microblaze: Fix sys_clone syscall

sys_clone syscall ignored args which this patch mapped to args
which are passing from glibc.

Here is the origin problem description.

"I ran the static libgcc tests (very few of them are there, they are
mostly dynamically linked) and some of  them fail with an assertion in
fork() system call (tid != pid), I looked at the microblaze/entry.S
file and it looks suspicious (ignores arguments 3-5)"

Arg mapping should be:
glibc ARCH_FORK(...) -> do_fork(...)
r5 -> r5   (clone_flags)
r6  -> r6 (stack_start, use parent->stack if NULL)
pt_regs -> r7 (pt_regs)
r7 -> r8 (stack_size)
r8 -> r9 (parent_tidptr)
r9 -> r10 (child_tidptr)

Signed-off-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>

diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
index c0ede25..077377a 100644 (file)
--- a/arch/microblaze/kernel/entry.S
+++ b/arch/microblaze/kernel/entry.S
@@ -476,13 +476,13 @@ C_ENTRY(sys_vfork):
 
 C_ENTRY(sys_clone):
        bnei    r6, 1f;                 /* See if child SP arg (arg 1) is 0. */
-       lwi     r6, r1, PTO+PT_R1;      /* If so, use paret's stack ptr */
-1:     la      r7, r1, PTO;                    /* Arg 2: parent context */
-       add     r8, r0, r0;                     /* Arg 3: (unused) */
-       add     r9, r0, r0;                     /* Arg 4: (unused) */
-       add     r10, r0, r0;                    /* Arg 5: (unused) */
-       brid    do_fork         /* Do real work (tail-call) */
-       nop;
+       lwi     r6, r1, PTO + PT_R1;    /* If so, use paret's stack ptr */
+1:     add     r10, r0, r9;            /* Arg 6: (child_tidptr) */
+       add     r9, r0, r8;             /* Arg 5: (parent_tidptr) */
+       add     r8, r0, r7;             /* Arg 4: (stack_size) */
+       la      r7, r1, PTO;            /* Arg 3: pt_regs  */
+       brid    do_fork                 /* Do real work (tail-call) */
+       nop
 
 C_ENTRY(sys_execve):
        la      r8, r1, PTO;            /* add user context as 4th arg */