Strange differences in compiled kernels

[Ghost Dog]

I've noticed that while most of the newer 4.x kernels run and work fine when installed, they break when put into live media. I don't know if it's related, but the kernels that work are represented in ROX-filer as a gear, and the ones that don't work show a picture of a text document.

The properties are also different, as seen here:



As you can see, the kernel on the left is of the type "x-executable executable" but the non-working on on the right is "x-ms-dos-executable DOS/Windows executable". The run action for the one on the left is "Execute file", but the run action for the non-working one is "No run action defined".

Both kernels were compiled in the same way, and work fine when installed on hard drive installs. But the one on the right (and others like it) won't boot when incorporated into a live cd.

Can anyone explain?

[rufwoof]

A while back I was experiencing weird behaviour from some vmlinuz/initrd combinations generated the exact same way. Whilst one would boot fine, another would have long delays, and one that booted quicker once would repeatedly do so, one that booted slower/failed would repeatedly boot slower/fail.

Never figured out the problem but found that the cure was to move from a ext4 to ext3. When copying/creating vmlinuz the target file system type seems to have some bearing.

Long shot, but something like that might be similar to the problems you're seeing.

[unicorn316386]

The one that says DOS exe starts with MZ if open it in Leafpad. Dos exes starts with MZ so it probably confuses Rox-filer.

[Ghost Dog]

@rufwoof Doesn't seem to be that.

@unicorn It must be confusing Puppy's init scripts too, because those kernels don't boot!

[Iguleder]

This happens because you enabled the UEFI stub (search the kernel configuration for STUB) in the 4.x kernel. This option makes the kernel image a valid UEFI application, so it has the same header as Windows executables (starts with "MZ").

Try this:

Code: Select all

head -c 2 vmlinuz

If one kernel begins with "MZ" and the other doesn't, this is probably the right explanation.

[Ghost Dog]

Ok, thanks.