From 943dfea8f166d62657057170dbe8667ec96247ca Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Fri, 29 Apr 2022 01:04:07 +0000 Subject: KVM: Do not zero initialize 'pfn' in hva_to_pfn() Drop the unnecessary initialization of the local 'pfn' variable in hva_to_pfn(). First and foremost, '0' is not an invalid pfn, it's a perfectly valid pfn on most architectures. I.e. if hva_to_pfn() were to return an "uninitializd" pfn, it would actually be interpeted as a legal pfn by most callers. Second, hva_to_pfn() can't return an uninitialized pfn as hva_to_pfn() explicitly sets pfn to an error value (or returns an error value directly) if a helper returns failure, and all helpers set the pfn on success. The zeroing of 'pfn' was introduced by commit 2fc843117d64 ("KVM: reorganize hva_to_pfn"), probably to avoid "uninitialized variable" warnings on statements that return pfn. However, no compiler seems to produce them, making the initialization unnecessary. Signed-off-by: Sean Christopherson Message-Id: <20220429010416.2788472-2-seanjc@google.com> Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 04196096f9e4..5b8ae83e09d7 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2609,7 +2609,7 @@ kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, bool write_fault, bool *writable) { struct vm_area_struct *vma; - kvm_pfn_t pfn = 0; + kvm_pfn_t pfn; int npages, r; /* we can do it either atomically or asynchronously, not both */ -- cgit v1.2.3