From: David Stevens <stevensd@xxxxxxxxxxxx> hva_to_pfn() includes a check that KVM isn't trying to do an async page fault in a situation where it can't sleep. Downgrade this check from a BUG_ON() to a WARN_ON_ONCE(), since DoS'ing the guest (at worst) is better than bringing down the host. Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx> Signed-off-by: David Stevens <stevensd@xxxxxxxxxxxx> --- virt/kvm/kvm_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c5e4bf7c48f9..6f37d56fb2fc 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2979,7 +2979,7 @@ kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool interruptible, int npages, r; /* we can do it either atomically or asynchronously, not both */ - BUG_ON(atomic && async); + WARN_ON_ONCE(atomic && async); if (hva_to_pfn_fast(addr, write_fault, writable, &pfn)) return pfn; -- 2.44.0.rc1.240.g4c46232300-goog
