From 1e38c126c9252b612697e34f43b1b3371c8ee31d Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 7 May 2008 16:21:28 -0700 Subject: [PATCH] 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 --- arch/sparc/kernel/process.c | 20 ++++++++++++++++---- arch/sparc64/kernel/process.c | 18 +++++++++++++++--- 2 files changed, 31 insertions(+), 7 deletions(-) diff --git a/arch/sparc/kernel/process.c b/arch/sparc/kernel/process.c index e7f35198ae3..36431f377de 100644 --- a/arch/sparc/kernel/process.c +++ b/arch/sparc/kernel/process.c @@ -419,14 +419,26 @@ asmlinkage int sparc_do_fork(unsigned long clone_flags, unsigned long stack_size) { unsigned long parent_tid_ptr, child_tid_ptr; + unsigned long orig_i1 = regs->u_regs[UREG_I1]; + long ret; parent_tid_ptr = regs->u_regs[UREG_I2]; child_tid_ptr = regs->u_regs[UREG_I4]; - return do_fork(clone_flags, stack_start, - regs, stack_size, - (int __user *) parent_tid_ptr, - (int __user *) child_tid_ptr); + ret = do_fork(clone_flags, stack_start, + regs, stack_size, + (int __user *) parent_tid_ptr, + (int __user *) 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 diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c index 500ac6d483a..4129c044985 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 -- 2.41.1