From 994064c84e86c1be21365f2041ca5cb4bbd3e921 Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Tue, 26 Oct 2004 20:48:18 +0000 Subject: Atsushi Nemoto writes: >>>>> On Tue, 19 Oct 2004 13:28:34 -0600, Erik Andersen said: >> BTW, top of uClibc TODO list is "Fix syscall() on mips". What is a >> problem? andersen> It appears that uClibc's syscall() for mips works ok for andersen> syscalls with a few arguments. But as I recall, it does not andersen> work properly with _syscall5, _syscall6, _syscall7, etc. andersen> Perhaps there is some mistake in its assumptions about the andersen> mips/linux ABI regarding which syscall arguments are passed andersen> via register vs which syscall arguments are passed on the andersen> stack. Hmm... I found a old fix in uClibc ML archive. http://www.uclibc.org/lists/uclibc/2002-September/004459.html But it seems somewhat broken. How about this fix instead? I tested mmap with syscall() in mips. mips64 is not tested. --- libc/sysdeps/linux/mips/syscall.S | 40 ++++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 15 deletions(-) diff --git a/libc/sysdeps/linux/mips/syscall.S b/libc/sysdeps/linux/mips/syscall.S index b270e315b..ce2f1292f 100644 --- a/libc/sysdeps/linux/mips/syscall.S +++ b/libc/sysdeps/linux/mips/syscall.S @@ -33,23 +33,33 @@ syscall: move a0, a1 /* Move the next three args up a register. */ move a1, a2 move a2, a3 - /* Load the remaining possible args (up to 11) from the stack. */ + /* Load the remaining possible args (up to 7) from the stack. */ #ifdef __mips64 - ld t0,4*8(sp) - ld t1,5*8(sp) - ld t2,6*8(sp) - ld t3,7*8(sp) - ld t4,8*8(sp) - ld t5,9*8(sp) - ld t6,10*8(sp) + move a3, a4 + move a4, a5 + move a5, a6 + move a6, a7 + daddiu sp,sp,-16 + sd v0,0*8(sp) + ld v0,0*8(sp) /* for system call restarts */ #else - lw t0,4*4(sp) - lw t1,5*4(sp) - lw t2,6*4(sp) - lw t3,7*4(sp) - lw t4,8*4(sp) - lw t5,9*4(sp) - lw t6,10*4(sp) + lw a3,4*4(sp) + lw t0,5*4(sp) + lw t1,6*4(sp) + lw t2,7*4(sp) + addiu sp,sp,-32 + sw t0,4*4(sp) + sw t1,5*4(sp) + sw t2,6*4(sp) + sw v0,7*4(sp) + lw v0,7*4(sp) /* for system call restarts */ #endif syscall /* Do the system call. */ +#ifdef __mips64 + daddiu sp,sp,16 +#else + addiu sp,sp,32 +#endif j ra /* Return to caller. */ +.end syscall +.size syscall,.-syscall -- cgit v1.2.3