On Wed, 2012-12-19 at 19:01 -0800, Michel Lespinasse wrote: > Hi Simon, > > On Wed, Dec 19, 2012 at 5:56 PM, Simon Jeons <simon.je...@gmail.com> wrote: > > One question. > > > > I found that mainly callsite of expand_stack() is #PF, but it holds > > mmap_sem each time before call expand_stack(), how can hold a *shared* > > mmap_sem happen? > > the #PF handler calls down_read(&mm->mmap_sem) before calling expand_stack. > > I think I'm just confusing you with my terminology; shared lock == > read lock == several readers might hold it at once (I'd say they share > it)
Sorry for my late response. Since expand_stack() will modify vma, then why hold a read lock here? > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
