On Wed, 27 May 2015 14:09:31 -0700 Joe Perches <j...@perches.com> wrote:
> > Problems when CONFIG_PREEMPT=n.
> >
> > > + down_read(&mm->mmap_sem);
> > > + vma = find_vma(mm, ip);
> > > + if (vma && vma->vm_file) {
> > > + struct file *f = vma->vm_file;
> > > + char *gfp_buf = (char *)__get_free_page(GFP_KERNEL);
> >
> > We shouldn't assume we can use GFP_KERNEL here. Even if the
> > preempt_count() worked, we might be in a context which requires
> > GFP_NOFS or GFP_NOIO.
>
> This code is basically a copy of the existing print_vma_addr()
> so is that true for all the existing uses too?
Yeah, the current code is pretty junky. But normally print_vma_addr()
should never be called so nobody noticed...
In e8bff74a Ingo did a fiddle to preempt_conditional_sti() which looks
like it will address the CONFIG_PREEMPT=n issue, but only on x86.
--
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/
