On arm64, the first syscall argument should be accessed via orig_x0 (see arch/arm64/include/asm/syscall.h). Currently regs[0] is used instead, leading to bpf_syscall_macro test failure. Note that this is unfixable for CO-RE when vmlinux.h is not included. Simply fail the build in this case. Reported-by: Heiko Carstens <hca@xxxxxxxxxxxxx> Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> --- tools/lib/bpf/bpf_tracing.h | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h index 5911b177728f..f5541add5880 100644 --- a/tools/lib/bpf/bpf_tracing.h +++ b/tools/lib/bpf/bpf_tracing.h @@ -164,9 +164,21 @@ #define __BPF_ARCH_HAS_SYSCALL_WRAPPER -#if !defined(__KERNEL__) && !defined(__VMLINUX_H__) +#if defined(__KERNEL__) || defined(__VMLINUX_H__) +#define __PT_PARM1_REG_SYSCALL orig_x0 +#else /* arm64 provides struct user_pt_regs instead of struct pt_regs to userspace */ #define __PT_REGS_CAST(x) ((const struct user_pt_regs *)(x)) +/* + * struct pt_regs.orig_x0 is not exposed through struct user_pt_regs, and the + * ABI prohibits extending struct user_pt_regs. In non-CO-RE case, make use of + * the fact that orig_x0 comes right after pstate in struct pt_regs. CO-RE does + * not allow such hacks, so there is no way to access orig_x0. + */ +#define PT_REGS_PARM1_SYSCALL(x) \ + (*(unsigned long *)(((char *)(x) + \ + offsetofend(struct user_pt_regs, pstate)))) +#define __PT_PARM1_REG_SYSCALL __unsupported__ #endif #define __PT_PARM1_REG regs[0] -- 2.34.1
