[PATCH v2 1/5] KVM: selftests: Remove address rounding in guest code

From: Ben Gardon <bgardon@google.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	linux-kselftest@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>, Peter Xu <peterx@redhat.com>,
	Andrew Jones <drjones@redhat.com>,
	Peter Shier <pshier@google.com>,
	Sean Christopherson <sean.j.christopherson@intel.com>,
	Thomas Huth <thuth@redhat.com>, Peter Feiner <pfeiner@google.com>,
	Ben Gardon <bgardon@google.com>
Subject: [PATCH v2 1/5] KVM: selftests: Remove address rounding in guest code
Date: Tue,  3 Nov 2020 15:49:48 -0800	[thread overview]
Message-ID: <20201103234952.1626730-2-bgardon@google.com> (raw)
In-Reply-To: <20201103234952.1626730-1-bgardon@google.com>

Rounding the address the guest writes to a host page boundary
will only have an effect if the host page size is larger than the guest
page size, but in that case the guest write would still go to the same
host page. There's no reason to round the address down, so remove the
rounding to simplify the demand paging test.

Signed-off-by: Ben Gardon <bgardon@google.com>
---
 tools/testing/selftests/kvm/demand_paging_test.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
index 360cd3ea4cd67..32a42eafc6b5c 100644
--- a/tools/testing/selftests/kvm/demand_paging_test.c
+++ b/tools/testing/selftests/kvm/demand_paging_test.c
@@ -103,7 +103,6 @@ static void guest_code(uint32_t vcpu_id)
 	for (i = 0; i < pages; i++) {
 		uint64_t addr = gva + (i * guest_page_size);
 
-		addr &= ~(host_page_size - 1);
 		*(uint64_t *)addr = 0x0123456789ABCDEF;
 	}
 
-- 
2.29.1.341.ge80a0c044ae-goog

