[Yaffs] Kernel panic in clear_inode when using yaffs as rootfs

[Andre Renaud]

I'm using yaffs as the root filesystem for a unit, and it is
experiencing repeatible crashes - always in the same place
(fs/inode.c:252, clear_inode).

This is in Linux 2.6.14, with the latest yaffs from CVS (although not
the latest MTD, just the MTD that 2.6.14 shipped with). Using yaffs2 in
yaffs1 compatibility mode (512byte NAND).

I've attached the BUG output. Anyone have any ideas? The line that the
bug reports to is:
if (inode->i_data.nrpages)
	BUG();
so inode->i_data.nrpages should be 0 when clear_inode is called - but it
isn't for some reason.

As far as I can tell this only happens when I'm using it as the rootfs.

Thanks,
Andre

kernel BUG at fs/inode.c:252!7473 characters
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c54f0000
[00000000] *pgd=a54bd031, *pte=00000000, *ppte=00000000
Internal error: Oops: 817 [#1]
Modules linked in:
CPU: 0
PC is at __bug+0x40/0x54
LR is at 0x1
pc : [<c005a61c>]    lr : [<00000001>]    Not tainted
sp : c541bec4  ip : 60000093  fp : c541bed4
r10: 00061050  r9 : c541a000  r8 : c541bf44
r7 : c550bec0  r6 : c550bec0  r5 : c592e074  r4 : 00000000
r3 : 00000000  r2 : 00000000  r1 : 00001b60  r0 : 00000001
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  Segment user
Control: 397F  Table: A54F0000  DAC: 00000015
Process vi (pid: 914, stack limit = 0xc541a194)
Stack: (0xc541bec4 to 0xc541c000)
bec0:          c550bec0 c541bee8 c541bed8 c00c2a54 c005a5e8 c05b0000
c541bf04
bee0: c541beec c010e0a4 c00c2a0c c550bec0 c010e034 c54aabb8 c541bf1c
c541bf08
bf00: c00c3908 c010e040 c550bec0 c54a9000 c541bf2c c541bf20 c00c3aec
c00c3880
bf20: c541bf40 c541bf30 c00c3b8c c00c3adc 00000000 c541bfa4 c541bf44
c00b949c
bf40: c00c3b04 c54aac40 c04741e0 74372a07 00000009 c54a9014 00000010
00000000
bf60: 00000000 c541bf70 00000000 c00a88dc 00000005 c5faad60 c0468580
c541bfa4
bf80: c541bf8c 00063610 000635d8 00062998 0000000a c0054e84 00000000
c541bfa8
bfa0: c0054d00 c00b9374 00063610 c02a8bcc 000636a0 00000048 00000000
00000041
bfc0: 00063610 000635d8 00062998 00000000 00000000 00000000 00061050
00000000
bfe0: 000607ac bee8cb9c 000226fc 40117d54 20000010 000636a0 00000000
00000000
Backtrace:

[<c005a5dc>] (__bug+0x0/0x54) from [<c00c2a54>] (clear_inode+0x54/0xc8)
 r4 = C550BEC0
[<c00c2a00>] (clear_inode+0x0/0xc8) from [<c010e0a4>]
(yaffs_delete_inode+0x70/0x84)
 r4 = C05B0000

[<c010e034>] (yaffs_delete_inode+0x0/0x84) from [<c00c3908>]
(generic_delete_inode+0x94/0x108)
 r6 = C54AABB8  r5 = C010E034  r4 = C550BEC0

[<c00c3874>] (generic_delete_inode+0x0/0x108) from [<c00c3aec>]
(generic_drop_inode+0x1c/0x28)
 r5 = C54A9000  r4 = C550BEC0

[<c00c3ad0>] (generic_drop_inode+0x0/0x28) from [<c00c3b8c>]
(iput+0x94/0xa8)
[<c00c3af8>] (iput+0x0/0xa8) from [<c00b949c>] (sys_unlink+0x134/0x180)

 r4 = 00000000
[<c00b9368>] (sys_unlink+0x0/0x180) from [<c0054d00>]
(ret_fast_syscall+0x0/0x2c)
 r8 = C0054E84  r7 = 0000000A  r6 = 00062998  r5 = 000635D8

 r4 = 00063610
Code: 1b004110 e59f0014 eb00410e e3a03000 (e5833000)
 Segmentation fault