Commit ca3f0874 authored Apr 08, 2015 by Radim Krčmář Committed by Paolo Bonzini Apr 10, 2015

KVM: use slowpath for cross page cached accesses



kvm_write_guest_cached() does not mark all written pages as dirty and
code comments in kvm_gfn_to_hva_cache_init() talk about NULL memslot
with cross page accesses.  Fix all the easy way.

The check is '<= 1' to have the same result for 'len = 0' cache anywhere
in the page.  (nr_pages_needed is 0 on page boundary.)

Fixes: 8f964525 ("KVM: Allow cross page reads and writes from cached translations.")
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Message-Id: <20150408121648.GA3519@potion.brq.redhat.com>
Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 3ea3b7fa

virt/kvm/kvm_main.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1637,8 +1637,8 @@ int kvm_gfn_to_hva_cache_init(struct kvm kvm, struct gfn_to_hva_cache ghc,
		ghc->generation = slots->generation;
		ghc->len = len;
		ghc->memslot = gfn_to_memslot(kvm, start_gfn);
		ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, &nr_pages_avail);
		if (!kvm_is_error_hva(ghc->hva) && nr_pages_avail >= nr_pages_needed) {
		ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, NULL);
		if (!kvm_is_error_hva(ghc->hva) && nr_pages_needed <= 1) {
		ghc->hva += offset;
		} else {
		/*

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