From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=xen.org header.i=@xen.org header.b="BrFgap+s" Received: from mail.xenproject.org (mail.xenproject.org [104.130.215.37]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7DFD12A; Tue, 21 Nov 2023 10:03:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:MIME-Version:Message-Id:Date: Subject:To:From; bh=ApY+rn3G/nOW/ld6052bD3LXs+qXCXswGYK8qsPr9M8=; b=BrFgap+sw l2nTXG3eNcovUHWIq/QdZUWWLOEwzARgJIvGAzWfqKdh4cm6B1E17W8e7MKOKhSPGiraP/271NlZh JXk25UAl6JubDkoZMMgMi5Jd7ydqCskLs5XMcxJkwFJSPSsqtgQlHCCxSmfojKgpFjkhpr/mfDp9Q 4ILkQ9iU=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1r5V5D-00083I-Cg; Tue, 21 Nov 2023 18:02:47 +0000 Received: from 54-240-197-231.amazon.com ([54.240.197.231] helo=REM-PW02S00X.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1r5V5D-0004Z3-1u; Tue, 21 Nov 2023 18:02:47 +0000 From: Paul Durrant To: David Woodhouse , Paul Durrant , Sean Christopherson , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v8 00/15] KVM: xen: update shared_info and vcpu_info handling Date: Tue, 21 Nov 2023 18:02:08 +0000 Message-Id: <20231121180223.12484-1-paul@xen.org> X-Mailer: git-send-email 2.39.2 Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Paul Durrant Currently the shared_info page is treated as guest memory and the VMM informs KVM of its location using a GFN. However it is not guest memory as such; it's an overlay page. So the pfncache is pointlessly invalidated and re-activated to create a new mapping of the *same page* of memory every time the guest requests that shared_info be mapped into its address space. Avoid doing that by modifying the pfncache code to allow activation using a fixed userspace HVA as well as a GPA. Version 8 of the series has been substantially re-worked and includes several clean-up patches, particlarly the non-trivial clean-up patches: "pfncache: remove KVM_GUEST_USES_PFN usage" and "xen: split up kvm_xen_set_evtchn_fast()". Each patch carries its own version history. Paul Durrant (15): KVM: pfncache: Add a map helper function KVM: pfncache: remove unnecessary exports KVM: xen: mark guest pages dirty with the pfncache lock held KVM: pfncache: add a mark-dirty helper KVM: pfncache: remove KVM_GUEST_USES_PFN usage KVM: pfncache: stop open-coding offset_in_page() KVM: pfncache: include page offset in uhva and use it consistently KVM: pfncache: allow a cache to be activated with a fixed (userspace) HVA KVM: xen: allow shared_info to be mapped by fixed HVA KVM: xen: allow vcpu_info to be mapped by fixed HVA KVM: selftests / xen: map shared_info using HVA rather than GFN KVM: selftests / xen: re-map vcpu_info using HVA rather than GPA KVM: xen: advertize the KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA capability KVM: xen: split up kvm_xen_set_evtchn_fast() KVM: xen: allow vcpu_info content to be 'safely' copied Documentation/virt/kvm/api.rst | 53 +++- arch/x86/kvm/x86.c | 7 +- arch/x86/kvm/xen.c | 260 +++++++++++------- include/linux/kvm_host.h | 38 ++- include/linux/kvm_types.h | 8 - include/uapi/linux/kvm.h | 9 +- .../selftests/kvm/x86_64/xen_shinfo_test.c | 59 +++- virt/kvm/pfncache.c | 175 ++++++------ 8 files changed, 374 insertions(+), 235 deletions(-) base-commit: 45b890f7689eb0aba454fc5831d2d79763781677 --- Cc: Borislav Petkov Cc: Dave Hansen Cc: David Woodhouse Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Paolo Bonzini Cc: Sean Christopherson Cc: Thomas Gleixner Cc: x86@kernel.org -- 2.39.2