Module Name: src
Committed By: uebayasi
Date: Sat Apr 12 15:08:56 UTC 2014
Modified Files:
src/sys/kern: kern_exec.c
Log Message:
execve_runproc: Correct thinko in Rev. 1.386; the new SP always points to
after (higher adderss) argc/argv/env/aux/strings regardless of stack growing
direction . Machines with grow-up stack will detect the top of
argc/argv/env/aux/strings by the address of *argv[] via ps_strings:ps_argvstr.
This means that old comments about RTLD_GAP are all obsolete.
With help from Nick Hudson.
To generate a diff of this commit:
cvs rdiff -u -r1.389 -r1.390 src/sys/kern/kern_exec.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/kern_exec.c
diff -u src/sys/kern/kern_exec.c:1.389 src/sys/kern/kern_exec.c:1.390
--- src/sys/kern/kern_exec.c:1.389 Sat Apr 12 07:38:32 2014
+++ src/sys/kern/kern_exec.c Sat Apr 12 15:08:56 2014
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_exec.c,v 1.389 2014/04/12 07:38:32 uebayasi Exp $ */
+/* $NetBSD: kern_exec.c,v 1.390 2014/04/12 15:08:56 uebayasi Exp $ */
/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -59,7 +59,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.389 2014/04/12 07:38:32 uebayasi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.390 2014/04/12 15:08:56 uebayasi Exp $");
#include "opt_exec.h"
#include "opt_execfmt.h"
@@ -246,7 +246,6 @@ struct execve_data {
int ed_szsigcode;
long ed_argc;
long ed_envc;
- vaddr_t ed_newstack;
};
/*
@@ -1202,9 +1201,6 @@ execve_runproc(struct lwp *l, struct exe
/* Skip a few words reserved for _rtld(). */
stack = STACK_GROW(stack, RTLD_GAP);
- /* Remember the new stack address for setregs(). */
- data->ed_newstack = (vaddr_t)stack;
-
/* Now copy argc, args & environ to the new stack. */
error = (*epp->ep_esch->es_copyargs)(l, epp,
&data->ed_arginfo, &stack, data->ed_argp);
@@ -1308,10 +1304,21 @@ execve_runproc(struct lwp *l, struct exe
doexechooks(p);
- /* setup new registers and do misc. setup. */
- (*epp->ep_esch->es_emul->e_setregs)(l, epp, data->ed_newstack);
+ {
+ /*
+ * Set initial SP at the top of the stack.
+ *
+ * Note that on machines where stack grows up (e.g. hppa), SP points to
+ * the end of arg/env strings. Userland guesses the address of argc
+ * via ps_strings::ps_argvstr.
+ */
+ const vaddr_t newstack = (vaddr_t)STACK_GROW(vm->vm_minsaddr, epp->ep_ssize);
+
+ /* Setup new registers and do misc. setup. */
+ (*epp->ep_esch->es_emul->e_setregs)(l, epp, newstack);
if (epp->ep_esch->es_setregs)
- (*epp->ep_esch->es_setregs)(l, epp, data->ed_newstack);
+ (*epp->ep_esch->es_setregs)(l, epp, newstack);
+ }
/* Provide a consistent LWP private setting */
(void)lwp_setprivate(l, NULL);
