Re: [PATCH 12/13] riscv: define syscall_get_arch()

On Thu, 08 Nov 2018 19:17:13 PST (-0800), ldv(a)altlinux.org wrote: > syscall_get_arch() is required to be implemented on all architectures > that use tracehook_report_syscall_entry() in order to extend > the generic ptrace API with PTRACE_GET_SYSCALL_INFO request. > > Signed-off-by: Dmitry V. Levin <ldv(a)altlinux.org&gt; > --- > arch/riscv/include/asm/syscall.h | 6 ++++++ > include/uapi/linux/audit.h | 1 + > 2 files changed, 7 insertions(+) > > diff --git a/arch/riscv/include/asm/syscall.h b/arch/riscv/include/asm/syscall.h > index 8d25f8904c00..7e1e26ca7317 100644 > --- a/arch/riscv/include/asm/syscall.h > +++ b/arch/riscv/include/asm/syscall.h > @@ -18,6 +18,7 @@ > #ifndef _ASM_RISCV_SYSCALL_H > #define _ASM_RISCV_SYSCALL_H > > +#include <uapi/linux/audit.h> > #include <linux/sched.h> > #include <linux/err.h> > > @@ -99,4 +100,9 @@ static inline void syscall_set_arguments(struct task_struct *task, > memcpy(&regs->a1 + i * sizeof(regs->a1), args, n * sizeof(regs->a0)); > } > > +static inline int syscall_get_arch(void) > +{ > + return AUDIT_ARCH_RISCV; > +} > + > #endif /* _ASM_RISCV_SYSCALL_H */ > diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h > index c4c8b131af48..ad4105c602a1 100644 > --- a/include/uapi/linux/audit.h > +++ b/include/uapi/linux/audit.h > @@ -405,6 +405,7 @@ enum { > /* do not define AUDIT_ARCH_PPCLE since it is not supported by audit */ > #define AUDIT_ARCH_PPC64 (EM_PPC64|__AUDIT_ARCH_64BIT) > #define AUDIT_ARCH_PPC64LE (EM_PPC64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE) > +#define AUDIT_ARCH_RISCV (EM_RISCV|__AUDIT_ARCH_64BIT) > #define AUDIT_ARCH_S390 (EM_S390) > #define AUDIT_ARCH_S390X (EM_S390|__AUDIT_ARCH_64BIT) > #define AUDIT_ARCH_SH (EM_SH) I think this is incorrect: EM_RISCV has 32-bit and 64-bit variants, and if I understand what's going on here this is marking all RISC-V targets as 64-bit. Since this is a userspace header, I think the right thing to switch on is __riscv_xlen, which will be defined to either 32 or 64 depending on the base ISA. We're also little endian.