On Wed, Jun 26, 2013 at 5:32 PM, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > On Wed, Jun 26, 2013 at 05:24:46PM +0200, Thomas Petazzoni wrote: >> Dear Sedat Dilek, >> >> On Wed, 26 Jun 2013 16:50:55 +0200, Sedat Dilek wrote: >> >> > [ TO/CC char-misc folks ] >> > >> > The CULPRIT commit [1] due to my git-bisecting is: >> > >> > commit 585d98e00ba7a5e2abe65f7a1eff631cb612289b >> > "char: misc: assign file->private_data in all cases" >> > >> > After reverting it, my system boots up fine again. >> > >> > Can someone from the char-misc folks look at that? >> >> Ok. My understanding is that the misc device registered by >> fs/fuse/dev.c:fuse_dev_init() makes the assumption that >> file->private_data == NULL when a misc device is opened. But I'm not >> sure to fully understand the code flow of the FUSE filesystem. >> >> And since it doesn't provide its own implementation of the ->open() >> operation, the misc infrastructure was leaving the file->private_data >> defined to NULL before my patch. >> >> With my patch, the file->private_data gets assigned unconditionally >> (regardless of whether the misc driver provides or does not provide a >> ->open() operation) which modifies the unwritten assumption that fuse >> was making about the initial value of file->private_data. I believe the >> assumption made by fuse over the initial value of this variable is a >> bit fragile. >> >> Maybe the FUSE code needs to be slightly adjusted to not make this >> assumption? > > As the FUSE code was working properly before this change, I think this > misc core change needs to be reverted, so I'll go do that in a bit. > Good, sound reasonable. I was not aware that char-misc and fuse code is so interwoven (hope this is the right word). - Sedat - > thanks, > > greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
