Re: [PATCH] Use the tsk argument in init_new_context()

[Andrew Morton <akpm@linux-foundation.org>]

On Sun,  8 Jul 2007 22:55:08 -0300
Diego Woitasen <diego@woitasen.com.ar> wrote:

> Signed-off-by: Diego Woitasen <diego@woitasen.com.ar>
> ---
>  arch/i386/kernel/ldt.c   |    2 +-
>  arch/x86_64/kernel/ldt.c |    2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/i386/kernel/ldt.c b/arch/i386/kernel/ldt.c
> index e0b2d17..c2eb4fb 100644
> --- a/arch/i386/kernel/ldt.c
> +++ b/arch/i386/kernel/ldt.c
> @@ -96,7 +96,7 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
>  
>  	init_MUTEX(&mm->context.sem);
>  	mm->context.size = 0;
> -	old_mm = current->mm;
> +	old_mm = tsk->mm;
>  	if (old_mm && old_mm->context.size > 0) {
>  		down(&old_mm->context.sem);
>  		retval = copy_ldt(&mm->context, &old_mm->context);
> diff --git a/arch/x86_64/kernel/ldt.c b/arch/x86_64/kernel/ldt.c
> index bc9ffd5..99a92ed 100644
> --- a/arch/x86_64/kernel/ldt.c
> +++ b/arch/x86_64/kernel/ldt.c
> @@ -100,7 +100,7 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
>  
>  	init_MUTEX(&mm->context.sem);
>  	mm->context.size = 0;
> -	old_mm = current->mm;
> +	old_mm = tsk->mm;
>  	if (old_mm && old_mm->context.size > 0) {
>  		down(&old_mm->context.sem);
>  		retval = copy_ldt(&mm->context, &old_mm->context);


When called from dup_mm(), `tsk' refers to the new task and `current'
refers to the old one.  I'd have expected this to crash during your testing?