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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?7RoBf5sPHLwKiTcncIldFsIvsRGoSOFc86ReoY8FWuQ8GY/kTQ55JC2MsPPT?= =?us-ascii?Q?jbVlR1cDId0iqwsM/lIl7onbmnk71ZfBROm5ig7I3Lsuz+qILK5aNRLnhQmP?= =?us-ascii?Q?4rvoY8qQaBlix2YnbLXrhcLgdcvsQxn51M0fFBqguSGXimi34WdEzqjHI6f1?= =?us-ascii?Q?BeBLcJ6Zx1RT2th5Er9/s7M+8pCNLfTK0nw8Wnvw99MYEre+7IvNleMaICNu?= =?us-ascii?Q?l0xz3qkoQX2f8bsmVRr1RUW3Ncz1gCujxwRIpdR0EkFobXhX3lCpEpKcQ3DN?= =?us-ascii?Q?mk6kGp73F3XWlwScdkvaEdnHUroWczX+SailTp0YelH8y+wewOLqR/Tl5DVU?= =?us-ascii?Q?PKciNKUjfcwTCj5fqW0svqdUXO0y1t6seHyrTUynH2mDNyjG0Z+kYWVn6na4?= =?us-ascii?Q?m/5dP+1fFI9C4XMSzOt5A8ZEnve7Fn2/cr6cjTAxStME8c1KJV6uvhhCrC5p?= =?us-ascii?Q?/1y583EVA6zCWq8eP//VSOsMGyj3Uz72rqbytf98rEtWppsZQXPB+X6w+jsy?= =?us-ascii?Q?xUI+meH6gaJ4qKEZC72citbaWvdLb3iJQY0y/atfT2ZdrPjLs6PjJ/wpWqql?= =?us-ascii?Q?HksIwTZKuEKIyjBXPQmMZEmgx6pNIDU+p5Nk02262Gj1FYyhWlzaCJwrii9R?= =?us-ascii?Q?LBM6fh/J/Q4xJY1gwOeSLxNe8r5WcFRfPOGbF9LZX8mPpt+4ZB/XWj97pbGn?= =?us-ascii?Q?G0XJuv3pPJsCL+7qSLCrjYS/UfIlq4RNg/mVHhI8qjsTUBYrIa9g2+52Nfm/?= =?us-ascii?Q?h1krJ2bbKA0Viz7D6OurGlH7s2/OvQFD9Z480GuP0Zr9P+/ww+C6licQpxu4?= =?us-ascii?Q?WrPHaAjeHcM214SeuzAOBaK2i9pW7dtt06yTHgYrsNhNzbXBRdw+HjP0lnbs?= =?us-ascii?Q?0KvM79p+Mtj8M3esm6iY6fijIRMoWRKOiuugS7fMXVUX2vh1BVPTctEEc65o?= =?us-ascii?Q?6Nfgcum0sjoRyP3FglnAhZpLxyjJcETP5VzPCLdPfT0/22WmtdXyjQMt0xKr?= =?us-ascii?Q?2ZbvcHj+CafDbHwegJfEVh1absMH2rPYW1k1/fTiXq6fwQyqxwcM8sGxVnfp?= =?us-ascii?Q?rK/uA+snDZ2hiUvv4ZSTxaH0Wy2ZXhBgvejoI5ZJlTzviPBqNh0aLHLnXD1z?= =?us-ascii?Q?8ArlvBvnEo0b6eKlyjSu66FUgBwknFP2NqocoXrfM64dcGuxFqgOzD6hEg1k?= =?us-ascii?Q?l0AmFd2vX6mXVufLWYbhjyo3Jj7VuG2UhB0xvcO5gcPZaLIvZGdK17ZHb8r1?= =?us-ascii?Q?CsiePupTXQkiIV/cqLr0Zko91lD2nvF0RwYQXHyNsyhGAAGsKGfi/LD7emms?= =?us-ascii?Q?Xn2Yb2ompijWL/eiFHKV/2EH?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: bb0466c6-0b59-45a2-7bb7-08d95684c70f X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Aug 2021 13:44:12.6077 (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: l12RMB7TguUhNWoyOiCalXhVDtYu4laAHnAz7PNnI7PKICzRFTisB0pFIEefxEiFlGMRxMO5wFvTfgFxX6H9Gw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB4848 On 03.08.2021 15:30, Marek Marczykowski-G=C3=B3recki wrote: > On Tue, Aug 03, 2021 at 03:16:14PM +0200, Jan Beulich wrote: >> On 03.08.2021 15:12, Marek Marczykowski-G=C3=B3recki wrote: >>> On Tue, Aug 03, 2021 at 03:06:50PM +0200, Jan Beulich wrote: >>>> On 03.08.2021 15:01, Marek Marczykowski-G=C3=B3recki wrote: >>>>> Ok, then, just setting iommu_intremap=3Dfalse should do the right thi= ng, >>>> >>>> ... if "iommu=3Dforce" is in use (but not otherwise), ... >>> >>> But that's the purpose of iommu=3Dforce, no? >>> With "iommu=3Dforce": strictly require IOMMU >>> Without "iommu=3Dforce": use IOMMU on best-effort basis >>> >>> It makes sense to refuse the boot if intremap is broken in the first >>> case. But also, it makes sense to allow using IOMMU without intremp in >>> the second case. >> >> I agree with both statements. What I disagree with is that the latter >> happens by default (instead of only upon admin override), including >> the case of intremap being unavailable in the first place. >=20 > "upon admin override" - do I read the code right, that iommu=3Dno-intrema= p > will actually achieve this effect? In the case of this quirk - yes, as the call to the checking function is gated by a check of iommu_intremap. But by "admin override" I meant a per-guest attribute, not a host-wide one that isn't explicitly meant to cover all guests. > Will that allow to use IOMMU without > interrupt remapping on a hardware where it's broken? In that case, maybe > at least add this info to the log message? You mean to suggest the use of this option? I'd rather not, to be honest. I don't think options like this should be suggested to be used. I'd prefer if we had less of such options, i.e. if they went away after some initial integration phase. Jan