Messages in this thread | | | Date | Thu, 25 Jun 2009 12:04:13 +0200 | From | Ingo Molnar <> | Subject | Re: [GIT pull] futex fixes for 2.6.31 |
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* Thomas Gleixner <tglx@linutronix.de> wrote:
> On Thu, 25 Jun 2009, Zhang, Yanmin wrote: > > On Wed, 2009-06-24 at 21:48 +0200, Thomas Gleixner wrote: > > > +static int fault_in_user_writeable(u32 __user *uaddr) > > > +{ > > > + int ret = get_user_pages(current, current->mm, (unsigned long)uaddr, > > > + sizeof(*uaddr), 1, 0, NULL, NULL); > > The 4th parameter of get_user_pages means page number. sizeof(*uaddr) is equal to > > 4, so you want 4 pages? > > Grrr. I looked up the prototype of it in include/linux/mm.h: > > int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, > unsigned long start, int len, int write, int force, > struct page **pages, struct vm_area_struct **vmas); > > len == number of pages ! How intutitive. :( > > I guess Linus tripped over it as well. See: > http://lkml.org/lkml/2009/6/21/95
heh, and then i suggested to you to change the '4' to sizeof(u32) ;-)
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