BUG 802017 - ASSERT fail in xlog_get_bp on small mem machine

[pv@xxxxxxxxxxxxx (dxm@xxxxxxxxxxxx)]

View Incident: 
http://co-op.engr.sgi.com/BugWorks/code/bwxquery.cgi?search=Search&wlong=1&view_type=Bug&wi=802017

Submitter : dxm                       Submitter Domain : engr               
Assigned Engineer : nb                Assigned Domain : sgi.com             
Assigned Group : xfs-linux            Category : software                   
Customer Reported : F                 Priority : 3                          
Project : xfs-linux                   Status : open                         
Description :
I haven't seen this problem for ages on my 64Mb crash box,
but the problem is still there.

I installed XFS on my home machine last night and was very
happy with its performance (P100, 32Mb RAM, 32Gb disk) until 
I tried to cleanly remount my XFS partition and tripped an 
ASSERT in xlog_get_bp.

My home machine is very tight on memory, but I don't think
it's an unreasonable machine to try to run XFS on. Unfortunately,
the only way I can mount my XFS partition is by running
xfs_repair on it to zero the log before mounting it.

xlog_get_bp should at least fail nicely if it can't get the
memory required but preferably the log code should be able
to work around this somehow (and/or request less memory?).

XFS assertion failed: bp, file: xfs_log_recover.c, line: 153
kernel BUG at xfs_debug.c:50!

Entering kdb (current=0xc1838000, pid 1082) Panic: invalid operand
due to panic @ 0xc288ba49
eax = 0x0000001e ebx = 0x00000000 ecx = 0xc02a2eec edx = 0x00000000 
esi = 0x0000257f edi = 0x00000000 esp = 0xc18398b4 eip = 0xc288ba49 
ebp = 0xc18398c0  ss = 0x00000018  cs = 0x00000010 eflags = 0x00010246 
 ds = 0x00000018  es = 0x00000018 origeax = 0xffffffff &regs = 0xc1839880
kdb> bt
    EBP       EIP         Function(args)
0xc18398c0 0xc288ba49 [xfs]assfail+0x2d (0xc28a5000, 0xc28a4fe0, 0x99)
                               xfs .text 0xc281d060 0xc288ba1c 0xc288ba50
0xc18398d8 0xc286a08e [xfs]xlog_get_bp+0x5e (0x100, 0xc13ce000)
                               xfs .text 0xc281d060 0xc286a030 0xc286a098
0xc1839920 0xc286b278 [xfs]xlog_find_zeroed+0x16c (0xc1dcf480, 0xc1839988)
                               xfs .text 0xc281d060 0xc286b10c 0xc286b38c
0xc1839990 0xc286a7a3 [xfs]xlog_find_head+0x1f (0xc1dcf480, 0xc1839a0c)
                               xfs .text 0xc281d060 0xc286a784 0xc286ad9c
0xc18399e0 0xc286adb9 [xfs]xlog_find_tail+0x1d (0xc1dcf480, 0xc1839a0c, 
0xc1839a14, 0x0, 0x306)
                               xfs .text 0xc281d060 0xc286ad9c 0xc286b10c
0xc1839a1c 0xc286e55d [xfs]xlog_recover+0x21 (0xc1dcf480, 0x0, 0xc13ce000)
                               xfs .text 0xc281d060 0xc286e53c 0xc286e5f8
0xc1839a3c 0xc2866b7b [xfs]xfs_log_mount+0xc7 (0xc13ce000, 0x306, 0x32360, 0x0, 
0x2580)
                               xfs .text 0xc281d060 0xc2866ab4 0xc2866bb4
0xc1839b58 0xc287300a [xfs]xfs_mountfs_int+0xa76 (0xc0be4ee0, 0xc13ce000, 
0x306, 0x4)
                               xfs .text 0xc281d060 0xc2872594 0xc28734e4
0xc1839b70 0xc28734fb [xfs]xfs_mountfs+0x17 (0xc0be4ee0, 0xc13ce000, 0x306)
                               xfs .text 0xc281d060 0xc28734e4 0xc2873500
0xc1839be8 0xc287efa9 [xfs]xfs_cmountfs+0x58d (0xc0be4ee0, 0x306, 0x306, 0x0, 
0x2)
                               xfs .text 0xc281d060 0xc287ea1c 0xc287f02c
0xc1839c70 0xc287f1e9 [xfs]xfs_mount+0xe9 (0xc0be4ee0, 0xc09b06e0, 0xc1839eb4, 
0xc28ae080, 0xc0be4ee0)
                               xfs .text 0xc281d060 0xc287f100 0xc287f2d4
more> 
0xc1839c98 0xc287f2f5 [xfs]xfs_vfsmount+0x21 (0xc0be4ee0, 0xc09b06e0, 
0xc1839eb4, 0x0, 0xc28ae080)
                               xfs .text 0xc281d060 0xc287f2d4 0xc287f30c
0xc1839ec8 0xc28942f2 [xfs]linvfs_read_super+0x236 (0xc09b0400, 0x0, 0x0)
                               xfs .text 0xc281d060 0xc28940bc 0xc2894450
0xc1839ee8 0xc012f645 read_super+0x105 (0x306, 0xc17b9520, 0xc28adca8, 0x0, 0x0)
                               kernel .text 0xc0100000 0xc012f540 0xc012f69c
0xc1839f38 0xc012f83c get_sb_bdev+0x138 (0xc28adca8, 0xc124d000, 0x0, 0x0)
                               kernel .text 0xc0100000 0xc012f704 0xc012f890
0xc1839f8c 0xc013034a do_mount+0x19e (0xc124d000, 0xc0833000, 0xc1ebb000, 
0xc0ed0000, 0x0)
                               kernel .text 0xc0100000 0xc01301ac 0xc0130460
0xc1839fbc 0xc01304dc sys_mount+0x7c (0x8059a40, 0x8059a50, 0x8059a60, 
0xc0ed0000, 0x0)
                               kernel .text 0xc0100000 0xc0130460 0xc0130520
           0xc0108f08 system_call+0x34
                               kernel .text 0xc0100000 0xc0108ed4 0xc0108f0c