libbpf now has macros to access syscall arguments in an architecture-agnostic manner, but unfortunately they have a number of issues on non-Intel arches, that this series aims to fix. v1: https://lore.kernel.org/bpf/20220201234200.1836443-1-iii@xxxxxxxxxxxxx/ v1 -> v2: * Put orig_gpr2 in place of args[1] on s390 (Vasily). * Fix arm64, powerpc and riscv (Heiko). The arm64 fix is similar to the s390 one. powerpc and riscv are different in that they unpack arguments to registers before invoking syscall handlers - libbpf needs to know about this difference, so I've decided to introduce PT_REGS_SYSCALL macro for this (see bpf_syscall_macro test for usage example). Tested in QEMU. @Catalin, @Michael, @Paul: could you please review the arm64, powerpc and riscv parts? Ilya Leoshkevich (10): arm64/bpf: Add orig_x0 to user_pt_regs s390/bpf: Add orig_gpr2 to user_pt_regs selftests/bpf: Fix an endianness issue in bpf_syscall_macro test libbpf: Add __PT_PARM1_REG_SYSCALL macro libbpf: Add PT_REGS_SYSCALL macro selftests/bpf: Use PT_REGS_SYSCALL in bpf_syscall_macro libbpf: Fix accessing the first syscall argument on arm64 libbpf: Fix accessing syscall arguments on powerpc libbpf: Fix accessing syscall arguments on riscv libbpf: Fix accessing the first syscall argument on s390 arch/arm64/include/asm/ptrace.h | 2 +- arch/arm64/include/uapi/asm/ptrace.h | 1 + arch/s390/include/asm/ptrace.h | 3 +-- arch/s390/include/uapi/asm/ptrace.h | 2 +- tools/lib/bpf/bpf_tracing.h | 23 ++++++++++++++++++- .../selftests/bpf/progs/bpf_syscall_macro.c | 7 ++++-- 6 files changed, 31 insertions(+), 7 deletions(-) -- 2.34.1
