At Fri, 29 Sep 2006 14:29:20 +0200, Karsten Wiese wrote: > > Am Freitag, 29. September 2006 12:48 schrieb Takashi Iwai: > > At Thu, 28 Sep 2006 22:28:02 +0200, > > Karsten Wiese wrote: > > > > > > Hi > > > > > > It oopses with 2.6.18-rt4 + alsa-kernel-1.0.13rc3 now. > > > I wrote before, 2.6.18-rt3 + alsa-driver-1.0.13rc3 would be ok, > > > but its not. bug showed again reliably under memory-pressure. > > > > > > Karsten > > > > > > === > > > > > > Reset file->f_op in snd_card_file_remove(). Take 2 > > > > > > > > > i think what happens here is: > > > > > > us428control runs, kernel has allocated a struct file for /dev/hwC1D0. > > > > > > usb disconnect > > > > > > snd_usb_usx2y calls snd_card_disconnect, > > > tells us428control to exit. > > > > > > snd_card_disconnect replaces /dev/hwC1D0's file->f_op > > > with a kmalloc()ed version, that would only allow releases. > > > > > > us428control starts exiting > > > > > > __fput is called with struct file for /dev/hwC1D0. > > > > > > snd_card_file_remove() is called, alsa notices struct file > > > for /dev/hwC1D0 is about to be closed. > > > with patch below, file->f_op would be set NULL now. > > > > > > snd_usb_usx2y's free()s snd_card instance and /dev/hwC1D0's > > > file->f_ops, those that would only allow releases. > > > > > > for reason I would like to know, > > > __fput is called again with struct file for /dev/hwC1D0 > > > from us428control's do_exit(). > > > __fput see's file->f_op is still set. > > > Without patch and under memory pressure, file->f_op can > > > point to anything now. > > > > > > > > > Signed-off-by: Karsten Wiese <annabellesgarden@xxxxxxxx> > > > > I guess this bug is fixed by Florin's patch below, juding from your > > explanation. Could you check it? > > > Florin's patch fixes it. > > This one for immediate consumation by mainline, mm, rt, > and the stable teams, hmm? It'll be pushed to mainline soon together with other ALSA fixes. Then I'll forward to stable, too. Takashi ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-devel
