[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH] x86/shadow: sh_type_to_size[] needs L2H entry when HVM+PV32
- To: Jan Beulich <jbeulich@xxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
- From: Andrew Cooper <Andrew.Cooper3@xxxxxxxxxx>
- Date: Mon, 23 Jan 2023 10:43:50 +0000
- Accept-language: en-GB, en-US
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=citrix.com; dmarc=pass action=none header.from=citrix.com; dkim=pass header.d=citrix.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=91VWZdwQoisjKS1gHEo+DOPoUz9Y4vKhU2F7no2seCA=; b=mXtZ4STtMR6oxF2YUH6cucRcMyQVuNBMjRbTKtZS+1i5+2oxcRjPCMzzBeZM54Po7319PuYdzoEiatCkABvzCBgJq5oVh0vsQq8UfhMVKh4COqyJ9OAbq7JJ4yVXGiPjQ2OdGh3a07r6akLZjBeDl/uVe79sZAWvKjeZg3kpVpQeXYicVXMmpt3Fy3wSMhJYwjOR4/wlinmD1Quk8mvU1POVgiscFWTfjHltfsAJY1heJwAwSMp34r/c6f+0Y/IIjm7yaH8eYey0EzYwl/SDZd8sfVwOlRJzhmeWu3WDNNBu22uM6qjhjm/MYxvpvyfyJuI4KbzUV6erAk1scWXh8Q==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=la01BiyxY/6+sl0I+xmlKtrwbtSVWBj00n6nD4a6XJzL6sfJBiZGcjhmcgh1uJTU93IOXJEGoQtzxq8Ewa9kFkeDq+TafasSX9J7MmYEPp7rOSwtfquJrcHY7xibNOHdDv+mO/ucnnNfvovSNopSCqa0TXuLj5wKCxWiBYVmnO110vQRqArE2xq1B1fuWm66KNDLPXy1rvYOjJGOHUys3CV+c51K/FZTHKDz6cjnkkbFbqDlFR9lrczVxeAdIXVbpGcVVJBv2NQk3xYvVRXKkyoqAmRlsTeY3cKualnzFQ/Ho4qK8oGZHyiVoErBDVzO+fDfAt/59/rrphDCyqgBEA==
- Authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=citrix.com;
- Cc: Wei Liu <wl@xxxxxxx>, Roger Pau Monne <roger.pau@xxxxxxxxxx>, "Tim (Xen.org)" <tim@xxxxxxx>, George Dunlap <George.Dunlap@xxxxxxxxxx>
- Delivery-date: Mon, 23 Jan 2023 10:44:00 +0000
- Ironport-data: A9a23:LzQCjqkHVOShhKe+j1G4ZB/o5gywJ0RdPkR7XQ2eYbSJt1+Wr1Gzt xJOUTqEPvaKMDT8etp1YIzg/RgC65PTytQ1GlBu/y42QSMWpZLJC+rCIxarNUt+DCFhoGFPt JxCN4aafKjYaleG+39B55C49SEUOZmgH+a6U6icf3grHmeIcQ954Tp7gek1n4V0ttawBgKJq LvartbWfVSowFaYCEpNg064gE4p7auaVA8w5ARkPqgS5gSGzhH5MbpETU2PByqgKmVrNrbSq 9brlNmR4m7f9hExPdKp+p6TnpoiG+O60aCm0xK6aoD66vRwjnVaPpUTbZLwXXx/mTSR9+2d/ f0W3XCGpaXFCYWX8AgVe0Ew/yiTpsSq8pefSZS0mZT7I0Er7xIAahihZa07FdRwxwp5PY1B3 ecAIyETST2Hu8b1x+jja8lrlPwnLPC+aevzulk4pd3YJdAPZMmaBonvu5pf1jp2gd1SF/HDY cZfcSBocBnLfxxIPBEQFY46m+CrwHL4dlW0qnrM/fZxvzeVkVM3iee1WDbWUoXiqcF9t0CUv G/ZuU/+BQkXLoe3wjuZ6HO8wOTImEsXXapDT+fjp6E00TV/wEQyUiRKWF+5j8Cmg02yQ8hZN FE2pXoH+P1aGEuDC4OVsweDiHyOswMYWtFQO/Yn8wzLwa3Riy6JC25BQjNfZdgOsM4tWSdsx lKPh8nuBzFkrPuSU3313qiQhSO/P24SN2BqTTMFSCMV7t+lp5s85i8jVf5mGa+xy9HwRzf5x mnTqDBk3upLy8kWy6+84FbLxSq2oYTERRI04QORWX+56gR+Z8iuYInABUXn0Mus5b2xFjGp1 EXoUeDHhAzSJflhTBCwfdg=
- Ironport-hdrordr: A9a23:5Ws0zq5LufYSgVDfmAPXwMzXdLJyesId70hD6qkmc20wTiX4ra CTdZsgviMc5Ax6ZJhCo7G90cu7Lk80rqQFhLX5VI3KNDUO3lHEEGgI1+XfKlPbdxEXWYRmpM BdmwQVMqySMbDa5/yKgjWFLw==
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
- Thread-index: AQHZLwKEbZ+pvxq41k6VhQDqg2rUMq6r0SKA
- Thread-topic: [PATCH] x86/shadow: sh_type_to_size[] needs L2H entry when HVM+PV32
On 23/01/2023 8:12 am, Jan Beulich wrote:
> While the table is used only when HVM=y, the table entry of course needs
> to be properly populated when also PV32=y. Fully removing the table
> entry we therefore wrong.
>
> Fixes: 1894049fa283 ("x86/shadow: L2H shadow type is PV32-only")
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Erm, why?
The safety justification for the original patch was that this is HVM
only code. And it really is HVM only code - it's genuinely compiled out
for !HVM builds.
So if putting this entry back in fixes the regression OSSTest
identified, then either SH_type_l2h_64_shadow isn't PV32-only, or we
have PV guests entering HVM-only logic. Either way, the precondition
for correctness of the original patch is violated, and it needs
reverting on those grounds alone.
~Andrew
|
