Ftrace, KASLR and gdb

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Ftrace is a jewel to dig into the kernel, be it for troubleshooting, perf tuning or just understanding. But when one needs to disassemble the running kernel (eg to move kprobes around in a function, in order to understand a given code path), KASLR makes it impossible for gdb to get useful symbol addresses, even with a debug image. That said, /proc/kallsyms always gives the accurate, present symbol addresses. But, to my knowledge, gdb isn't able to import /proc/kallsyms as a symbol table. To circumvent this, I've written a small userland tool, usling libbfd, that creates an ELF file out of /proc/kallsyms. Passing this ELF file to gdb instead of "vmlinux", and /proc/kcore as core, then allows for a perfect gdb session on the running kernel. Of course this ELF file is only valid until the next reboot, but that's okay as its creation is fast.

Now, my question: did I miss an alternative ?

In other words, is there some kind of "kallsyms plug-in" for gdb somewhere ?
Or, taking the problem from the other side, some kernel module exposing a "/proc/kallsyms.elf" or similar, for direct consumption by gdb ?
Or another method, that people routinely use for the same purpose ?

Thanks in advance,


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