On Wed, May 25, 2011 at 8:57 PM, Bruno PrÃmont <bonbons@xxxxxxxxxxxxxxxxx> wrote: > On Wed, 25 May 2011 Fabio Erculiani <lxnay@xxxxxxxxxxx> wrote: >> On Wed, May 25, 2011 at 8:46 PM, Bruno PrÃmont wrote: >> > On Wed, 25 May 2011 Fabio Erculiani <lxnay@xxxxxxxxxxx> wrote: >> >> I'm not a fbdev expert. So I leave the real fix to real men ( ;-) ). >> >> It is causing deadlock during boot, so I would consider it quite critical. >> >> Users using any fb driver will get into troubles. >> >> The workaround is to boot with vga=normal. >> > >> > What is your system doing during boot? I've never seen it here but maybe >> > my boot sequence is too simple. >> >> I'm using vesafb and vga=791. It is quite simple to reproduce. >> Also see: http://bugs.gentoo.org/show_bug.cgi?id=368109 > > Looks like gentoo kernel, might be splash is related to the hang Then, if you say so, it must be the fbsplash patch for sure, I keep forgetting of that :-/ > >> > Could you tell if it deadlocks before init gets started or afterwards, >> > which fb drivers (and extra kernel patches if any) are in use. >> >> Exactly when register_framebuffer() is called, in my case, early in >> the boot phase, before init. >> >> > >> > If you have the complete backtrace of the deadlocked processes it would >> > help getting a better idea of what is affected and how (and why just the >> > framebuffer's lock is not causing trouble with earlier kernel versions). >> >> Because that code got a HUGE rewrite in the latest cycle, where >> registration_lock has been introduce. >> Just make a diff between 2.6.38 and 2.6.39. It will be easy to see >> that SO MANY lines have changed ;-) >> Anyway, since I'm out of office these days, I won't be able to send >> you the traceback this week, but since so many people have run into >> it, I guess it's fairly simple to reproduce. > > Rewrite was not so huge, and I'm not affected here (running with KMS > compiled in though and vanilla kernel). > Probably the cause is related to one of the extra patches provided by > Gentoo and subscribing to framebuffer registration notifications. > > Will have a look. Thanks a lot, let me know if I can help out next week. > > Bruno > -- Fabio Erculiani -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
