Can't find correct configuration

Wed Sep 6 02:21:35 PDT 2023

Zhihao Cheng, please, excuse my stupidity...:-)
To utilize these 8MiB I set "-c 2047".
I thought that 248MiB/126976=2048 and -1 to be on the safe side.
But I do not see any change in the kernel log.
Should I also change the ubifs.cfg file and increase the vol_size?

On Wed, 6 Sept 2023 at 11:53, Zhihao Cheng <chengzhihao1 at huawei.com> wrote:
>
> 在 2023/9/6 16:38, Leon Pollak 写道:
> > Yes, you are right about the situation.
> > My partition for UBI is 248MiB.
> > So, the question remains - can this 8MB be utilized?
>
> Yes, it can.
>
> > Or are they already in use by UBI which sees partition size?
> >
> >
> > On Wed, 6 Sept 2023 at 10:34, Zhihao Cheng <chengzhihao1 at huawei.com> wrote:
> >>
> >> 在 2023/9/6 15:27, Leon Pollak 写道:
> >>> I work on embedded device. The rest of the NAND is used for SPL,
> >>> U-Boot, U-Boot environment and kernel.
> >>> What is left is 248MiB.
> >>> I am not sure I can use the whole space for UBI - how will the SPL/U-Boot work?
> >>
> >> Do you mean UBI and uboot are put into same flash(256M)? If so, your
> >> partitioning method is right.
> >>
> >> 8M(mtd0) - uboot
> >> 248M(mtd1) - UBI
> >>
> >> UBI won't access mtd0.
> >>
> >>
> >>>
> >>> On Wed, 6 Sept 2023 at 10:21, Zhihao Cheng <chengzhihao1 at huawei.com> wrote:
> >>>>
> >>>> 在 2023/9/6 14:57, Leon Pollak 写道:
> >>>>> Thousands of thanks, Zhihao Cheng!!!
> >>>>> It worked exactly as you wrote.
> >>>>> The only question remained is:
> >>>>> My partition size is 248MiB.
> >>>>> I thought that leaving 8MiB "spare' will be used just for these
> >>>>> reserved PEBs, but now I understand this was incorrect.
> >>>>> So, may I utilize these 8MiB back or will they still be used by UBI
> >>>>> for something?
> >>>>>
> >>>>
> >>>> I believe you have two mtd devices, 248M(mtd0 for ubi) and 8M(reserved,
> >>>> won't be accessed by UBI) now. Please don't split the 256M into two mtd
> >>>> devices if you only need 1 UBI device, just format the whole flash(256M)
> >>>> into UBI, and UBI itself will handle its reservation without user
> >>>> intervening.
> >>>>
> >>>>> On Wed, 6 Sept 2023 at 05:50, Zhihao Cheng <chengzhihao1 at huawei.com> wrote:
> >>>>>>
> >>>>>> 在 2023/9/6 10:42, Zhihao Cheng 写道:
> >>>>>>> 在 2023/9/5 22:45, Leon Pollak 写道:
> >>>>>>> Hi
> >>>>>>>> Hello, all.
> >>>>>>>> I will be very very thankful for the help to find the correct
> >>>>>>>> configuration for my NAND.
> >>>>>>>> I passed through a lot of mails in the lists and google and ChatGPT -
> >>>>>>>> no success.
> >>>>>>>> I have 256MB NAND and 248MB partition for UBIFS. I run:
> >>>>>>>> mkfs.ubifs -v -r rootfs -F -m 2048 -e 126976 -c 1981 -o ./ubifs.img
> >>>>>>>> ubinize -v -o rootfs.img -m 2048 -p 128KiB -s 512 -O 2048 ubinize.cfg
> >>>>>>>> -----
> >>>>>>>> and ubinize.cfg looks like:
> >>>>>>>> [ubifs]
> >>>>>>>> mode=ubi
> >>>>>>>> image=./ubifs.img
> >>>>>>>> vol_id=0
> >>>>>>>> vol_size=240MiB
> >>>>>>>> vol_type=dynamic
> >>>>>>>> vol_name=ubi_rootfs
> >>>>>>>> vol_alignment=1
> >>>>>>>> vol_flags=autoresize
> >>>>>>>> ------
> >>>>>>>> Kernel configuration  was with CONFIG_MTD_UBI_BEB_LIMIT=20.
> >>>>>>>> and here is the kernel log:
> >>>>>>>> [    2.695659] ubi0: attaching mtd4
> >>>>>>>> [    3.372343] ubi0: scanning is finished
> >>>>>>>> [    3.383066] ubi0 warning: ubi_eba_init: cannot reserve enough PEBs
> >>>>>>>> for bad PEB handling, reserved 4, need 40
> >>>>>>>> [    3.404320] ubi0: volume 0 ("ubi_rootfs") re-sized from 1982 to
> >>>>>>>> 1982 LEBs
> >>>>>>>> [    3.411667] ubi0: attached mtd4 (name "FS", size 248 MiB)
> >>>>>>>> [    3.417095] ubi0: PEB size: 131072 bytes (128 KiB), LEB size:
> >>>>>>>> 126976 bytes
> >>>>>>>> [    3.424006] ubi0: min./max. I/O unit sizes: 2048/2048, sub-page
> >>>>>>>> size 512
> >>>>>>>> [    3.430740] ubi0: VID header offset: 2048 (aligned 2048), data
> >>>>>>>> offset: 4096
> >>>>>>>> [    3.437734] ubi0: good PEBs: 1990, bad PEBs: 0, corrupted PEBs: 0
> >>>>>>>> [    3.443860] ubi0: user volume: 1, internal volumes: 1, max. volumes
> >>>>>>>> count: 128
> >>>>>>>> [    3.451117] ubi0: max/mean erase counter: 1/0, WL threshold: 4096,
> >>>>>>>> image sequence number: 1590570073
> >>>>>>>> [    3.460295] ubi0: available PEBs: 0, total reserved PEBs: 1990,
> >>>>>>>> PEBs reserved for bad PEB handling: 4
> >>>>>>>> [    3.469575] ubi0: background thread "ubi_bgt0d" started, PID 131
> >>>>>>>> [    4.648718] UBIFS (ubi0:0): background thread "ubifs_bgt0_0"
> >>>>>>>> started, PID 136
> >>>>>>>> [    4.676640] UBIFS (ubi0:0): start fixing up free space
> >>>>>>>> [   10.250099] UBIFS (ubi0:0): free space fixup complete
> >>>>>>>> [   10.269046] UBIFS (ubi0:0): UBIFS: mounted UBI device 0, volume 0,
> >>>>>>>> name "ubi_rootfs"
> >>>>>>>> [   10.276830] UBIFS (ubi0:0): LEB size: 126976 bytes (124 KiB),
> >>>>>>>> min./max. I/O unit sizes: 2048 bytes/2048 bytes
> >>>>>>>> [   10.286794] UBIFS (ubi0:0): FS size: 250142720 bytes (238 MiB, 1970
> >>>>>>>> LEBs), journal size 9023488 bytes (8 MiB, 72 LEBs)
> >>>>>>>> [   10.297540] UBIFS (ubi0:0): reserved for root: 0 bytes (0 KiB)
> >>>>>>>> [   10.303406] UBIFS (ubi0:0): media format: w4/r0 (latest is w5/r0),
> >>>>>>>> UUID A14D586A-32E2-45D7-A07E-BDC472FDF31D, small LPT model
> >>>>>>>>
> >>>>>>>> My question is: why does this warning about reserved 4, needed 40
> >>>>>>>> appear? How can I solve this?
> >>>>>>>>
> >>>>>>>
> >>>>>>> Solution: Modify ubinize.cfg,  vol_size=240MiB -> vol_size=235MiB
> >>>>>>>
> >>>>>>> Why does this warning about reserved 4, needed 40 appear?
> >>>>>>> The count of bad PEBs reserved by UBI is: total_pebs(nand chip) *
> >>>>>>> CONFIG_MTD_UBI_BEB_LIMIT/1024 = 2048 *  20 / 1024 = 40
> >>>>>>> When fastmap is not enabled, the count of internal PEBs reserved by UBI
> >>>>>>> is: UBI_LAYOUT_VOLUME_EBS[2] + WL_RESERVED_PEBS[1] +
> >>>>>>> EBA_RESERVED_PEBS[1] = 4
> >>>>>>>
> >>>>>>> Total PEBs for UBI is 1990(good PEBs: 1990), the max count of user
> >>>>>>> volume PEBs is 1990 - 40 - 4 = 1946
> >>>>>>>
> >>>>>>> In ubinize.cfg, vol_size=240MiB, the count of user volume PEBs is(see
> >>>>>>> ubinize.c in mtduitls): vi_size + (leb_size - 1) / leb_size
> >>>>>>> vi_size = 240M = 240 * 1024 * 1024
> >>>>>>> leb_size = 128K - 2K(ec) - 2K(vid) = 124 * 1024
> >>>>>>> result = 1982
> >>>>>>>
> >>>>>>> So there are 1990 - 1982 - 4 = 4 PEBs reserved for bad PEB handling,
> >>>>>>> which is less than 40.
> >>>>>>>
> >>>>>>> When we set  vol_size=235MiB, the count of user volume PEBs is: (235 *
> >>>>>>> 1024 * 1024 + 124 * 1024 - 1) / (124 * 1024) = 1941
> >>>>>>> 1990 - 4 - 40 = 1946, finally maybe there is message from kernel like
> >>>>>>> "("ubi_rootfs") re-sized from 1941 to 1946 LEBs".
> >>>>>>
> >>>>>> Acutally, the 'vol_size' in ubinize.cfg means the size of data on
> >>>>>> volume(exclude vid/ec), not the size of volume(include vid/ec).
> >>>>>>
> >>>>>
> >>>>> .
> >>>>>
> >>>>
> >>>
> >>> .
> >>>
> >>
> >
> > .
> >
>