On Mon, Feb 7, 2022 at 9:16 PM Ilya Leoshkevich <iii@xxxxxxxxxxxxx> wrote: > > Depending on whether or not an arch has ARCH_HAS_SYSCALL_WRAPPER, > syscall arguments must be accessed through a different set of > registers. Provide PT_REGS_SYSCALL_REGS macro to abstract away > that difference. > > Reported-by: Heiko Carstens <hca@xxxxxxxxxxxxx> > Co-developed-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> > --- Again, there was nothing wrong with the way you did it in v3, please revert to that one. > tools/lib/bpf/bpf_tracing.h | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h > index 82f1e935d549..7a015ee8fb11 100644 > --- a/tools/lib/bpf/bpf_tracing.h > +++ b/tools/lib/bpf/bpf_tracing.h > @@ -64,6 +64,8 @@ > > #if defined(bpf_target_x86) > > +#define __BPF_ARCH_HAS_SYSCALL_WRAPPER > + > #if defined(__KERNEL__) || defined(__VMLINUX_H__) > > #define __PT_PARM1_REG di > @@ -114,6 +116,8 @@ > > #elif defined(bpf_target_s390) > > +#define __BPF_ARCH_HAS_SYSCALL_WRAPPER > + > /* 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] > @@ -142,6 +146,8 @@ > > #elif defined(bpf_target_arm64) > > +#define __BPF_ARCH_HAS_SYSCALL_WRAPPER > + > /* arm64 provides struct user_pt_regs instead of struct pt_regs to userspace */ > #define __PT_REGS_CAST(x) ((const struct user_pt_regs *)(x)) > #define __PT_PARM1_REG regs[0] > @@ -344,6 +350,17 @@ struct pt_regs; > > #endif /* defined(bpf_target_defined) */ > > +/* > + * When invoked from a syscall handler BPF_KPROBE, returns a pointer to a > + * struct pt_regs containing syscall arguments, that is suitable for passing to > + * PT_REGS_PARMn_SYSCALL() and PT_REGS_PARMn_CORE_SYSCALL(). > + */ > +#ifdef __BPF_ARCH_HAS_SYSCALL_WRAPPER > +#define PT_REGS_SYSCALL_REGS(ctx) ((struct pt_regs *)PT_REGS_PARM1(ctx)) > +#else > +#define PT_REGS_SYSCALL_REGS(ctx) ctx > +#endif > + > #ifndef ___bpf_concat > #define ___bpf_concat(a, b) a ## b > #endif > -- > 2.34.1 >
