[PATCH] uml: fork cleanup

Fix the do_fork calling convention: normal arch pass the regs and the new sp
value to do_fork instead of NULL.

Currently the arch-independent code ignores these values, while the UML code
(actually it's copy_thread) gets the right values by itself.

With this patch, things are fixed up.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

6 files changed, 19 insertions, 81 deletions

diff --git a/arch/um/kernel/process_kern.c b/arch/um/kernel/process_kern.c
index 157584ae4792..0c57bc6e3747 100644
--- a/arch/um/kernel/process_kern.c
+++ b/arch/um/kernel/process_kern.c
@@ -96,8 +96,8 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 
         current->thread.request.u.thread.proc = fn;
         current->thread.request.u.thread.arg = arg;
-        pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0, NULL, 0, NULL,
-                      NULL);
+        pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0,
+                      &current->thread.regs, 0, NULL, NULL);
         if(pid < 0)
                 panic("do_fork failed in kernel_thread, errno = %d", pid);
         return(pid);
diff --git a/arch/um/kernel/skas/process_kern.c b/arch/um/kernel/skas/process_kern.c
index fc71ef295782..8f0607f54b7a 100644
--- a/arch/um/kernel/skas/process_kern.c
+++ b/arch/um/kernel/skas/process_kern.c
@@ -111,8 +111,7 @@ int copy_thread_skas(int nr, unsigned long clone_flags, unsigned long sp,
         void (*handler)(int);
 
         if(current->thread.forking){
-                memcpy(&p->thread.regs.regs.skas, 
-                       &current->thread.regs.regs.skas, 
+                memcpy(&p->thread.regs.regs.skas, &regs->regs.skas,
                        sizeof(p->thread.regs.regs.skas));
                 REGS_SET_SYSCALL_RETURN(p->thread.regs.regs.skas.regs, 0);
                 if(sp != 0) REGS_SP(p->thread.regs.regs.skas.regs) = sp;
@@ -201,14 +200,3 @@ int thread_pid_skas(struct task_struct *task)
 #warning Need to look up userspace_pid by cpu
         return(userspace_pid[0]);
 }
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/kernel/syscall_kern.c b/arch/um/kernel/syscall_kern.c
index b7a55251e897..8e1a3501ff46 100644
--- a/arch/um/kernel/syscall_kern.c
+++ b/arch/um/kernel/syscall_kern.c
@@ -31,7 +31,8 @@ long sys_fork(void)
         long ret;
 
         current->thread.forking = 1;
-        ret = do_fork(SIGCHLD, 0, NULL, 0, NULL, NULL);
+        ret = do_fork(SIGCHLD, UPT_SP(&current->thread.regs.regs),
+                      &current->thread.regs, 0, NULL, NULL);
         current->thread.forking = 0;
         return(ret);
 }
@@ -41,8 +42,9 @@ long sys_vfork(void)
         long ret;
 
         current->thread.forking = 1;
-        ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, NULL, 0, NULL,
-                      NULL);
+        ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD,
+                      UPT_SP(&current->thread.regs.regs),
+                      &current->thread.regs, 0, NULL, NULL);
         current->thread.forking = 0;
         return(ret);
 }
@@ -162,14 +164,3 @@ int next_syscall_index(int limit)
         spin_unlock(&syscall_lock);
         return(ret);
 }
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/kernel/tt/process_kern.c b/arch/um/kernel/tt/process_kern.c
index 776310fd5b8b..a189a2b92935 100644
--- a/arch/um/kernel/tt/process_kern.c
+++ b/arch/um/kernel/tt/process_kern.c
@@ -266,10 +266,10 @@ int copy_thread_tt(int nr, unsigned long clone_flags, unsigned long sp,
         }
 
         if(current->thread.forking){
-                sc_to_sc(UPT_SC(&p->thread.regs.regs), 
-                         UPT_SC(&current->thread.regs.regs));
+                sc_to_sc(UPT_SC(&p->thread.regs.regs), UPT_SC(&regs->regs));
                 SC_SET_SYSCALL_RETURN(UPT_SC(&p->thread.regs.regs), 0);
-                if(sp != 0) SC_SP(UPT_SC(&p->thread.regs.regs)) = sp;
+                if(sp != 0)
+                        SC_SP(UPT_SC(&p->thread.regs.regs)) = sp;
         }
         p->thread.mode.tt.extern_pid = new_pid;
 
@@ -459,14 +459,3 @@ int is_valid_pid(int pid)
         read_unlock(&tasklist_lock);
         return(0);
 }
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/sys-i386/syscalls.c b/arch/um/sys-i386/syscalls.c
index 335e2d89504d..83e9be820a86 100644
--- a/arch/um/sys-i386/syscalls.c
+++ b/arch/um/sys-i386/syscalls.c
@@ -69,15 +69,11 @@ long sys_clone(unsigned long clone_flags, unsigned long newsp,
 {
         long ret;
 
-        /* XXX: normal arch do here this pass, and also pass the regs to
-         * do_fork, instead of NULL. Currently the arch-independent code
-         * ignores these values, while the UML code (actually it's
-         * copy_thread) does the right thing. But this should change,
-         probably. */
-        /*if (!newsp)
-                newsp = UPT_SP(current->thread.regs);*/
+        if (!newsp)
+                newsp = UPT_SP(&current->thread.regs.regs);
         current->thread.forking = 1;
-        ret = do_fork(clone_flags, newsp, NULL, 0, parent_tid, child_tid);
+        ret = do_fork(clone_flags, newsp, &current->thread.regs, 0, parent_tid,
+                      child_tid);
         current->thread.forking = 0;
         return(ret);
 }
@@ -197,14 +193,3 @@ long sys_sigaction(int sig, const struct old_sigaction __user *act,
 
         return ret;
 }
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/sys-x86_64/syscalls.c b/arch/um/sys-x86_64/syscalls.c
index 6f44f40204ed..3259a4db4534 100644
--- a/arch/um/sys-x86_64/syscalls.c
+++ b/arch/um/sys-x86_64/syscalls.c
@@ -174,26 +174,11 @@ long sys_clone(unsigned long clone_flags, unsigned long newsp,
 {
         long ret;
 
-        /* XXX: normal arch do here this pass, and also pass the regs to
-         * do_fork, instead of NULL. Currently the arch-independent code
-         * ignores these values, while the UML code (actually it's
-         * copy_thread) does the right thing. But this should change,
-         probably. */
-        /*if (!newsp)
-                newsp = UPT_SP(current->thread.regs);*/
+        if (!newsp)
+                newsp = UPT_SP(&current->thread.regs.regs);
         current->thread.forking = 1;
-        ret = do_fork(clone_flags, newsp, NULL, 0, parent_tid, child_tid);
+        ret = do_fork(clone_flags, newsp, &current->thread.regs, 0, parent_tid,
+                      child_tid);
         current->thread.forking = 0;
         return(ret);
 }
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */