On Fri, Jan 29, 2021 at 2:15 PM Paul Moore <paul@xxxxxxxxxxxxxx> wrote: > > On Mon, Jan 25, 2021 at 5:42 PM Alexei Starovoitov > <alexei.starovoitov@xxxxxxxxx> wrote: > > On Mon, Jan 25, 2021 at 12:54 PM Paul Moore <paul@xxxxxxxxxxxxxx> wrote: > > > > > > Hello all, > > > > > > My apologies if this has already been reported, but I didn't see > > > anything obvious with a quick search through the archives. I have a > > > test program that behaves very similar to the existing > > > selftest/bpf/test_verifier_log test that has started failing this week > > > with v5.11-rc5; it ran without problem last week on v5.11-rc4. Is > > > this a known problem with a fix already, or is this something new? > > > > > > % uname -r > > > 5.11.0-0.rc5.134.fc34.x86_64 > > > % pwd > > > /.../linux/tools/testing/selftests/bpf > > > % git log --oneline | head -n 1 > > > 6ee1d745b7c9 Linux 5.11-rc5 > > > % make test_verifier_log > > > ... > > > BINARY test_verifier_log > > > % ./test_verifier_log > > > Test log_level 0... > > > Test log_size < 128... > > > Test log_buff = NULL... > > > Test oversized buffer... > > > ERROR: Program load returned: ret:-1/errno:22, expected ret:-1/errno:13 > > > > Thanks for reporting. > > bpf and bpf-next don't have this issue. Not sure what changed. > > I haven't had a chance to look into this any further, but Ondrej > Mosnacek (CC'd) found the following today: > > "So I was trying to debug this further and I think I've identified what > triggers the problem. It seems that the BTF debuginfo generation > became broken with CONFIG_DEBUG_INFO_DWARF4=n somewhere between -rc4 > and -rc5. It also seems to depend on a recent (Fedora Rawhide) version > of some component of the build system (GCC, probably), because the > problem disappeared when I tried to build the "bad" kernel in F33 > buildroot instead of Rawhide." I see. There were fixes for dwarf and btf, but I lost the track. I believe it was a combination of gcc bug that was worked around in pahole. Arnaldo, Jiri, Andrii, what is the status? Did all fixes land in pahole?
