pvmfw.img is an Android boot image (according to the file command). The unpack_bootimg.py from AOSP can unpack it, but the "kernel" file inside of it has just "data" as its file type.

$ file pvmfw.img.unpacked/* 
kernel:  data
ramdisk: empty

The pvmfw.img file itself has this type:

$ file pvmfw.img
pvmfw.img: Android bootimg, kernel

Yeah, not even AOSP's extract_kernel.py can make some sense out of pvmfw.img.unpacked/kernel.

Maybe I should try checking if platform/build/+/master/tools/extract_kernel.py can make some sense out of it.

Aside from this, I've also used unpack_bootimg.pyto unpack the boot.img. That one has a perfectly normal ARM64 kernel image, but diffoscope still shows a large diff when comparing two builds of the same boot.img.unpacked/kernel. Do I need to preprocess this kernel image somehow before comparing? Not sure if I need to strip signatures from the image or how to do this, by the way.

Aside from this, I've also used unpack_bootimg.py to unpack the boot.img. That one has a perfectly normal ARM64 kernel image, but diffoscope still shows a large diff when comparing two builds of the same boot.img.unpacked/kernel. Do I need to preprocess this kernel image somehow before comparing? Not sure if I need to strip signatures from the image or how to do this, by the way.

jack: when I hit a weird filetype, especially when it's likely others have it it, searching its filename in github code search helps... when you know how to use it, which is non-obvious: use a regex to search

• https://github.com/search?q=%2Fpvmfw.img%2F&type=code

In reply to @samueldr:matrix.org

jack: when I hit a weird filetype, especially when it's likely others have it it, searching its filename in github code search helps... when you know how to use it, which is non-obvious: use a regex to search

• https://github.com/search?q=%2Fpvmfw.img%2F&type=code

In reply to @jack:unredacted.org

Aside from this, I've also used unpack_bootimg.py to unpack the boot.img. That one has a perfectly normal ARM64 kernel image, but diffoscope still shows a large diff when comparing two builds of the same boot.img.unpacked/kernel. Do I need to preprocess this kernel image somehow before comparing? Not sure if I need to strip signatures from the image or how to do this, by the way.

In reply to @jack:unredacted.org
Any idea on this one?

In reply to @jack:unredacted.org

Aside from this, I've also used unpack_bootimg.py to unpack the boot.img. That one has a perfectly normal ARM64 kernel image, but diffoscope still shows a large diff when comparing two builds of the same boot.img.unpacked/kernel. Do I need to preprocess this kernel image somehow before comparing? Not sure if I need to strip signatures from the image or how to do this, by the way.

In reply to @jack:unredacted.org

Aside from this, I've also used unpack_bootimg.pyto unpack the boot.img. That one has a perfectly normal ARM64 kernel image, but diffoscope still shows a large diff when comparing two builds of the same boot.img.unpacked/kernel. Do I need to preprocess this kernel image somehow before comparing? Not sure if I need to strip signatures from the image or how to do this, by the way.

• https://source.android.com/docs/core/virtualization/architecture#firmware

The pVM firmware (pvmfw) is the first code executed by a pVM, similar to the boot ROM of a physical device.

Yes, maybe unpack_bootimg.py isn't prepared to handle it, so it just considers whatever is in the supposed kernel position on the file.