Re: [PATCH 1/4] KVM: x86/mmu: Fix RCU usage in handle_removed_tdp_mmu_page

From: Sean Christopherson
Date: Fri Mar 12 2021 - 10:38:46 EST


On Thu, Mar 11, 2021, Ben Gardon wrote:
> The pt passed into handle_removed_tdp_mmu_page does not need RCU
> protection, as it is not at any risk of being freed by another thread at
> that point. However, the implicit cast from tdp_sptep_t to u64 * dropped
> the __rcu annotation without a proper rcu_derefrence. Fix this by
> passing the pt as a tdp_ptep_t and then rcu_dereferencing it in
> the function.
>
> Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>

Should be <lkp@xxxxxxxxx>. Looks like you've been taking pointers from Paolo :-)

https://lkml.org/lkml/2019/6/17/1210

Other than that,

Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>

> Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx>