Re: [PATCH -tip perf/probes 00/10] x86 insn decoder bugfixes

From: Roland McGrath
Date: Thu Oct 29 2009 - 15:19:17 EST


> Thirdly, i think we should expose the build-id of the kernel and the
> path to the vmlinux (and modules) via /proc/build-id or so. That way
> tooling can find the vmlinux file and can validate that it matches the
> kernel's signature. (maybe include a file date as well - that's a faster
> check than a full build-id checksum, especially for large kernels)

You seem to be confused about what build IDs are. There is no "checksum
validation". Once the bits are stored there is no calculation ever done
again, only exact comparison with an expected build ID bitstring. The size
of an object file is immaterial.

As Frank mentioned, the kernel's and modules' allocated ELF notes (and thus
build IDs) are already exposed in /sys. Tools like "eu-unstrip -nk" use
this information today.


Thanks,
Roland
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/