On Tue, Mar 26, 2024 at 04:24:01PM -0600, Jens Axboe wrote:
> On 3/26/24 3:25 PM, Jens Axboe wrote:
> > diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> > index 22aa63f4ef63..26a69fa6809c 100644
> > --- a/mm/vmalloc.c
> > +++ b/mm/vmalloc.c
> > @@ -1032,7 +1032,7 @@ find_vmap_area_exceed_addr_lock(unsigned long addr, struct vmap_area **va)
> > for (i = 0; i < nr_vmap_nodes; i++) {
> > vn = &vmap_nodes[i];
> >
> > - spin_lock(&vn->busy.lock);
> > + spin_lock_nested(&vn->busy.lock, i);
> > va_lowest = __find_vmap_area_exceed_addr(addr, &vn->busy.root);
> > if (va_lowest) {
> > if (!va_node || va_lowest->va_start < (*va)->va_start) {
>
> Omar said he tested this and ran into lockdep complaining as it only
> supports 8 subclasses. So this patch can't work, but that still leaves
> the current kernel code buggy...
>
It is a bit tricky. Let me rewrite it so a lockdep does not complain.
Thank you for your report.
--
Uladzislau Rezki
