Commit 1e38c126 authored by David S. Miller's avatar David S. Miller
Browse files

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: default avatarDavid S. Miller <davem@davemloft.net>
parent 58163393

arch/sparc/kernel/process.c

+16 −4
Original line number Diff line number Diff line
@@ -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,

	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

arch/sparc64/kernel/process.c

+15 −3
Original line number Diff line number Diff line
@@ -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,

	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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