44 (10 days old)
> > > > > 
> > > > > Yes. The machine resumes and display stays black using s2ram -f -p
> > > > > (blindly typing reboot etc on keyboard does what is expected). However
> > > > > display comes back on 2.6.24.
> > > > 
> > > > Could you get us any debugging output from s2ram? Or maybe even strace
> > > > it in both working and broken case, and comparing them? (You may want
> > > > to disable randomization so that results are comparable).
> > > 
> > > I did on 2.6.24
> > > 
> > > strace -ff s2ram >s2ram24.trace 2>&1
> > > 
> > > and .25
> > > 
> > > ???strace -ff s2ram >s2ram25.trace 2>&1
> > > 
> > > with the .24 bringing the display back and .25 not. Files are here
> > > 
> > > http://nn7.de/debugging/s2ram24.trace.bz2
> > > ???http://nn7.de/debugging/s2ram25.trace.bz2
> > 
> > Hmm: 
> > 
> > /sys/bus/pci/devices/0000:00:1b.0/irq
> > 
> > contains 21 in one case and 22 in another... as do other
> > interrupts. Is that expected? Can you post /proc/interrupts for both
> > versions?
> > 
> > Hmm, big part of trace is:
> > 
> > vm86old(0xb7f76c8c)                     = -1 ENOSYS (Function not
> > implemented)
> > vm86old(0xb7f76c8c)                     = -1 ENOSYS (Function not
> > implemented)
> > 
> > ...I wonder why we do it so many times?
> > 
> > And here's the difference. .25 says:
> > 
> > vm86old(0xb809ac8c)                     = -1 ENOSYS (Function not
> > implemented)
> > vm86old(0xb809ac8c)                     = -1 ENOSYS (Function not
> > implemented)
> > Error: something went wrong performing real mode call
> > open("/sys/class/graphics",
> > O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY|0x80000) = -1 ENOENT (No
> > such file or directory)
> > open("/dev/tty", O_RDWR|O_LARGEFILE)    = 6
> > ioctl(6, KDGKBTYPE, 0xbfae8887)         = 0
> > 
> > ...can you perhaps add printf-s to s2ram to find out what changed?
> 
> Well, that looks suspiciously similar to
> http://bugzilla.kernel.org/show_bug.cgi?id=10155 .

OK I tried noexec=off now... same error in s2ram ... so I guess my CPU
does not support NX ...

Soeren