Avi Kivity <avi@xxxxxxxxxx> wrote: > > It should not be necessary, atomicity of updates to > > memslot->dirty_bitmap, because of RCU updates to the memslot pointer > > (note memslot = gfn_to_memslot(kvm, gfn); in mark_page_dirty). > > > > The order is: > > > > - update page data. > > - grab memslot pointer. > > - set page bit in memslot. > > > > What if both grab the same memslot pointer, but set different bits? (Sorry for my bad wording, that is what I wanted to explain.) There seems to be possible concurrent __set_bit()'s to the same word which will result in bit loss. I was thinking to change the kvm-unit-tests' dirty log test to write to two consecutive pages concurrently. Is this good for debugging this? Takuya -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
