From 060581c158a66fcc68f8877ccd0d60fd9aeca65e Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 11 Aug 2018 01:04:55 +0100 Subject: alpha: use alpha_ni_syscall only for syscall zero Once upon a time it used to have a C part that printed a warning about unimplemented OSF syscalls. That's what it's been doing all over the OSF syscall range, while the native Linux syscall range uses sys_ni_syscall(). With those warnings about unimplemented OSF syscalls gone (circa 2.4), alpha_ni_syscall() has shrunk to that little bit of asm and the only reason it hasn't been replaced with sys_ni_syscall() everywhere is that extra twist needed in case of syscall #0. Let's keep it only for syscall #0 and replace the rest with sys_ni_syscall. And use sys_ni_syscall for "number out range" in ptraced-call case, as we'd been doing for normal codepath since 2.1.86... Acked-by: Richard Henderson Signed-off-by: Al Viro --- arch/alpha/kernel/entry.S | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) (limited to 'arch/alpha/kernel/entry.S') diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S index c64806a2daf5..21840e7042f3 100644 --- a/arch/alpha/kernel/entry.S +++ b/arch/alpha/kernel/entry.S @@ -473,7 +473,7 @@ entSys: bne $3, strace beq $4, 1f ldq $27, 0($5) -1: jsr $26, ($27), alpha_ni_syscall +1: jsr $26, ($27), sys_ni_syscall ldgp $gp, 0($26) blt $0, $syscall_error /* the call failed */ stq $0, 0($sp) @@ -587,7 +587,7 @@ strace: /* get the system call pointer.. */ lda $1, NR_SYSCALLS($31) lda $2, sys_call_table - lda $27, alpha_ni_syscall + lda $27, sys_ni_syscall cmpult $0, $1, $1 s8addq $0, $2, $2 beq $1, 1f @@ -843,15 +843,20 @@ sys_rt_sigreturn: .end sys_rt_sigreturn .align 4 - .globl alpha_ni_syscall - .ent alpha_ni_syscall -alpha_ni_syscall: + .globl alpha_syscall_zero + .ent alpha_syscall_zero +alpha_syscall_zero: .prologue 0 - /* Special because it also implements overflow handling via - syscall number 0. And if you recall, zero is a special - trigger for "not an error". Store large non-zero there. */ + /* Special because it needs to do something opposite to + force_successful_syscall_return(). We use the saved + syscall number for that, zero meaning "not an error". + That works nicely, but for real syscall 0 we need to + make sure that this logics doesn't get confused. + Store a non-zero there - -ENOSYS we need in register + for our return value will do just fine. + */ lda $0, -ENOSYS unop stq $0, 0($sp) ret -.end alpha_ni_syscall +.end alpha_syscall_zero -- cgit v1.2.3