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

From: Andrew Morton
Date: Thu Jul 19 2007 - 20:42:54 EST


On Sun, 8 Jul 2007 22:55:08 -0300
Diego Woitasen <diego@xxxxxxxxxxxxxxx> wrote:

> Signed-off-by: Diego Woitasen <diego@xxxxxxxxxxxxxxx>
> ---
> 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?
-
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