Unable to analyze xen guest coredump

[letsjmp]

I start the domU with linux 4.12.13(bzImage) and xen 4.9.0, and I manually dump the guest memory with sudo xl dump-core myvm dump-res.

Then I try to analyze it in crash using sudo crash bzImage dump-res, but it tells me that

crash: bzImage: not a supported file format I have tried to add -f option using sudo crash bzImage dump-res, but got the same error.

I then replace the bzImage with corresponding vmlinux, this time it gives me the following message

WARNING: cannot read linux_banner string crash: src/linux-4.12.13/vmlinux and dump-res do not match!

How can I make them match? Xen does not support directly boot a uncompressed vmlinux file(in HVM mode) so I have keep using bzImage.

Thanks

[crash-utility]

----- Original Message -----

I start the domU with linux 4.12.13(bzImage) and xen 4.9.0, and I manually dump the guest memory with sudo xl dump-core myvm dump-res.

Then I try to analyze it in crash using sudo crash bzImage dump-res, but it tells me that

crash: bzImage: not a supported file format I have tried to add -f option using sudo crash bzImage dump-res, but got the same error.

I then replace the bzImage with corresponding vmlinux, this time it gives me the following message

WARNING: cannot read linux_banner string crash: src/linux-4.12.13/vmlinux and dump-res do not match!

How can I make them match? Xen does not support directly boot a uncompressed vmlinux file(in HVM mode) so I have keep using bzImage.

Thanks

I cannot help you with Xen-related issues because Red Hat stopped releasing Xen kernels several years ago (RHEL5 was the last Red Hat kernel that contained a Xen kernel). Since then, ongoing Xen kernel support in the crash utility has been maintained by engineers who work for other distributions that still offer Xen kernels.

What I can tell you is that you have no choice but to use the vmlinux file, which contains all of the symbol and debuginfo data that crash relies upon. So that is not a problem, as x86 kernels have always booted bzImage files. I do not know why the reading of the dump-res file is failing. It is possible that something has changed with xen 4.9.0.

Please post your query on the [email protected] mailing list:

https://www.redhat.com/mailman/listinfo/crash-utility

There are several Xen maintainers on the mailing list who may be able to help you.

Dave

[letsjmp]

Thanks Dave, I'll post it in the mailing list.