Messages in this thread | | | Date | Mon, 11 Mar 2013 21:27:02 -0400 | From | Dave Jones <> | Subject | Re: pipe_release oops. |
| |
On Fri, Mar 08, 2013 at 10:30:01AM -0800, Linus Torvalds wrote: > On Fri, Mar 8, 2013 at 6:53 AM, Dave Jones <davej@redhat.com> wrote: > > > > Yeah, that does the trick. > > I changed your other diff a little to use a goto, which reduces a level of indentation.. > > Hmm. So I've been trying to figure this out, and I really don't see > it. Every single pipe open routine *should* make sure that the inode > has an inode->i_pipe field. So if the open() has succeeded and you > have a valid file descriptor, the inode->i_pipe thing should be there. > > I must be missing something, and I wonder if the thing I'm missing is > that with OPEN_PATH we may now have open calls that don't actually > have FMODE_READ or FMODE_WRITE set at all. > > So suddenly we end up with these pipe openers that don't update the > counts, and I could imagine that really confusing us... > > So I'm wondering if you could apply this patch, and see if that > triggers. In fact, please un-apply the other changes to fs/pipe.c too, > to see if it also obviates the need for checking i_pipe for NULL. You > should get the new warning (once), but you should not get any oopses.. > > Anyway, this would explain why the actual read/write paths don't need > to check for i_pipe - if FMODE_READ/WRITE aren't set, we'll never get > that far. But the release() and the fasync functions do get called > even for non-readable and non-writable files...
finally managed to trigger this now that all the other stuff got fixed.
WARNING: at fs/pipe.c:867 pipe_rdwr_open+0xb8/0xd0() Hardware name: GA-MA78GM-S2H Pid: 23339, comm: trinity-child0 Not tainted 3.9.0-rc2+ #91 Call Trace: [<ffffffff81045115>] warn_slowpath_common+0x75/0xa0 [<ffffffff8104515a>] warn_slowpath_null+0x1a/0x20 [<ffffffff811c4208>] pipe_rdwr_open+0xb8/0xd0 [<ffffffff811b9c5b>] do_dentry_open+0x25b/0x300 [<ffffffff811c4150>] ? pipe_unlock+0x30/0x30 [<ffffffff811b9d49>] finish_open+0x49/0x60 [<ffffffff811cb119>] do_last+0x6d9/0xf10 [<ffffffff8107a722>] ? lg_local_unlock+0x42/0x70 [<ffffffff811de629>] ? mntput_no_expire+0x49/0x130 [<ffffffff811de736>] ? mntput+0x26/0x40 [<ffffffff811c5ca2>] ? path_put+0x22/0x30 [<ffffffff811cbc93>] path_openat+0x343/0x500 [<ffffffff811cc101>] do_filp_open+0x41/0xa0 [<ffffffff811bb0a4>] do_sys_open+0xf4/0x1e0 [<ffffffff811bb1d4>] sys_openat+0x14/0x20 [<ffffffff816d08c2>] system_call_fastpath+0x16/0x1b ---[ end trace 8290ea887bf97579 ]---
Dave
| |