Hi,
just want to let you know that I did a git bisect with Linux v5.3-rc2
(where the problem also exists) and the result (details see [1]):
e55a73251da335873a6e87d68fb17e5aabb8978e is the first bad commit
commit e55a73251da335873a6e87d68fb17e5aabb8978e
Author: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Date: Thu Jun 27 20:50:47 2019 -0500
bpf: Fix ORC unwinding in non-JIT BPF code
Objtool previously ignored ___bpf_prog_run() because it didn't understand
the jump table. This resulted in the ORC unwinder not being able to unwind
through non-JIT BPF code.
Now that objtool knows how to read jump tables, remove the whitelist and
annotate the jump table so objtool can recognize it.
Also add an additional "const" to the jump table definition to clarify that
the text pointers are constant. Otherwise GCC sets the section writable
flag and the assembler spits out warnings.
Fixes: d15d356887e7 ("perf/x86: Make perf callchains work without
CONFIG_FRAME_POINTER")
Reported-by: Song Liu <songliubraving@xxxxxx>
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Kairui Song <kasong@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/881939122b88f32be4c374d248c09d7527a87e35.1561685471.git.jpoimboe@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
:040000 040000 4735e9d14fa416c1c361ec3923440a3d586a627d
31de80b85c7b0292e47a719ecb6b1a451de2f8ef M kernel
Maybe you want to look at this, too.
The object files are attached in [2].
Thanks,
- Sedat -
[0] https://github.com/ClangBuiltLinux/linux/issues/619
[1] https://github.com/ClangBuiltLinux/linux/issues/619#issuecomment-517152467
[2] https://github.com/ClangBuiltLinux/linux/issues/619#issuecomment-517159635
