On Tue, Nov 12, 2024 at 9:08 PM Hugh Dickins <hughd@xxxxxxxxxx> wrote: > > On Tue, 12 Nov 2024, Suren Baghdasaryan wrote: > > > > Thinking about this some more, I don't think this works. I'm relying > > on vma_start_read() to stabilize the vma, however the lock I'm taking > > is part of the vma which can be reused from under us. So, the lock I'm > > taking might be reinitialized after I take the lock... > > I need to figure out a way to stabilize the vma in some other manner > > before taking this lock. > > (I'm not paying attention and following the patches, I just happened > to notice this remark: forgive me if I'm out of context and have > misunderstood, but hope this might help:) > > But this is exactly the problem SLAB_TYPESAFE_BY_RCU was invented for. > You just have to be careful that the locks are initialized only when the > slab is first created (allocated from buddy), not reinitialized whenever > a new object is allocated from that slab. Hi Hugh! I'm looking into SLAB_TYPESAFE_BY_RCU implementation and trying to figure out if initializing the lock in the ctor() of the cache as mentioned in the comment here: https://elixir.bootlin.com/linux/v6.12-rc7/source/include/linux/slab.h#L127 would help my case. I assume that's what you are hinting here? > > Hugh
