Currently, rcx is read as the fourth parameter of syscall on x86_64. But x86_64 Linux System Call convention uses r10 actually. This commit adds the wrapper for users who want to access to syscall params to analyze the user space. Changelog: ---------- v1 -> v2: - Rebase to current bpf-next https://lore.kernel.org/bpf/20211222213924.1869758-1-andrii@xxxxxxxxxx/ v2 -> v3: - Modify the definition of SYSCALL macros for only targeted archs. - Define __BPF_TARGET_MISSING variants for completeness. - Remove CORE variants. These macros will not be used. - Add a selftest. Signed-off-by: Kenta Tada <Kenta.Tada@xxxxxxxx> --- tools/lib/bpf/bpf_tracing.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h index 90f56b0f585f..d209e75dbdbd 100644 --- a/tools/lib/bpf/bpf_tracing.h +++ b/tools/lib/bpf/bpf_tracing.h @@ -70,6 +70,7 @@ #define __PT_PARM2_REG si #define __PT_PARM3_REG dx #define __PT_PARM4_REG cx +#define __PT_PARM4_REG_SYSCALL r10 /* syscall uses r10 */ #define __PT_PARM5_REG r8 #define __PT_RET_REG sp #define __PT_FP_REG bp @@ -99,6 +100,7 @@ #define __PT_PARM2_REG rsi #define __PT_PARM3_REG rdx #define __PT_PARM4_REG rcx +#define __PT_PARM4_REG_SYSCALL r10 /* syscall uses r10 */ #define __PT_PARM5_REG r8 #define __PT_RET_REG rsp #define __PT_FP_REG rbp @@ -263,6 +265,16 @@ struct pt_regs; #endif +#define PT_REGS_PARM1_SYSCALL(x) PT_REGS_PARM1(x) +#define PT_REGS_PARM2_SYSCALL(x) PT_REGS_PARM2(x) +#define PT_REGS_PARM3_SYSCALL(x) PT_REGS_PARM3(x) +#ifdef __PT_PARM4_REG_SYSCALL +#define PT_REGS_PARM4_SYSCALL(x) (__PT_REGS_CAST(x)->__PT_PARM4_REG_SYSCALL) +#else /* __PT_PARM4_REG_SYSCALL */ +#define PT_REGS_PARM4_SYSCALL(x) PT_REGS_PARM4(x) +#endif +#define PT_REGS_PARM5_SYSCALL(x) PT_REGS_PARM5(x) + #else /* defined(bpf_target_defined) */ #define PT_REGS_PARM1(x) ({ _Pragma(__BPF_TARGET_MISSING); 0l; }) @@ -290,6 +302,12 @@ struct pt_regs; #define BPF_KPROBE_READ_RET_IP(ip, ctx) ({ _Pragma(__BPF_TARGET_MISSING); 0l; }) #define BPF_KRETPROBE_READ_RET_IP(ip, ctx) ({ _Pragma(__BPF_TARGET_MISSING); 0l; }) +#define PT_REGS_PARM1_SYSCALL(x) ({ _Pragma(__BPF_TARGET_MISSING); 0l; }) +#define PT_REGS_PARM2_SYSCALL(x) ({ _Pragma(__BPF_TARGET_MISSING); 0l; }) +#define PT_REGS_PARM3_SYSCALL(x) ({ _Pragma(__BPF_TARGET_MISSING); 0l; }) +#define PT_REGS_PARM4_SYSCALL(x) ({ _Pragma(__BPF_TARGET_MISSING); 0l; }) +#define PT_REGS_PARM5_SYSCALL(x) ({ _Pragma(__BPF_TARGET_MISSING); 0l; }) + #endif /* defined(bpf_target_defined) */ #ifndef ___bpf_concat -- 2.32.0
