regression in 6.1.yy branch: LTP test preadv03 fails

[Yann Sionneau <ysionneau@kalrayinc.com>]

Hello,

I noticed yesterday that LTP test preadv03 now fails since 6.1.64 (it 
also fails on 6.1.65).

6.6.4, 6.6.3, 6.5.0 and 6.2.0 seem to be unaffected.

I tested this on x86_64 and kvx arch (the latter is not upstream).

I can see some ext4 related commits on 6.1.64 and 6.1.65 changes, maybe 
it's related, therefore I add ext4 mailing list as CC.

I didn't run git bisect on this so far because I noticed building an 
x86_64 ubuntu kernel on my laptop was taking ages. Maybe someone is more 
used to dealing with this and can bisect this way faster than me.

How to reproduce:

```

git clone https://github.com/linux-test-project/ltp.git

cd ltp && make autotools && ./configure

make -j4

cd testcases/kernel/syscalls/preadv

sudo ./preadv03

```

On 6.1.64 x86_64 kernel for instance it gives:

```

ysionneau@KALRAY-LP238:~/dev/ltp/testcases/kernel/syscalls/preadv$ uname -a
Linux KALRAY-LP238 6.1.64-060164-generic #202311281737 SMP 
PREEMPT_DYNAMIC Tue Nov 28 18:22:03 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
ysionneau@KALRAY-LP238:~/dev/ltp/testcases/kernel/syscalls/preadv$ sudo 
./preadv03
tst_device.c:96: TINFO: Found free device 43 '/dev/loop43'
tst_test.c:1690: TINFO: LTP version: 20230929-193-g9de9ac6c1
tst_test.c:1574: TINFO: Timeout per run is 0h 00m 30s
tst_supported_fs_types.c:90: TINFO: Kernel supports ext2
tst_supported_fs_types.c:55: TINFO: mkfs.ext2 does exist
tst_supported_fs_types.c:90: TINFO: Kernel supports ext3
tst_supported_fs_types.c:55: TINFO: mkfs.ext3 does exist
tst_supported_fs_types.c:90: TINFO: Kernel supports ext4
tst_supported_fs_types.c:55: TINFO: mkfs.ext4 does exist
tst_supported_fs_types.c:90: TINFO: Kernel supports xfs
tst_supported_fs_types.c:51: TINFO: mkfs.xfs does not exist
tst_supported_fs_types.c:90: TINFO: Kernel supports btrfs
tst_supported_fs_types.c:51: TINFO: mkfs.btrfs does not exist
tst_supported_fs_types.c:90: TINFO: Kernel supports vfat
tst_supported_fs_types.c:55: TINFO: mkfs.vfat does exist
tst_supported_fs_types.c:90: TINFO: Kernel supports exfat
tst_supported_fs_types.c:51: TINFO: mkfs.exfat does not exist
tst_supported_fs_types.c:90: TINFO: Kernel supports ntfs
tst_supported_fs_types.c:55: TINFO: mkfs.ntfs does exist
tst_supported_fs_types.c:157: TINFO: Skipping tmpfs as requested by the 
test
tst_test.c:1650: TINFO: === Testing on ext2 ===
tst_test.c:1105: TINFO: Formatting /dev/loop43 with ext2 opts='' extra 
opts=''
mke2fs 1.46.5 (30-Dec-2021)
tst_test.c:1119: TINFO: Mounting /dev/loop43 to 
/tmp/LTP_pretsQ0lS/mntpoint fstyp=ext2 flags=0
preadv03.c:102: TINFO: Using block size 512
preadv03.c:77: TFAIL: Buffer wrong at 0 have 62 expected 61
preadv03.c:77: TFAIL: Buffer wrong at 0 have 62 expected 61
preadv03.c:66: TFAIL: preadv(O_DIRECT) read 0 bytes, expected 512
tst_test.c:1650: TINFO: === Testing on ext3 ===
tst_test.c:1105: TINFO: Formatting /dev/loop43 with ext3 opts='' extra 
opts=''
mke2fs 1.46.5 (30-Dec-2021)
tst_test.c:1119: TINFO: Mounting /dev/loop43 to 
/tmp/LTP_pretsQ0lS/mntpoint fstyp=ext3 flags=0
preadv03.c:102: TINFO: Using block size 512
preadv03.c:77: TFAIL: Buffer wrong at 0 have 62 expected 61
preadv03.c:77: TFAIL: Buffer wrong at 0 have 62 expected 61
preadv03.c:66: TFAIL: preadv(O_DIRECT) read 0 bytes, expected 512
tst_test.c:1650: TINFO: === Testing on ext4 ===
tst_test.c:1105: TINFO: Formatting /dev/loop43 with ext4 opts='' extra 
opts=''
mke2fs 1.46.5 (30-Dec-2021)
tst_test.c:1119: TINFO: Mounting /dev/loop43 to 
/tmp/LTP_pretsQ0lS/mntpoint fstyp=ext4 flags=0
preadv03.c:102: TINFO: Using block size 512
preadv03.c:77: TFAIL: Buffer wrong at 0 have 62 expected 61
preadv03.c:77: TFAIL: Buffer wrong at 0 have 62 expected 61
preadv03.c:66: TFAIL: preadv(O_DIRECT) read 0 bytes, expected 512
tst_test.c:1650: TINFO: === Testing on vfat ===
tst_test.c:1105: TINFO: Formatting /dev/loop43 with vfat opts='' extra 
opts=''
tst_test.c:1119: TINFO: Mounting /dev/loop43 to 
/tmp/LTP_pretsQ0lS/mntpoint fstyp=vfat flags=0
preadv03.c:102: TINFO: Using block size 512
preadv03.c:87: TPASS: preadv(O_DIRECT) read 512 bytes successfully with 
content 'a' expectedly
preadv03.c:87: TPASS: preadv(O_DIRECT) read 512 bytes successfully with 
content 'a' expectedly
preadv03.c:87: TPASS: preadv(O_DIRECT) read 512 bytes successfully with 
content 'b' expectedly
tst_test.c:1650: TINFO: === Testing on ntfs ===
tst_test.c:1105: TINFO: Formatting /dev/loop43 with ntfs opts='' extra 
opts=''
The partition start sector was not specified for /dev/loop43 and it 
could not be obtained automatically.  It has been set to 0.
The number of sectors per track was not specified for /dev/loop43 and it 
could not be obtained automatically.  It has been set to 0.
The number of heads was not specified for /dev/loop43 and it could not 
be obtained automatically.  It has been set to 0.
To boot from a device, Windows needs the 'partition start sector', the 
'sectors per track' and the 'number of heads' to be set.
Windows will not be able to boot from this device.
tst_test.c:1119: TINFO: Mounting /dev/loop43 to 
/tmp/LTP_pretsQ0lS/mntpoint fstyp=ntfs flags=0
tst_test.c:1119: TINFO: Trying FUSE...
preadv03.c:102: TINFO: Using block size 512
preadv03.c:87: TPASS: preadv(O_DIRECT) read 512 bytes successfully with 
content 'a' expectedly
preadv03.c:87: TPASS: preadv(O_DIRECT) read 512 bytes successfully with 
content 'a' expectedly
preadv03.c:87: TPASS: preadv(O_DIRECT) read 512 bytes successfully with 
content 'b' expectedly

Summary:
passed   6
failed   9
broken   0
skipped  0
warnings 0

```

Cheers,

-- 

Yann