#1115981 ubiformat: Floating point exception

Package:
mtd-utils
Source:
mtd-utils
Description:
Memory Technology Device Utilities
Submitter:
Tj
Date:
2026-04-27 22:45:02 UTC
Severity:
normal
#1115981#5
Date:
2025-09-22 18:00:42 UTC
From:
To:
$ sudo /usr/sbin/ubiformat /dev/mtd0 --vid-hdr-offset=512 --sub-page-size=512 --flash-image=/dev/loop0
ubiformat: mtd0 (nand), size 536870912 bytes (512.0 MiB), 4096 eraseblocks of 131072 bytes (128.0 KiB), min. I/O size 2048 bytes
libscan: scanning eraseblock 4095 -- 100 % complete
ubiformat: 4096 eraseblocks have valid erase counter, mean value is 3
Floating point exception

However, adding --verbose option the FPE does not occur.

gdb shows:

(gdb) c
Continuing.
ubiformat: mtd0 (nand), size 536870912 bytes (512.0 MiB), 4096 eraseblocks of 131072 bytes (128.0 KiB), min. I/O size 2048 bytes
libscan: scanning eraseblock 4095 -- 100 % complete
ubiformat: 4096 eraseblocks have valid erase counter, mean value is 2

Program received signal SIGFPE, Arithmetic exception.
0x0000555555556ea2 in flash_image (si=<optimized out>, ui=0x7fffffffe0b0, mtd=0x7fffffffe170, libmtd=<optimized out>) at ubi-utils/ubiformat.c:443
443                             printf("\r" PROGRAM_NAME ": flashing eraseblock %d -- %2lld %% complete  ",
(gdb) bt full
#0  0x0000555555556ea2 in flash_image (si=<optimized out>, ui=0x7fffffffe0b0, mtd=0x7fffffffe170, libmtd=<optimized out>) at ubi-utils/ubiformat.c:443
        err = <optimized out>
        new_len = <optimized out>
        buf = <error reading variable buf (value requires 131072 bytes, which is more than max-value-size)>
        ec = <optimized out>
        fd = <optimized out>
        st_size = <optimized out>
        img_ebs = <optimized out>
        eb = 0
        written_ebs = 0
        divisor = 0
        skip_data_read = 0
        fd = <optimized out>
        img_ebs = <optimized out>
        eb = <optimized out>
        written_ebs = <optimized out>
        divisor = <optimized out>
        skip_data_read = <optimized out>
        st_size = <optimized out>
        out_close = <optimized out>
        _err = <optimized out>
        _err = <optimized out>
        err = <optimized out>
        new_len = <optimized out>
        buf = <optimized out>
        ec = <optimized out>
        _err = <optimized out>
        _err = <optimized out>
        _err = <optimized out>
#1  main (argc=<optimized out>, argv=<optimized out>) at ubi-utils/ubiformat.c:909

Note the "divisor = 0"

The code:

    if (!args.quiet && !args.verbose) {
      printf("\r" PROGRAM_NAME ": flashing eraseblock %d -- %2lld %% complete  ",
             eb, (long long)(eb + 1) * 100 / divisor);

So this seems to mean --quiet or --verbose will avoid the error.
#1115981#8
Date:
2026-04-27 22:43:06 UTC
From:
To:
Can you please check whether this hits you on trixie as well?