[patch 10/18] entry: Use syscall number instead of rereading it

[Jinjie Ruan]

On 7/8/2026 3:06 AM, Thomas Gleixner wrote:
> rseq_syscall_enter_work() is invoked before the syscall number can be
> modified. So there is no point in rereading it from pt_regs.
> 
> Signed-off-by: Thomas Gleixner <tglx at kernel.org>
> ---
>  include/linux/entry-common.h |    9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> --- a/include/linux/entry-common.h
> +++ b/include/linux/entry-common.h
> @@ -70,9 +70,10 @@ static inline void syscall_enter_audit(s
>  	}
>  }
>  
> -static __always_inline long syscall_trace_enter(struct pt_regs *regs, unsigned long work)
> +static __always_inline long syscall_trace_enter(struct pt_regs *regs, unsigned long work,
> +						long syscall)
>  {
> -	long syscall, ret = 0;
> +	long ret = 0;
>  
>  	/*
>  	 * Handle Syscall User Dispatch.  This must comes first, since
> @@ -90,7 +91,7 @@ static __always_inline long syscall_trac
>  	 * through hrtimer_interrupt().
>  	 */
>  	if (work & SYSCALL_WORK_SYSCALL_RSEQ_SLICE)
> -		rseq_syscall_enter_work(syscall_get_nr(current, regs));
> +		rseq_syscall_enter_work(syscall);
>  
>  	/* Handle ptrace */
>  	if (work & (SYSCALL_WORK_SYSCALL_TRACE | SYSCALL_WORK_SYSCALL_EMU)) {
> @@ -145,7 +146,7 @@ static __always_inline long syscall_ente
>  	unsigned long work = READ_ONCE(current_thread_info()->syscall_work);
>  
>  	if (work & SYSCALL_WORK_ENTER)
> -		syscall = syscall_trace_enter(regs, work);
> +		syscall = syscall_trace_enter(regs, work, syscall);

Reviewed-by: Jinjie Ruan <ruanjinjie at huawei.com>

>  
>  	return syscall;
>  }
>