On s390, the first syscall argument should be accessed via orig_gpr2
(see arch/s390/include/asm/syscall.h). Currently gpr[2] is used
instead, leading to bpf_syscall_macro test failure.
Fixes: d084df3b7a4c ("libbpf: Fix the incorrect register read for syscalls on x86_64")
Reported-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
---
tools/lib/bpf/bpf_tracing.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h
index 2b707aff0763..cca62633f32c 100644
--- a/tools/lib/bpf/bpf_tracing.h
+++ b/tools/lib/bpf/bpf_tracing.h
@@ -117,6 +117,7 @@
/* s390 provides user_pt_regs instead of struct pt_regs to userspace */
#define __PT_REGS_CAST(x) ((const user_pt_regs *)(x))
#define __PT_PARM1_REG gprs[2]
+#define __PT_PARM1_REG_SYSCALL orig_gpr2
#define __PT_PARM2_REG gprs[3]
#define __PT_PARM3_REG gprs[4]
#define __PT_PARM4_REG gprs[5]
--
2.34.1
