* Unaligned jffs2 dnode address - tested by nandsim
@ 2011-05-19 11:42 Michal Simek
2011-05-24 7:33 ` Michal Simek
0 siblings, 1 reply; 5+ messages in thread
From: Michal Simek @ 2011-05-19 11:42 UTC (permalink / raw)
To: linux-mtd; +Cc: dwmw2, John Williams
[-- Attachment #1: Type: text/plain, Size: 3126 bytes --]
Hi,
I have reached one problem with jffs2 fs ecc tested by nandsim on Microblaze.
I am getting the fault like this.
# md5sum /mnt/delete.png
uncorrectable error :
uncorrectable error :
uncorrectable error :
uncorrectable error :
uncorrectable error :
mtd->read(0xcda bytes from 0xc044) returned ECC error
Data CRC 3bcfd461 != calculated CRC e6038cde for node at 0000c000
uncorrectable error :
uncorrectable error :
uncorrectable error :
uncorrectable error :
uncorrectable error :
mtd->read(0xcda bytes from 0xc044) returned ECC error
Data CRC 3bcfd461 != calculated CRC e6038cde for node at 0000c000
The main problem is that there is one address with is not aligned which caused
that ecc counting uses wrong data.
I also found in nand_ecc code that there is written
"It is assumed that the buffers are aligned." which is definitely wrong for my
case. I expect that it is 4B alignment.
I generated jffs2 filesystem by the following command (mkfs.jffs2 revision 1.60)
mkfs.jffs2 -n -b -e 16KiB -t -d <folder> -o test.jffs2
test.jffs2 is also attached.
I use these command to mounted:
flash_eraseall /dev/mtd0
nandwrite -p /dev/mtd0 /var/ftp/test.jffs2
mount -t jffs2 mtd:"NAND simulator partition 0" /mnt
After enable some jffs2 debug message I have got the log.
[JFFS2 DBG] (74) jffs2_add_tn_to_tree: insert fragment 0x00-0x1000, ver 1 at
00000900
[JFFS2 DBG] (74) jffs2_lookup_tn: root c0c37df8, offset 0
[JFFS2 DBG] (74) jffs2_add_tn_to_tree: 'this' found 0x1000-0x2000 (data)
[JFFS2 DBG] (74) jffs2_add_tn_to_tree: Ponder this ver 2, 0x1000-0x1000
[JFFS2 DBG] (74) read_dnode: After adding ver 1:
[JFFS2 DBG] (74) read_dnode: c78432c0: v 1 r 0x0-0x1000 ov 0
[JFFS2 DBG] (74) read_dnode: c78432e0: v 2 r 0x1000-0x2000 ov 0
[JFFS2 DBG] (74) read_dnode: c7843300: v 3 r 0x2000-0x3000 ov 0
[JFFS2 DBG] (74) read_dnode: c7843320: v 4 r 0x3000-0x364a ov 0
[JFFS2 DBG] (74) read_dnode: c7843340: v 5 r 0x364a-0x4000 ov 0
[JFFS2 DBG] (74) read_dnode: c7843360: v 6 r 0x4000-0x5000 ov 0
[JFFS2 DBG] (74) read_dnode: c7843380: v 7 r 0x5000-0x6000 ov 0
[JFFS2 DBG] (74) read_dnode: c78433a0: v 8 r 0x6000-0x7000 ov 0
[JFFS2 DBG] (74) read_dnode: c78433c0: v 9 r 0x7000-0x7316 ov 0
You see that tn->fn->ofs which is 0x364a which is not aligned. This offset is
causing
I also tried to disable zlib compression which caused that map has changed and
it is aligned and there is no problem with ECC computing.
mkfs.jffs2 -n -b -e 16KiB -t -d <folder> -o test-nozlib.jffs2 -x zlib
Have you ever seen this fault with alignment?
I think that the problem is with test.jffs2 generation.
Is there any option to setup that everything is aligned?
Or are you aware about any workaround how to prevent this fault?
I do some testing directly on Microblaze. Generate random files and test them
and I haven't seen any problem when target read/write data from jffs2 on nand
with ecc. The problem is only with test.jffs2 generated on host I see this fault.
Thanks,
Michal
--
Michal Simek, Ing. (M.Eng)
PetaLogix - Linux Solutions for a Reconfigurable World
w: www.petalogix.com p: +61-7-30090663,+42-0-721842854 f: +61-7-30090663
[-- Attachment #2: test.jffs2 --]
[-- Type: application/octet-stream, Size: 41884 bytes --]
[-- Attachment #3: test-nozlib.jffs2 --]
[-- Type: application/octet-stream, Size: 32380 bytes --]
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Unaligned jffs2 dnode address - tested by nandsim
2011-05-19 11:42 Unaligned jffs2 dnode address - tested by nandsim Michal Simek
@ 2011-05-24 7:33 ` Michal Simek
0 siblings, 0 replies; 5+ messages in thread
From: Michal Simek @ 2011-05-24 7:33 UTC (permalink / raw)
Cc: LKML, linux-mtd, dwmw2, John Williams, Artem Bityutskiy,
Mike Frysinger, Andy Shevchenko, Thomas Chou
Hi,
Any update on this? Does someone know if jffs dnode should be aligned or not?
I have added some developers from mtd-utils.
I have also done test with the latest mtd-utils from git and there is still
unaligned address.
Any suggestions?
Thanks,
Michal
BTW: I have fixed problem with unaligned access in the kernel but I think the
problem is mainly in fs generation.
Michal Simek wrote:
> Hi,
>
> I have reached one problem with jffs2 fs ecc tested by nandsim on
> Microblaze.
>
> I am getting the fault like this.
> # md5sum /mnt/delete.png
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> mtd->read(0xcda bytes from 0xc044) returned ECC error
> Data CRC 3bcfd461 != calculated CRC e6038cde for node at 0000c000
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> mtd->read(0xcda bytes from 0xc044) returned ECC error
> Data CRC 3bcfd461 != calculated CRC e6038cde for node at 0000c000
>
>
> The main problem is that there is one address with is not aligned which
> caused that ecc counting uses wrong data.
>
> I also found in nand_ecc code that there is written
> "It is assumed that the buffers are aligned." which is definitely wrong
> for my case. I expect that it is 4B alignment.
>
> I generated jffs2 filesystem by the following command (mkfs.jffs2
> revision 1.60)
> mkfs.jffs2 -n -b -e 16KiB -t -d <folder> -o test.jffs2
>
> test.jffs2 is also attached.
>
> I use these command to mounted:
> flash_eraseall /dev/mtd0
> nandwrite -p /dev/mtd0 /var/ftp/test.jffs2
> mount -t jffs2 mtd:"NAND simulator partition 0" /mnt
>
> After enable some jffs2 debug message I have got the log.
>
> [JFFS2 DBG] (74) jffs2_add_tn_to_tree: insert fragment 0x00-0x1000, ver
> 1 at 00000900
> [JFFS2 DBG] (74) jffs2_lookup_tn: root c0c37df8, offset 0
> [JFFS2 DBG] (74) jffs2_add_tn_to_tree: 'this' found 0x1000-0x2000 (data)
> [JFFS2 DBG] (74) jffs2_add_tn_to_tree: Ponder this ver 2, 0x1000-0x1000
> [JFFS2 DBG] (74) read_dnode: After adding ver 1:
> [JFFS2 DBG] (74) read_dnode: c78432c0: v 1 r 0x0-0x1000 ov 0
> [JFFS2 DBG] (74) read_dnode: c78432e0: v 2 r 0x1000-0x2000 ov 0
> [JFFS2 DBG] (74) read_dnode: c7843300: v 3 r 0x2000-0x3000 ov 0
> [JFFS2 DBG] (74) read_dnode: c7843320: v 4 r 0x3000-0x364a ov 0
> [JFFS2 DBG] (74) read_dnode: c7843340: v 5 r 0x364a-0x4000 ov 0
> [JFFS2 DBG] (74) read_dnode: c7843360: v 6 r 0x4000-0x5000 ov 0
> [JFFS2 DBG] (74) read_dnode: c7843380: v 7 r 0x5000-0x6000 ov 0
> [JFFS2 DBG] (74) read_dnode: c78433a0: v 8 r 0x6000-0x7000 ov 0
> [JFFS2 DBG] (74) read_dnode: c78433c0: v 9 r 0x7000-0x7316 ov 0
>
>
> You see that tn->fn->ofs which is 0x364a which is not aligned. This
> offset is causing
>
> I also tried to disable zlib compression which caused that map has
> changed and it is aligned and there is no problem with ECC computing.
> mkfs.jffs2 -n -b -e 16KiB -t -d <folder> -o test-nozlib.jffs2 -x zlib
>
> Have you ever seen this fault with alignment?
> I think that the problem is with test.jffs2 generation.
> Is there any option to setup that everything is aligned?
> Or are you aware about any workaround how to prevent this fault?
>
> I do some testing directly on Microblaze. Generate random files and test
> them and I haven't seen any problem when target read/write data from
> jffs2 on nand with ecc. The problem is only with test.jffs2 generated on
> host I see this fault.
>
> Thanks,
> Michal
>
--
Michal Simek, Ing. (M.Eng)
PetaLogix - Linux Solutions for a Reconfigurable World
w: www.petalogix.com p: +61-7-30090663,+42-0-721842854 f: +61-7-30090663
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Unaligned jffs2 dnode address - tested by nandsim
@ 2011-05-24 7:33 ` Michal Simek
0 siblings, 0 replies; 5+ messages in thread
From: Michal Simek @ 2011-05-24 7:33 UTC (permalink / raw)
Cc: Artem Bityutskiy, Mike Frysinger, Andy Shevchenko, LKML,
linux-mtd, Thomas Chou, dwmw2, John Williams
Hi,
Any update on this? Does someone know if jffs dnode should be aligned or not?
I have added some developers from mtd-utils.
I have also done test with the latest mtd-utils from git and there is still
unaligned address.
Any suggestions?
Thanks,
Michal
BTW: I have fixed problem with unaligned access in the kernel but I think the
problem is mainly in fs generation.
Michal Simek wrote:
> Hi,
>
> I have reached one problem with jffs2 fs ecc tested by nandsim on
> Microblaze.
>
> I am getting the fault like this.
> # md5sum /mnt/delete.png
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> mtd->read(0xcda bytes from 0xc044) returned ECC error
> Data CRC 3bcfd461 != calculated CRC e6038cde for node at 0000c000
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> uncorrectable error :
> mtd->read(0xcda bytes from 0xc044) returned ECC error
> Data CRC 3bcfd461 != calculated CRC e6038cde for node at 0000c000
>
>
> The main problem is that there is one address with is not aligned which
> caused that ecc counting uses wrong data.
>
> I also found in nand_ecc code that there is written
> "It is assumed that the buffers are aligned." which is definitely wrong
> for my case. I expect that it is 4B alignment.
>
> I generated jffs2 filesystem by the following command (mkfs.jffs2
> revision 1.60)
> mkfs.jffs2 -n -b -e 16KiB -t -d <folder> -o test.jffs2
>
> test.jffs2 is also attached.
>
> I use these command to mounted:
> flash_eraseall /dev/mtd0
> nandwrite -p /dev/mtd0 /var/ftp/test.jffs2
> mount -t jffs2 mtd:"NAND simulator partition 0" /mnt
>
> After enable some jffs2 debug message I have got the log.
>
> [JFFS2 DBG] (74) jffs2_add_tn_to_tree: insert fragment 0x00-0x1000, ver
> 1 at 00000900
> [JFFS2 DBG] (74) jffs2_lookup_tn: root c0c37df8, offset 0
> [JFFS2 DBG] (74) jffs2_add_tn_to_tree: 'this' found 0x1000-0x2000 (data)
> [JFFS2 DBG] (74) jffs2_add_tn_to_tree: Ponder this ver 2, 0x1000-0x1000
> [JFFS2 DBG] (74) read_dnode: After adding ver 1:
> [JFFS2 DBG] (74) read_dnode: c78432c0: v 1 r 0x0-0x1000 ov 0
> [JFFS2 DBG] (74) read_dnode: c78432e0: v 2 r 0x1000-0x2000 ov 0
> [JFFS2 DBG] (74) read_dnode: c7843300: v 3 r 0x2000-0x3000 ov 0
> [JFFS2 DBG] (74) read_dnode: c7843320: v 4 r 0x3000-0x364a ov 0
> [JFFS2 DBG] (74) read_dnode: c7843340: v 5 r 0x364a-0x4000 ov 0
> [JFFS2 DBG] (74) read_dnode: c7843360: v 6 r 0x4000-0x5000 ov 0
> [JFFS2 DBG] (74) read_dnode: c7843380: v 7 r 0x5000-0x6000 ov 0
> [JFFS2 DBG] (74) read_dnode: c78433a0: v 8 r 0x6000-0x7000 ov 0
> [JFFS2 DBG] (74) read_dnode: c78433c0: v 9 r 0x7000-0x7316 ov 0
>
>
> You see that tn->fn->ofs which is 0x364a which is not aligned. This
> offset is causing
>
> I also tried to disable zlib compression which caused that map has
> changed and it is aligned and there is no problem with ECC computing.
> mkfs.jffs2 -n -b -e 16KiB -t -d <folder> -o test-nozlib.jffs2 -x zlib
>
> Have you ever seen this fault with alignment?
> I think that the problem is with test.jffs2 generation.
> Is there any option to setup that everything is aligned?
> Or are you aware about any workaround how to prevent this fault?
>
> I do some testing directly on Microblaze. Generate random files and test
> them and I haven't seen any problem when target read/write data from
> jffs2 on nand with ecc. The problem is only with test.jffs2 generated on
> host I see this fault.
>
> Thanks,
> Michal
>
--
Michal Simek, Ing. (M.Eng)
PetaLogix - Linux Solutions for a Reconfigurable World
w: www.petalogix.com p: +61-7-30090663,+42-0-721842854 f: +61-7-30090663
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Unaligned jffs2 dnode address - tested by nandsim
2011-05-24 7:33 ` Michal Simek
@ 2011-05-27 14:35 ` Milton Miller
-1 siblings, 0 replies; 5+ messages in thread
From: Milton Miller @ 2011-05-27 14:35 UTC (permalink / raw)
To: Michal Simek; +Cc: linux-kernel, linux-mtd
Michal Simek wrote:
> Michal Simek wrote:
> >
> > Hi,
> >
> > I have reached one problem with jffs2 fs ecc tested by nandsim on
> > Microblaze.
>
> Any update on this? Does someone know if jffs dnode should be aligned or not?
> I have added some developers from mtd-utils.
>
> I have also done test with the latest mtd-utils from git and
> there is still unaligned address.
>
> Any suggestions?
I vaguely remember doingn some research in this area a few years ago
looking a report on linuxppc-dev about this and the kernel's unaligned
access was dependant on the device being given a mtd point function
which means the device is directly accessible in the cpus address space.
I don't remember much beyond that and don't have time to dig. I am
just an observer with respect to linux mtd.
>
> Thanks,
> Michal
Hope this helps your research,
milton
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Unaligned jffs2 dnode address - tested by nandsim
@ 2011-05-27 14:35 ` Milton Miller
0 siblings, 0 replies; 5+ messages in thread
From: Milton Miller @ 2011-05-27 14:35 UTC (permalink / raw)
To: Michal Simek; +Cc: linux-mtd, linux-kernel
Michal Simek wrote:
> Michal Simek wrote:
> >
> > Hi,
> >
> > I have reached one problem with jffs2 fs ecc tested by nandsim on
> > Microblaze.
>
> Any update on this? Does someone know if jffs dnode should be aligned or not?
> I have added some developers from mtd-utils.
>
> I have also done test with the latest mtd-utils from git and
> there is still unaligned address.
>
> Any suggestions?
I vaguely remember doingn some research in this area a few years ago
looking a report on linuxppc-dev about this and the kernel's unaligned
access was dependant on the device being given a mtd point function
which means the device is directly accessible in the cpus address space.
I don't remember much beyond that and don't have time to dig. I am
just an observer with respect to linux mtd.
>
> Thanks,
> Michal
Hope this helps your research,
milton
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2011-05-27 14:35 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-05-19 11:42 Unaligned jffs2 dnode address - tested by nandsim Michal Simek
2011-05-24 7:33 ` Michal Simek
2011-05-24 7:33 ` Michal Simek
2011-05-27 14:35 ` Milton Miller
2011-05-27 14:35 ` Milton Miller
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