selftests/bpf: ignore call depth accounting for retbleed in verifier tests

When running the selftests on a retbleed-affected platform (eg:
Skylake), with call depth accounting enabled
(CONFIG_CALL_DEPTH_TRACKING=y) _and_ with retbleed=stuff, some verifier
selftests fail to validate the jited instructions. For example:

  MATCHED    SUBSTR: '	endbr64'
  MATCHED    SUBSTR: '	nopl	(%rax,%rax)'
  MATCHED    SUBSTR: '	xorq	%rax, %rax'
  MATCHED    SUBSTR: '	pushq	%rbp'
  MATCHED    SUBSTR: '	movq	%rsp, %rbp'
  MATCHED    SUBSTR: '	endbr64'
  MATCHED    SUBSTR: '	cmpq	$0x21, %rax'
  MATCHED    SUBSTR: '	ja	L0'
  MATCHED    SUBSTR: '	pushq	%rax'
  MATCHED    SUBSTR: '	movq	%rsp, %rax'
  MATCHED    SUBSTR: '	jmp	L1'
  MATCHED    SUBSTR: 'L0:	pushq	%rax'
  MATCHED    SUBSTR: 'L1:	pushq	%rax'
  MATCHED    SUBSTR: '	movq	-0x10(%rbp), %rax'
  WRONG LINE  REGEX: '	callq	0x{{.*}}'

Those affected selftests allways fail on some call instruction: this
failure is due to the JIT compiler emitting call depth accounting for
retbleed mitigation (see x86_call_depth_emit_accounting calls in
bpf_jit_comp.c), resulting in an additional instruction being inserted
in front of every call instruction, similar to this one:

  sarq    $0x5, %gs:-0x39882741(%rip)

Fix those selftests by allowing them to ignore this possibly present
call depth accounting instruction.

Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260528-fix_tests_for_retbleed_stuff-v1-1-c2022a1f3bee@bootlin.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

0 files changed, 0 insertions, 0 deletions