From 1e38c126c9252b612697e34f43b1b3371c8ee31d Mon Sep 17 00:00:00 2001
From: "David S. Miller" <davem@davemloft.net>
Date: Wed, 7 May 2008 16:21:28 -0700
Subject: sparc: Fix fork/clone/vfork system call restart.
We clobber %i1 as well as %i0 for these system calls,
because they give two return values.
Therefore, on error, we have to restore %i1 properly
or else the restart explodes since it uses the wrong
arguments.
This fixes glibc's nptl/tst-eintr1.c testcase.
Signed-off-by: David S. Miller <davem@davemloft.net>
---
arch/sparc64/kernel/process.c | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)
(limited to 'arch/sparc64')
diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c
index 500ac6d..4129c04 100644
--- a/arch/sparc64/kernel/process.c
+++ b/arch/sparc64/kernel/process.c
@@ -503,6 +503,8 @@ asmlinkage long sparc_do_fork(unsigned long clone_flags,
unsigned long stack_size)
{
int __user *parent_tid_ptr, *child_tid_ptr;
+ unsigned long orig_i1 = regs->u_regs[UREG_I1];
+ long ret;
#ifdef CONFIG_COMPAT
if (test_thread_flag(TIF_32BIT)) {
@@ -515,9 +517,19 @@ asmlinkage long sparc_do_fork(unsigned long clone_flags,
child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
}
- return do_fork(clone_flags, stack_start,
- regs, stack_size,
- parent_tid_ptr, child_tid_ptr);
+ ret = do_fork(clone_flags, stack_start,
+ regs, stack_size,
+ parent_tid_ptr, child_tid_ptr);
+
+ /* If we get an error and potentially restart the system
+ * call, we're screwed because copy_thread() clobbered
+ * the parent's %o1. So detect that case and restore it
+ * here.
+ */
+ if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
+ regs->u_regs[UREG_I1] = orig_i1;
+
+ return ret;
}
/* Copy a Sparc thread. The fork() return value conventions
--
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