On 19/11/20 15:41, Daniel Vetter wrote:
Both Christoph Hellwig and Jason Gunthorpe suggested that usage of follow_pfn by modules should be locked down more. To do so callers need to be able to pass the mmu_notifier subscription corresponding to the mm_struct to follow_pfn(). This patch does the rote work of doing that in the kvm subsystem. In most places this is solved by passing struct kvm * down the call stacks as an additional parameter, since that contains the mmu_notifier. Compile tested on all affected arch.
It's a bit of a pity, it's making an API more complex (the point of gfn_to_pfn_memslot vs gfn_to_pfn is exactly that you don't need a "struct kvm*" and it's clear that you've already done the lookup into that struct kvm.
But it's not a big deal, and the rationale at least makes sense. So, Acked-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> Paolo