David Teigland writes:
if (!dumping)
down_read(&mm->mmap_sem);
> > +
> > + for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
> > + if (end <= vma->vm_start)
> > + break;
> > + if (vma->vm_file &&
> > + vma->vm_file->f_dentry->d_inode->i_sb == sb) {
> > + num_gh++;
> > + }
> > + }
> > +
> > + ghs = kmalloc((num_gh + 1) * sizeof(struct gfs2_holder),
> > + GFP_KERNEL);
> > + if (!ghs) {
> > + if (!dumping)
> > + up_read(&mm->mmap_sem);
> > + return -ENOMEM;
> > + }
> > +
> > + for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
>
> Sorry if this is an obvious question but what prevents another thread from
> doing mmap() before we do the second walk and messing up num_gh?
mm->mmap_sem ?
Aah, I read that !dumping expression the other way around. Sorry and thanks.
Pekka
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