Created attachment 1948593 [details] xorriso commands used to create ISO file Description of problem: fdisk shows a GPT PMBR size mismatch error on a file generated by xorriso Version-Release number of selected component (if applicable): xorriso 1.5.4-5 How reproducible: generate an ISO file using attachment xorrisofile.sh Steps to Reproduce: 1. Unpack Fedora 37 ISO file 2. Repack into directory used for xorriso source 3. Use xorriso to create ISO file (see xorrisofile.sh attachment) 4. fdisk on ISO file Actual results: fdisk on ISO file shows GPT PMBR size mismatch error Expected results: no error from fdisk Additional info: if the ISO file is generated using mkisofs emulation mode, fdisk shows no error (see mkisofsfile.sh attachment)
Created attachment 1948594 [details] mkisofile emulation commands used to create ISO file
Relaying the response from upstream: I guess the difference between the native xorriso commands in xorrisofile.sh and the mkisofs options in attachment #1948594 [details] is the different default endpadding in the two command modes. You could try the following command additionally in xorrisofile.sh: -padding included From 'man xorriso': > -padding number["k"|"m"]|"included"|"appended" > Append the given number of extra bytes to the image stream. > This is a traditional remedy for a traditional bug in block > device read drivers. Needed only for CD recordings in TAO mode. > Since one can hardly predict on what media an image might end > up, xorriso adds the traditional 300k of padding by default to > all images. > For images which will never get to a CD it is safe to use > -padding 0 . > Normally padding is not written as part of the ISO image but > appended after the image end. This is -padding mode "appended". > Emulation command -as "mkisofs" and command -jigdo cause padding > to be written as part of the image. The same effect is achieved > by -padding mode "included". Additional information: fdisk will complain again after the ISO is copied onto an USB stick, because then again the size of the storage device will not match the size in the Protective MBR. Further the location of the Backup GPT will not be correct. There are partition editors which can repair this state on the USB stick to get a flawless GPT. In case further support is needed, please consider contacting https://lists.gnu.org/mailman/listinfo/bug-xorriso directly.
Unfortunately, adding -padding included does not fix the problem.
Hi, i got xorrisofile.sh to run by extracting the EFI partition and setting variable tempfile to the path of the extracted file. Input was the mount point of Fedora-Everything-netinst-x86_64-37-1.7.iso. Indeed there remain 4 blocks of not included padding. This comes from the table-of-content emulation on overwritable media, which not only installs an additional superblock but also pads the resulting image to a multiple of 64 KiB. This can be prevented by command -compliance no_emul_toc Afterwards the complaint of fdisk is gone here. Note that xorriso command -blank does not truncate the image file if it already exists. So to surely prevent any trailing stuff in the image, you should remove the image file before the xorriso run. (It seems that "-boot_image any appended_part_as=gpt" makes the table-of-content emulation unrecognizable to xorriso. I will have to investigate whether this is a bug or a feature. In any case its currently a waste of disk blocks.) Have a nice day :) Thomas
(No, i do not need info from redhat-bugzilla)
(aatempt to clear the needinfo request)
Created attachment 1973662 [details] updated xorriso commands used to create iso file
I got xorriso to work, thanks to your help. I had to add both "-padding included" and "-compliance no_emul_toc" to the commands. I also needed to remove the -blank command and delete the output file before xorriso started. I have attached the new commands, including the way I generated the tempfile.