ext2 free blocks count corrupted (was Re: Linux 2.5.10-dj1)

[Petr Vandrovec <vandrove@vc.cvut.cz>]

On Sun, Apr 28, 2002 at 01:45:38PM +0200, Rudmer van Dijk wrote:
> On Saturday 27 April 2002 15:51, Dave Jones wrote:
> > On Sat, Apr 27, 2002 at 02:51:21PM +0200, Rudmer van Dijk wrote:
> >  > The system also hangs after fscking my root partition (fsck completed
> >  > without errors)
> >  > After my harddisks went to sleep I switched the system off and after
> >  > booting the kernel (2.4.19-pre7) panics (and the caps- and scroll-lock
> >  > leds are blinking) as it can not mount the root fs due to the following
> >  > errors: EXT2-fs error (device ide0(3,1)): ext2_check_descriptors: Block
> >  > bitmap for group 0 not in group (block 0)!
> >  > EXT2-fs: group descriptors corrupted!
> >
> > This is somewhat disturbing. I'll look over the VFS changes, but I'm not
> > aware of anything added specifically to my tree that could cause this,
> > so it may be either an ext2 issue in mainline, or one of the drivers.
> 
> It happens after fsck (1.27) examined the root partition (hda1) finished and 
> the bootscripts executed the next command (fsck hdc1)
> with exactly the same fsck on 2.4.19-pre7 everything is fine (after repairing 
> the damage done in 2.5.10-dj1)

I had up-2.5.8 at home few minutes ago, and I decided to build new kernel,
and copy new debian packages from transport disk (6GB IDE) to main disk
(80GB IDE, both on onboard Promise), like I do every week when I come home. 
During kernel build (on 80GB) & debian tree copy (from 6GB->80GB) I was 
rewarded with

EXT2-fs error (device ide2(33,5)): ext2_new_block: Free blocks count corrupted for block group 19
Remounting filesystem read-only

and fsck (without reboot) said:

ppc:/usr/src/linus/linux-2.5.10# fsck /
fsck 1.27 (8-Mar-2002)
e2fsck 1.27 (8-Mar-2002)
/dev/hde5 contains a file system with errors, check forced.
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Block bitmap differences:  -(655354--655355) -655357
Fix<y>? yes

Free blocks count wrong for group #19 (0, counted=3).
Fix<y>? yes


/dev/hde5: ***** FILE SYSTEM WAS MODIFIED *****
/dev/hde5: 392606/1954560 files (4.7% non-contiguous), 3463664/3905795 blocks


File copied at crash was /mirrors/debian/.../libforms0.89_0.89-12.tar.gz,
and debugfs says about this inode (note that blocks above do not
belong to that file, they probably belonged to the kernel compilation...)
(also file was copied completely (and matches original), but timestamp
was not set):

Inode: 311820   Type: regular    Mode:  0600   Flags: 0x0   Generation:
3430397368
User:     0   Group:     0   Size: 9546288
File ACL: 0    Directory ACL: 0
Links: 1   Blockcount: 18680
Fragment:  Address: 0    Number: 0    Size: 0
ctime: 0x3ccc78d7 -- Mon Apr 29 00:33:59 2002
atime: 0x3ccc7d6c -- Mon Apr 29 00:53:32 2002
mtime: 0x3ccc78d7 -- Mon Apr 29 00:33:59 2002
BLOCKS:
(0-1):633762-633763, (2-7):633779-633784, (8-11):633789-633792,
(IND):633814, (12-14):633815-633817, (15-28):633825-633838,
(29-35):633934-633940, (36-48):634025-634037, (49-58):634057-634066,
(59-66):634090-634097, (67-75):634099-634107, (76-84):634121-634129,
(85-95):634507-634517, (96-103):634633-634640, (104-112):634642-634650,
(113-115):634662-634664, (116-117):635079-635080,
(118-125):635337-635344, (126):635397, (127-137):635473-635483,
(138-142):635507-635511, (143-152):635593-635602, (153):635604,
(154-167):635625-635638, (168-175):635675-635682,
(176-184):635684-635692, (185-195):635705-635715,
(196-200):635756-635760, (201-213):635786-635798,
(214-220):636002-636008, (221-225):636031-636035,
(226-232):636118-636124, (233-242):636130-636139,
(243-255):636153-636165, (256-257):636186-636187,
(258-268):636201-636211, (269-270):636255-636256,
(271-277):636269-636275, (278-281):636313-636316,
(282-291):636349-636358, (292-298):636369-636375,
(299-305):636417-636423, (306):636485, (307-316):636505-636514,
(317-324):636530-636537, (325-331):636821-636827,
(332-342):636857-636867, (343-345):636877-636879, (346):636898,
(347-348):636920-636921, (349):636931, (350):636942, (351):636951,
(352-362):636969-636979, (363-374):637033-637044,
(375-380):637743-637748, (381-394):637857-637870, (395):638019,
(396-409):638025-638038, (410-414):638282-638286, (415):638307,
(416-428):638313-638325, (429-436):638361-638368,
(437-443):638409-638415, (444-451):638449-638456,
(452-460):638458-638466, (461-469):638468-638476,
(470-479):638492-638501, (480-487):638526-638533,
(488-500):638545-638557, (501-510):638572-638581,
(511-517):638601-638607, (518-523):638805-638810,
(524-534):639489-639499, (535-544):639593-639602,
(545-554):639604-639613, (555-564):639653-639662,
(565-573):639665-639673, (574-582):639937-639945,
(583-592):640019-640028, (593-602):640041-640050,
(603-612):640052-640061, (613-622):640075-640084,
(623-632):640133-640142, (633-642):640157-640166,
(643-644):640204-640205, (645-654):640234-640243,
(655-657):640253-640255, (658-668):640291-640301,
(669-676):640323-640330, (677-685):640355-640363,
(686-695):640365-640374, (696-703):640417-640424,
(704-712):640427-640435, (713-722):640458-640467,
(723-732):640469-640478, (733-734):640510-640511,
(735-742):640514-640521, (743-751):640523-640531,
(752-761):640555-640564, (762-771):640580-640589, (772):641341,
(773-778):641921-641926, (779-791):642393-642405,
(792-804):642410-642422, (805-815):642425-642435,
(816-826):642497-642507, (827-835):642510-642518, (836):642529,
(837):642680, (838-845):642738-642745, (846-850):643020-643024,
(851-858):643059-643066, (859-867):643068-643076,
(868-876):643078-643086, (877-886):643105-643114,
(887-895):643242-643250, (896):643297, (897-903):643305-643311,
(904-913):643314-643323,
(914-916):643335-643337, (917-928):643345-643356,
(929-933):643404-643408, (934-942):643430-643438,
(943-951):643502-643510, (952-961):643524-643533,
(962-970):643537-643545, (971-980):643548-643557,
(981-990):643570-643579, (991-1000):643581-643590,
(1001-1008):643604-643611, (1009-1017):643613-643621,
(1018-1025):643637-643644, (1026-1034):643646-643654, (1035):643666,
(DIND):643667, (IND):643668, (1036-1042):643669-643675,
(1043-1052):643677-643686, (1053-1060):643700-643707,
(1061-1069):643709-643717, (1070-1080):643739-643749,
(1081-1089):643773-643781, (1090-1099):643805-643814,
(1100-1110):643834-643844, (1111-1121):643866-643876,
(1122-1132):643890-643900, (1133):643926, (1134-1144):643946-643956,
(1145):643958, (1146-1156):644068-644078, (1157-1164):644093-644100,
(1165-1173):644102-644110, (1174-1183):644122-644131,
(1184-1193):644133-644142, (1194-1206):644170-644182,
(1207-1215):644197-644205, (1216-1222):644209-644215, (1223):644217,
(1224-1230):644447-644453, (1231-1240):644465-644474,
(1241-1250):644476-644485, (1251-1255):646748-646752,
(1256-1258):647744-647746, (1259-1260):648398-648399,
(1261-1263):648557-648559, (1264):649316, (1265-1268):649804-649807,
(1269-1270):649977-649978, (1271-1274):649999-650002, (1275):651723,
(1276):652274, (1277-1284):654547-654554, (1285-1293):654613-654621,
(1294-1303):654635-654644, (1304-1313):654661-654670,
(1314-1323):654684-654693, (1324-1333):654713-654722,
(1334-1343):654724-654733, (1344-1353):654746-654755,
(1354-1363):654769-654778, (1364-1373):654780-654789,
(1374-1383):654805-654814, (1384-1392):654851-654859,
(1393-1401):654861-654869, (1402-1411):654882-654891,
(1412-1421):654893-654902, (1422-1428):654921-654927, (1429):654929,
(1430-1431):655019-655020, (1432-1436):655060-655064,
(1437-1449):655082-655094, (1450-1458):655105-655113,
(1459-1467):655345-655353, (1468):655356, (1469-1470):655358-655359,
(1471-1601):687867-687997, (1602-1693):688036-688127,
(1694-1853):702937-703096, (1854-1856):703098-703100,
(1857-1870):703102-703115, (1871-1872):703123-703124,
(1873-1884):703126-703137, (1885-1889):703141-703145,
(1890-1917):703185-703212, (1918-1941):703215-703238,
(1942-1947):703240-703245, (1948-1978):703247-703277,
(1979-2050):703388-703459, (2051-2059):703461-703469, (IND):703470,
(2060-2210):703471-703621, (2211-2222):703624-703635,
(2223-2291):703637-703705, (2292-2294):703707-703709,
(2295-2298):703711-703714, (2299-2302):703716-703719,
(2303-2304):703722-703723, (2305-2330):703725-703750
TOTAL: 2335