Re: FAILED unresolved symbol vfs_truncate on arm64 with LLVM

On Thu, Feb 11, 2021 at 04:43:48PM +0100, Sedat Dilek wrote:

SNIP

quoted

quoted

filled with elf functions start/end values, right?

quoted

                        /*
                         * We iterate over sorted array, so we can easily skip
                         * not valid item and move following valid field into


So the idea is to use address segments and check whether there is a
segment that overlaps with a given address by first binary searching
for a segment with the largest starting address that is <= addr. And
then just confirming that segment does overlap with the requested
address.

WDYT?

heya,
with your approach I ended up with change below, it gives me same
results as with the previous change

I think I'll separate the kmod bool address computation later on,
but I did not want to confuse this change for now

I have applied your diff on top of pahole-v1.20 with Yonghong Son's
"btf_encoder: sanitize non-regular int base type" applied.
This is on x86-64 with LLVM-12, so I am not directly affected.
If it is out of interest I can offer vmlinux (or .*btf* files) w/ and
w/o your diff.

if you could run your tests/workloads and check the new change does not
break your stuff, that'd be great

we need soem testsuite ;-) I have some stupid test script which runs over
few vmlinux binaries and check the diff in BTF data.. problem is that these
vmlinux binaries are ~300M each, so it's not great for sharing

also I was checking if we could use BPF_BTF_LOAD syscall and load BTF in
kernel and back at the end of pahole processing to check it's valid ;-)

thanks,
jirka