Please cc me on mmotm bug reports! On Sun, 01 Nov 2009 22:47:05 +0100 Jiri Slaby <jirislaby@xxxxxxxxx> wrote: > On 11/01/2009 07:07 PM, akpm@xxxxxxxxxxxxxxxxxxxx wrote: > > The mm-of-the-moment snapshot 2009-11-01-10-01 has been uploaded to > > Hi, I got the following warning while booting an image in qemu-kvm: > > WARNING: at fs/attr.c:158 notify_change+0x2da/0x310() > Hardware name: > Modules linked in: > Pid: 1, comm: swapper Not tainted 2.6.32-rc5-mm1_64 #862 > Call Trace: > [<ffffffff81038008>] warn_slowpath_common+0x78/0xb0 > [<ffffffff8103804f>] warn_slowpath_null+0xf/0x20 > [<ffffffff810d32ba>] notify_change+0x2da/0x310 > [<ffffffff810c5b88>] ? fsnotify_create+0x48/0x60 > [<ffffffff810c6d2b>] ? vfs_mknod+0xbb/0xe0 > [<ffffffff812487b6>] devtmpfs_create_node+0x1e6/0x270 > [<ffffffff811170d0>] ? sysfs_addrm_finish+0x20/0x280 > [<ffffffff811175d6>] ? __sysfs_add_one+0x26/0xf0 > [<ffffffff81117b6c>] ? sysfs_do_create_link+0xcc/0x160 > [<ffffffff81241cf0>] device_add+0x1e0/0x5b0 > [<ffffffff8124adb1>] ? pm_runtime_init+0xa1/0xb0 > [<ffffffff81248f05>] ? device_pm_init+0x65/0x70 > [<ffffffff812420d9>] device_register+0x19/0x20 > [<ffffffff81242290>] device_create_vargs+0xf0/0x120 > [<ffffffff812422ec>] device_create+0x2c/0x30 > [<ffffffff810c0516>] ? __register_chrdev+0x86/0xf0 > [<ffffffff81245599>] ? __class_create+0x69/0xa0 > [<ffffffff814326e9>] ? mutex_lock+0x19/0x50 > [<ffffffff811d4e23>] misc_register+0x93/0x170 > [<ffffffff818994a0>] ? vga_arb_device_init+0x0/0x77 > [<ffffffff818994b3>] vga_arb_device_init+0x13/0x77 > [<ffffffff818994a0>] ? vga_arb_device_init+0x0/0x77 > [<ffffffff810001e7>] do_one_initcall+0x37/0x190 > [<ffffffff8187d6ce>] kernel_init+0x172/0x1c8 > [<ffffffff81003c7a>] child_rip+0xa/0x20 > [<ffffffff8187d55c>] ? kernel_init+0x0/0x1c8 > [<ffffffff81003c70>] ? child_rip+0x0/0x20 There's a -mm-only debug patch: http://userweb.kernel.org/~akpm/mmotm/broken-out/notify_change-callers-must-hold-i_mutex.patch --- a/fs/attr.c~notify_change-callers-must-hold-i_mutex +++ a/fs/attr.c @@ -155,6 +155,8 @@ int notify_change(struct dentry * dentry return -EPERM; } + WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex)); + now = current_fs_time(inode->i_sb); attr->ia_ctime = now; _ I forget why it was added. It looks like it's blaming the open-coded notify_change() call in devtmpfs_create_node(). -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
