3 Commits

Author	SHA1	Message	Date
Andrii Nakryiko	ff943683f8	selftests/bpf: fix uprobe offset calculation in selftests ... Fix how selftests determine relative offset of a function that is uprobed. Previously, there was an assumption that uprobed function is always in the first executable region, which is not always the case (libbpf CI hits this case now). So get_base_addr() approach in isolation doesn't work anymore. So teach get_uprobe_offset() to determine correct memory mapping and calculate uprobe offset correctly. While at it, I merged together two implementations of get_uprobe_offset() helper, moving powerpc64-specific logic inside (had to add extra {} block to avoid unused variable error for insn). Also ensured that uprobed functions are never inlined, but are still static (and thus local to each selftest), by using a no-op asm volatile block internally. I didn't want to keep them global __weak, because some tests use uprobe's ref counter offset (to test USDT-like logic) which is not compatible with non-refcounted uprobe. So it's nicer to have each test uprobe target local to the file and guaranteed to not be inlined or skipped by the compiler (which can happen with static functions, especially if compiling selftests with -O2). Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20220126193058.3390292-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>	2022-01-26 20:04:01 -08:00
Jean-Philippe Brucker	3a029e1f3d	selftests/bpf: Fix build of task_pt_regs test for arm64 ... struct pt_regs is not exported to userspace on all archs. arm64 and s390 export "user_pt_regs" instead, which causes build failure at the moment: progs/test_task_pt_regs.c:8:16: error: variable has incomplete type 'struct pt_regs' struct pt_regs current_regs = {}; Instead of using pt_regs from ptrace.h, use the larger kernel struct from vmlinux.h directly. Since the test runner task_pt_regs.c does not have access to the kernel struct definition, copy it into a char array. Fixes: 576d47bb1a92 ("bpf: selftests: Add bpf_task_pt_regs() selftest") Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Link: https://lore.kernel.org/bpf/20210906163635.302307-1-jean-philippe@linaro.org	2021-09-07 17:23:19 +02:00
Daniel Xu	576d47bb1a	bpf: selftests: Add bpf_task_pt_regs() selftest ... This test retrieves the uprobe's pt_regs in two different ways and compares the contents in an arch-agnostic way. Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/5581eb8800f6625ec8813fe21e9dce1fbdef4937.1629772842.git.dxu@dxuuu.xyz	2021-08-25 10:37:05 -07:00