| Message ID | 20140130151703.GA20594@localhost (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Jan 30, 2014 at 12:17:04PM -0300, Ezequiel Garcia wrote: > Hi Russell, Trond: > > On Thu, Jan 30, 2014 at 02:08:34PM +0000, Russell King - ARM Linux wrote: > > I just booted Linus' tip (plus a few other patches to imx-drm and imx > > code), and stumbled into this interesting scenario: > > > [..] > > > CONFIG_NFS_FS=y > > CONFIG_NFS_V2=y > > CONFIG_NFS_V3=y > > CONFIG_NFS_V3_ACL=y > > Just came across another issue, but a bit more problematic, as my > kernel (Linus' tip as well) panics, after mounting the rootfs: > > IP-Config: Complete: > device=eth0, hwaddr=00:50:43:50:1c:15, ipaddr=192.168.0.159, mask=255.255.255.0, gw=192.168.0.1 > host=develboard, domain=, nis-domain=(none) > bootserver=192.168.0.45, rootserver=192.168.0.45, rootpath= > VFS: Mounted root (nfs filesystem) on device 0:11. > devtmpfs: mounted > Freeing unused kernel memory: 136K (c0465000 - c0487000) > Unable to handle kernel NULL pointer dereference at virtual address 00000000 > pgd = c0004000 > [00000000] *pgd=00000000 > Internal error: Oops: 5 [#1] ARM > Modules linked in: > CPU: 0 PID: 1 Comm: swapper Tainted: G W 3.13.0-10094-g9b0cd30 #276 > task: ed839a40 ti: ed83a000 task.ti: ed83a000 > PC is at xattr_resolve_name+0x14/0x94 > LR is at generic_getxattr+0x2c/0x64 > pc : [<c00a7ab0>] lr : [<c00a7b5c>] psr: a0000113 > sp : ed83be5c ip : ed83be74 fp : ed10ebc0 > r10: ed83a000 r9 : ed43d980 r8 : ed81b800 > r7 : c034dad8 r6 : 00000000 r5 : c03f3dcc r4 : ed43d980 > r3 : 00000014 r2 : ed83be8c r1 : ed83be74 r0 : 00000000 > Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel > Control: 10c53c7d Table: 00004059 DAC: 00000015 > Process swapper (pid: 1, stack limit = 0xed83a238) > Stack: (0xed83be5c to 0xed83c000) > be40: ed43d980 > be60: 00000014 ed83be8c 00000000 00000000 c04bc22c c03f3dcc ed83bf14 ed43f340 > be80: ed43d980 c01115cc 00000000 00000041 c04bba6c 00000000 00000000 002040d0 > bea0: ed81bc00 ed10ebc0 ed81bc30 c01116f8 00000000 000004d0 ed8172d0 ed43d980 > bec0: 45878fd4 00000007 bfe01007 ef7f8fc0 c04bba6c ed43d6d8 c04bba6c 00000101 > bee0: 00000000 ed809fd0 ed809fc0 ed809f50 ed809f40 00000000 edb045d8 c0078bcc > bf00: ed0e5dc0 edb045d8 00000000 bf000000 ed0e5dc0 00000000 00000000 00000000 > bf20: 00000000 00000000 bf000000 ed10ebc0 ed0e5dc0 00000001 edb045d8 c04926d0 > bf40: ed83a000 c0492758 ed10ebc0 c008fc54 00000001 ed0e5dc0 00000002 c0090cec > bf60: c03ec85c ed0e5df4 00000000 ed839c00 c0487000 c04bcec0 c03e4f08 00000000 > bf80: 00000000 00000000 00000000 00000000 00000000 c00086a8 00000000 c04bcec0 > bfa0: c0344f5c c0345004 00000000 c000e398 00000000 00000000 00000000 00000000 > bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 > [<c00a7ab0>] (xattr_resolve_name) from [<00000000>] ( (null)) > Code: e1a06000 e5915000 e3550000 0a00001d (e5900000) > ---[ end trace 15c15b4afa9eff90 ]--- > swapper (1) used greatest stack depth: 5104 bytes left > Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b > > Adding a little hack, and could produce a better strack trace. > See the diff and the stack trace below: > > diff --git a/fs/xattr.c b/fs/xattr.c > index 3377dff..bd2b173 100644 > --- a/fs/xattr.c > +++ b/fs/xattr.c > @@ -740,6 +740,10 @@ xattr_resolve_name(const struct xattr_handler **handlers, const char **name) > > if (!*name) > return NULL; > + if(!handlers) { > + dump_stack(); > + panic("ouch"); > + } > > for_each_xattr_handler(handlers, handler) { > const char *n = strcmp_prefix(*name, handler->prefix); > > CPU: 0 PID: 1 Comm: swapper Tainted: G W 3.13.0-10094-g9b0cd30-dirty #279 > [<c0012f40>] (unwind_backtrace) from [<c00107b8>] (show_stack+0x10/0x14) > [<c00107b8>] (show_stack) from [<c00a8160>] (xattr_resolve_name+0x9c/0xa8) > [<c00a8160>] (xattr_resolve_name) from [<c00a8274>] (generic_getxattr+0x2c/0x64) > [<c00a8274>] (generic_getxattr) from [<c01115e0>] (get_vfs_caps_from_disk+0x4c/0xf4) > [<c01115e0>] (get_vfs_caps_from_disk) from [<c011170c>] (cap_bprm_set_creds+0x84/0x408) > [<c011170c>] (cap_bprm_set_creds) from [<c008fc54>] (prepare_binprm+0x80/0x11c) > [<c008fc54>] (prepare_binprm) from [<c0090cec>] (do_execve+0x33c/0x46c) > [<c0090cec>] (do_execve) from [<c00086a8>] (try_to_run_init_process+0x1c/0x50) > [<c00086a8>] (try_to_run_init_process) from [<c0345024>] (kernel_init+0xa8/0x110) > [<c0345024>] (kernel_init) from [<c000e398>] (ret_from_fork+0x14/0x3c) > Kernel panic - not syncing: ouch > > FWIW, here's my piece of NFS config: > > CONFIG_NFS_FS=y > CONFIG_NFS_V2=y > CONFIG_NFS_V3=y > # CONFIG_NFS_V3_ACL is not set > # CONFIG_NFS_V4 is not set > # CONFIG_NFS_SWAP is not set > CONFIG_ROOT_NFS=y > # CONFIG_NFSD is not set > CONFIG_LOCKD=y > CONFIG_LOCKD_V4=y > CONFIG_NFS_COMMON=y > CONFIG_SUNRPC=y > > > I think it's down to this: > > > > commit 013cdf1088d7235da9477a2375654921d9b9ba9f > > Author: Christoph Hellwig <hch@infradead.org> > > Date: Fri Dec 20 05:16:53 2013 -0800 > > > > nfs: use generic posix ACL infrastructure for v3 Posix ACLs > > > > This causes a small behaviour change in that we don't bother to set > > ACLs on file creation if the mode bit can express the access permissions > > fully, and thus behaving identical to local filesystems. > > > > Signed-off-by: Christoph Hellwig <hch@lst.de> > > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> > > And also here, reverting the above seem to fix the panic. Reverting this commit with NFS3 ACLs enabled also fixes the problems I reported.
diff --git a/fs/xattr.c b/fs/xattr.c index 3377dff..bd2b173 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -740,6 +740,10 @@ xattr_resolve_name(const struct xattr_handler **handlers, const char **name) if (!*name) return NULL; + if(!handlers) { + dump_stack(); + panic("ouch"); + } for_each_xattr_handler(handlers, handler) { const char *n = strcmp_prefix(*name, handler->prefix);