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I've CC'd the linux-debuggers mailing list here, which I believe would be its inaugural post! I think anybody interested in debugging kernel core dumps could use any answers you have. First, regarding naming. I guess I always assumed that "diskdump" referred to some older utility which performed the same function that makedumpfile now is commonly used for. Is that the case? Do you know the origin of the diskdump format? Do you know where to find the code for this older diskdump tool, if it existed? Second, I have some confusion regarding headers. I've seen headers for files with the content "DISKDUMP" and "KDUMP " -- and according to src/kdumpfile/diskdump.c, you have too. diskdump_probe() shows that you check for these two headers and set a different description depending on which is seen. Do you know why or where these two headers are set, and which one is chose in which situation? Third, sometimes I see an additional header with signature "makedumpfile", and a few 64-bit integer fields, and then the KDUMP/DISKDUMP header occurs at offset 4096/0x1000. I wonder if you're familiar with that header, why or why not it occurs? Finally, and this one is a long shot, do you know any good central document describing the diskdump / kdump format? From everything I can tell, it seems very much like a "living standard", one which lives in code more than documentation. But I would be glad to be wrong here, if there's a document which describes the format then I'd love to read it, and if not, maybe I could be part of creating it to help everyone out. Thanks, Stephen