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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?sqvlkIdk1NWgLwh/mnbMLGU2P/3mbXjuWqrksXG9SiJdptbzLW1wgqj4wo3J?= =?us-ascii?Q?EaYMMbYs2ebCVXguU/I2PgRjz/RJZAkTL/k4arBjWMMDS8V77j01PeLif/vK?= =?us-ascii?Q?2Fno+nQXFTX5Y/p7E0hKQabWPnMxTGuyJkF4pOcvRvlbAJub6LWZA0T+Ea2k?= =?us-ascii?Q?eGwIRxOXwhbfUngY+hkMFXfUyiDxKQ5898E+7SCI2CK+sVZgQw0Tu0Efyjio?= =?us-ascii?Q?A9gTv+z0KJJAE3pKkdXyPnoOE8D4w9E+N41O1WlGOmERIUz7IWSN6V5FGZIQ?= =?us-ascii?Q?+VAE7EGhPUJd8vJ145sBZea+WF1DFNM0dnWXuKMtT4KLcVve2oKUsYffpgE0?= =?us-ascii?Q?pbYvIRcNsABRYnbmUyEugquBeBqUvVY83BKAKWmIL86HXTbUomZT0CPLk5zo?= =?us-ascii?Q?Xluxa9nJp4yYAzK1l5Ur6dV/Mc7NqHobvzmLLtyNNcnXIUAAHEi4Kr7R6uWS?= =?us-ascii?Q?ytRtF73SEO5dCv1tF+gorMBFLQHp6ITTgSQ9aKo3EEKGHnocJRTAAEwff4Lr?= =?us-ascii?Q?Y4ZM792zKugmxE+HEx/2Rfg6SlDwjxveDlADP+zYpHCIy0ITn3IPjz4oxiE6?= =?us-ascii?Q?34Jw4gLcSrl+7lvaq/EjZ6RWnAeUMKn1GYFn7LHyhw3bUEX+QNyOo52eh17b?= =?us-ascii?Q?XwzQST1YLzMNGku/9o4GUOvvAtQRgJY7LNYqza+bXsN/H59FEqHFKV9maZKX?= =?us-ascii?Q?zT8rYDPm3O0xwGvWoC51eV3psMWJqIzX8+B7DLskfG57gwKAZna4O85Qli+c?= =?us-ascii?Q?VTw3WhBs9k3PdZB9MHveU5sC6fR9owcqDdYV+V0V9stsdVwxBOFs6VfV2LgW?= =?us-ascii?Q?WagjVAuae/hTYVsEMjgEg+oHtD9b55usCCid6NA7T+G8HGc/8FlpG4PgQU+Z?= =?us-ascii?Q?l2Da2qqlAvk97UA2WUR8F5zhRNYOom5S1dS+qr0yM83yvYvwaPHVSI41hniE?= =?us-ascii?Q?mQ1LmiVV5XLB1BfxMbfOcFFF7o3LYeuNC3CwwAPfaLxVz4UEx9tfIqJqP5X1?= =?us-ascii?Q?3xxuZOp4ApvTm9zyqYgOq3Ymgg1FnzrizdZ1VQBTykT23KcLnbh5Z58qRtEi?= =?us-ascii?Q?Y2rXJ5Ke7lELwvrlQvioVm3ddrpqZSNljPzIZYiNHJE78pP3EqvUGIgcW9bf?= =?us-ascii?Q?DSmV168orY1OeB+/3+iL3SicmEvSqA+4Ep+QrLxhYyISfqdrnJXdT7RTV5e5?= =?us-ascii?Q?K3vvdTKj0J+JfXxshsL8tUknvT9BOEF0EVPq1sCVCglFtTY6li7tGvjzh5RW?= =?us-ascii?Q?1N02noFCnU5qaEoFMtdyh/3zW9oeSSlXOiQsax8OPQIfWR+BvaOufClA5H/U?= =?us-ascii?Q?pcMd0A0oRYBFR8ww+dxv9JAamaCVT7Q1QYDyzMw7dzMUnWTtmxl61UJcwoy6?= =?us-ascii?Q?RjSYkZENJovgKkGJOVRq3w28a8gxqhCmBjMJ+11dpgUiNKJG6OiY2eE3zkrr?= =?us-ascii?Q?HB4posk9HuSx9KiyxYst/C+Y7K7VH15r/o+wu7yMU4isEjAwJT64I1gagdBC?= =?us-ascii?Q?TO6V2QX3jZ5Yi1+1S2km3tzR5Inwimz5+nE4sT8zg7L/db4RxtvEWGiIz68p?= =?us-ascii?Q?Dhx0EBYKWHfrKHn1Mh2QNY6s8ogU9IhLq/m1jXVnnBod6hKNAgGuR1exRnPG?= =?us-ascii?Q?+dbvO8RcI0voth7YepFQJh3HECbuiYHAk8xz602vZg0diByEdTV/K5mC/PT6?= =?us-ascii?Q?6bB3SN9gvHdNL2WRi4unekEuDxO6NTxNsZqoVQvGSuilUBX/8FBsyID9PHp2?= =?us-ascii?Q?vVqetT0QsA=3D=3D?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6812e1a7-e24a-4b01-9065-08da3e236ff3 X-MS-Exchange-CrossTenant-AuthSource: VE1PR04MB6560.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 May 2022 07:51:55.0138 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 8+ydYnSnze/yMs1yXizfXik9HTtePhLg2VOVm4sv79BsgOp3BC88lNUIQ0BXAR8T/bFRTQ99FF8cHMR3dxmD0g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM0PR04MB5105 On 25.05.2022 09:46, Roger Pau Monn=C3=A9 wrote: > On Wed, May 25, 2022 at 09:34:32AM +0200, Jan Beulich wrote: >> On 25.05.2022 09:21, Roger Pau Monn=C3=A9 wrote: >>> On Wed, May 25, 2022 at 08:02:17AM +0200, Jan Beulich wrote: >>>> On 24.05.2022 18:46, Roger Pau Monn=C3=A9 wrote: >>>>> Would you be fine with adding: >>>>> >>>>> Note that FLUSH_FORCE_IPI doesn't need to be handled explicitly, as >>>>> it's main purpose is to prevent the usage of the hypervisor assisted >>>>> flush if available, not to force the sending of an IPI even for cases >>>>> where it won't be sent. >>>> >>>> Hmm, yes, that's even more verbose than I would have expected it to >>>> be. Just one point: I'm not sure about "main" there. Is there really >>>> another purpose? >>> >>> Right, I should remove main. >>> >>>> Of course an alternative would be to rename the flag to properly >>>> express what it's for (e.g. FLUSH_NO_HV_ASSIST). This would then >>>> eliminate the need for a comment, afaic at least. >>> >>> I think it's likely that we also require this flag if we make use of >>> hardware assisted flushes in the future, and hence it would better >>> stay with the current name to avoid renaming in the future. >>> >>> Whether the avoidance of sending the IPI is due to hardware or >>> hypervisor assistance is of no interest to the caller, it only cares >>> to force a real IPI to be sent to remote processors. >> >> Well, then it could still be named FLUSH_NO_ASSIST, since as said >> (and as you look to agree with) there's no IPI being forced in the >> general case. >=20 > That would be fine but I don't think it's OK to do in this patch. >=20 > Could do as a prereq if you want, but we should keep in mind the patch > under discussion is fixing a boot regression, the fact that it > doesn't trigger in osstest is just because there's no hardware with > CET Shadow Stacks support in the colo. Sure - I'll be okay either way, with a preference to the rename over the addition of a comment. Jan