On Mon, Jan 09, 2006 at 09:44:26AM +0000, Hugh Dickins wrote: > On Sun, 8 Jan 2006, Linus Torvalds wrote: > > > > Code like that should use "set_page_dirty()", which does the appropriate > > callbacks to the filesystem for that page. I wonder if the bug is simply > > because the ST code just sets the dirty bit without telling anybody else > > about it... > > Yes, it should be using set_page_dirty_lock(), and that is already known > about (I have patches for this and similar sg.c, but the sg.c case is > tougher and not yet finished); but entirely irrelevant to Ryan's case. > > Quite apart from the fact that he's doing backups to tape (not dirtying > the memory from this driver), you'll find that it even passes dirty 0 > when reading into the memory (another bug; whereas sg.c conversely says > it's always dirtying when it isn't). So there's no point in Ryan > fiddling with the SetPageDirty. One thing I forgot to mention was that 2.6.11.3 had the problem too when I reverted to it. I remember now that the person who made the debian bug report for this said it only happened with a 64-bit userspace - and I switched from a 32- to 64-bit userspace when I did 2.6.11 -> 2.6.14 (and I'm too lazy to switch back). To get the backups back, I just ran a recent kernel with try_direct_io=0. If there's nothing further for me to test at this time, I guess I'll go back to doing that until there's something to try. Is that OK? -ryan - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
