Hi All, I obtain this warning message mounting a 9p filesystem using overlay: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 110 at /fs/inode.c:337 inc_nlink+0x74/0x78 Modules linked in: CPU: 0 PID: 110 Comm: mount Not tainted 4.7.0-rc2 #2 Hardware name: Generic AM33XX (Flattened Device Tree) [<c010ff7c>] (unwind_backtrace) from [<c010c6dc>] (show_stack+0x20/0x24) [<c010c6dc>] (show_stack) from [<c04a9848>] (dump_stack+0x24/0x28) [<c04a9848>] (dump_stack) from [<c012d130>] (__warn+0xf4/0x10c) [<c012d130>] (__warn) from [<c012d218>] (warn_slowpath_null+0x30/0x38) [<c012d218>] (warn_slowpath_null) from [<c024f990>] (inc_nlink+0x74/0x78) [<c024f990>] (inc_nlink) from [<c0373a70>] (v9fs_vfs_mkdir_dotl+0x140/0x1dc) [<c0373a70>] (v9fs_vfs_mkdir_dotl) from [<c0240220>] (vfs_mkdir+0xc0/0x10c) [<c0240220>] (vfs_mkdir) from [<c036e3a4>] (ovl_create_real+0xc4/0x100) [<c036e3a4>] (ovl_create_real) from [<c036ccf0>] (ovl_fill_super+0x984/0x9a8) [<c036ccf0>] (ovl_fill_super) from [<c0236d00>] (mount_nodev+0x54/0xac) [<c0236d00>] (mount_nodev) from [<c036bcec>] (ovl_mount+0x24/0x28) [<c036bcec>] (ovl_mount) from [<c0237d30>] (mount_fs+0x54/0x170) [<c0237d30>] (mount_fs) from [<c0255a00>] (vfs_kern_mount+0x58/0x124) [<c0255a00>] (vfs_kern_mount) from [<c025911c>] (do_mount+0x1f0/0xd1c) [<c025911c>] (do_mount) from [<c0259f8c>] (SyS_mount+0x84/0xac) [<c0259f8c>] (SyS_mount) from [<c0108160>] (ret_fast_syscall+0x0/0x3c) ---[ end trace 87b507e269adb5b5 ]--- So executing `cat README.txt` inside the overlayed mountpoint brings me to: Unable to handle kernel NULL pointer dereference at virtual address 00000008 pgd = cdd20000 [00000008] *pgd=8dd74831, *pte=00000000, *ppte=00000000 Internal error: Oops: 17 [#1] PREEMPT ARM Modules linked in: CPU: 0 PID: 114 Comm: cat Tainted: G W 4.7.0-rc2 #2 Hardware name: Generic AM33XX (Flattened Device Tree) task: cdae9000 ti: cdd3a000 task.ti: cdd3a000 PC is at idr_get_empty_slot+0x18/0x3a4 LR is at idr_alloc+0xc0/0x11c pc : [<c04aad20>] lr : [<c04ab16c>] psr: 600b0093 sp : cdd3bc70 ip : cdd3bcb8 fp : cdd3bcb4 r10: 00000000 r9 : 00000000 r8 : 00000001 r7 : 00000000 r6 : cdd3bcc4 r5 : 200b0013 r4 : 00000000 r3 : 02000000 r2 : cdd3bcc4 r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: 8dd20019 DAC: 00000051 Process cat (pid: 114, stack limit = 0xcdd3a210) Stack: (0xcdd3bc70 to 0xcdd3c000) bc60: cfeb7494 cfeb7484 cdd3bca4 cdd3bc88 bc80: c01d6344 c0174870 cda7d6b0 00000000 200b0013 cdd3bcc4 00000000 00000000 bca0: 00000000 00000000 cdd3bcfc cdd3bcb8 c04ab16c c04aad14 00000000 cdd3bcc8 bcc0: c04c61b4 c04c6064 cdd3bcfc cdd3bcd8 c04aa22c c04c61a4 c0fabe28 00000000 bce0: 200b0013 00000000 cdd4b800 00000000 cdd3bd1c cdd3bd00 c08c195c c04ab0b8 bd00: 02000000 00000000 cdd6a2c0 cdd94c88 cdd3bd3c cdd3bd20 c08c017c c08c1914 bd20: 00000000 cdd94c8c cdd94c88 00000000 cdd3bd7c cdd3bd40 c08c04cc c08c0144 bd40: 00008000 00000000 cdd27780 cd3ddb28 cdd4b800 00000000 00000000 cdd27780 bd60: cd3ddb28 cdd4b800 00000000 00000000 cdd3bd8c cdd3bd80 c03765f4 c08c0498 bd80: cdd3bdbc cdd3bd90 c0374900 c03765d0 c045dfd8 c027a1ac 00000000 cdd27780 bda0: cdd27788 c037485c cd3ddb28 cdd9e880 cdd3bdec cdd3bdc0 c0230fa8 c0374868 bdc0: cdd9e880 cdd27780 cdd3bea8 00000000 00000000 cdd3bea8 00000000 00000000 bde0: cdd3be0c cdd3bdf0 c0232240 c0230de8 c02400e4 cdd9e880 00000000 cdd3bf5c be00: cdd3bea4 cdd3be10 c024277c c02321e0 c01155bc c01517b0 cdd3bebc cdd3be28 be20: c020a0d0 c0115560 00000000 00000000 00000000 cfeb54e0 fffffdfa cdd3a000 be40: cdd27780 00000000 00000000 00000004 cd3d9330 00000041 cdd22db8 00000000 be60: 00000002 cd3db3d0 cdd68e50 cd3da3b8 cdc7e630 b6fd1000 cdc7ea50 00000003 be80: cdd3bf5c cdd3bea8 00000001 c0108368 cdd3a000 00000000 cdd3bf4c cdd3bea8 bea0: c0244308 c0242224 cdd68e50 cd3da3b8 a4a3e205 0000000a cdd77010 c0165310 bec0: 00000000 c0f217d4 cd3db3d0 00000101 00000002 00000040 00000000 00000000 bee0: 00000000 cdd3bee8 00000003 cd88da80 cd88da94 00000000 00000400 c02543f4 bf00: cdd3bf3c cdd3bf10 c02543f4 c01517b0 00000000 00000000 cdd77000 00000000 bf20: 00000005 c0108368 ffffff9c 00000000 00000003 ffffff9c cdd77000 00000005 bf40: cdd3bf94 cdd3bf50 c02325a8 c02442a4 cdd3bf6c cdd3bf60 c0235834 00000000 bf60: cdd30000 00000004 00000100 00000001 bec37e88 bec37f72 0000000a 00000005 bf80: c0108368 cdd3a000 cdd3bfa4 cdd3bf98 c0232684 c0232498 00000000 cdd3bfa8 bfa0: c0108160 c0232664 bec37e88 bec37f72 bec37f72 00000000 000001b6 0000004d bfc0: bec37e88 bec37f72 0000000a 00000005 00093ac0 bec37f72 00093af4 00000000 bfe0: 00000000 bec37cc4 00010f1c b6ec435c 600b0010 bec37f72 8fef6861 8fef6c61 [<c04aad20>] (idr_get_empty_slot) from [<c04ab16c>] (idr_alloc+0xc0/0x11c) [<c04ab16c>] (idr_alloc) from [<c08c195c>] (p9_idpool_get+0x54/0xd8) [<c08c195c>] (p9_idpool_get) from [<c08c017c>] (p9_fid_create+0x44/0x110) [<c08c017c>] (p9_fid_create) from [<c08c04cc>] (p9_client_walk+0x40/0x228) [<c08c04cc>] (p9_client_walk) from [<c03765f4>] (v9fs_fid_clone+0x30/0x38) [<c03765f4>] (v9fs_fid_clone) from [<c0374900>] (v9fs_file_open+0xa4/0x150) [<c0374900>] (v9fs_file_open) from [<c0230fa8>] (do_dentry_open+0x1cc/0x31c) [<c0230fa8>] (do_dentry_open) from [<c0232240>] (vfs_open+0x6c/0x90) [<c0232240>] (vfs_open) from [<c024277c>] (path_openat+0x564/0x120c) [<c024277c>] (path_openat) from [<c0244308>] (do_filp_open+0x70/0xd4) [<c0244308>] (do_filp_open) from [<c02325a8>] (do_sys_open+0x11c/0x1cc) [<c02325a8>] (do_sys_open) from [<c0232684>] (SyS_open+0x2c/0x30) [<c0232684>] (SyS_open) from [<c0108160>] (ret_fast_syscall+0x0/0x3c) Code: e24cb004 e24dd01c e3a08001 e1a09000 (e5907008) ---[ end trace 87b507e269adb5b6 ]--- note: cat[114] exited with preempt_count 2 Segmentation fault Is 9p supposed to work with overlay? Thanks! Ciao, Alessio -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
