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X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Apr 2023 15:00:54.0031 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 623834ee-6753-4bcb-b9f3-08db401db526 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[63.35.35.123];Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: AM7EUR03FT003.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV2PR08MB8099 Hi Luca, > On 18 Apr 2023, at 16:41, Luca Fancellu wrote: >=20 >=20 >=20 >> On 18 Apr 2023, at 15:38, Bertrand Marquis wr= ote: >>=20 >> Hi Julien, >>=20 >>> On 18 Apr 2023, at 16:25, Julien Grall wrote: >>>=20 >>>=20 >>>=20 >>> On 18/04/2023 14:13, Bertrand Marquis wrote: >>>> Hi Luca, >>>=20 >>> Hi, >>>=20 >>>> On this serie I would like to open a discussion on how to handle the v= ector size >>>> and the corresponding command line / configuration / device tree param= eters. >>>> In general the user must either give a vector size it wants or has a s= olution to >>>> just request the maximum supported size. >>>> In the current implementation if a size bigger than the supported one = is provided: >>>> - we silently disable SVE for dom0 >>>> - we silently disable SVE for dom0less >>>> - we do not create a guest when done through tools >>>> This is not completely coherent and i think we should aim for a cohere= nt behaviour >>>> unless we have arguments for this status. >>>=20 >>> +1. >>>=20 >>>> Is there any good reason to silently disable for Dom0 and dom0less onl= y ? >>>> I see some possible solutions here: >>>> - modify parameter behaviour to use the supported size if parameter is= bigger than >>>> it. This would at least keep SVE enabled if a VM depends on it and cou= ld simplify >>>> some of the handling by using 2048 to use the maximum supported size. >>>=20 >>> My concern with this approach and the third one is the user may take so= me time to realize the problem in the xl.cfg. So... >>=20 >> Good point >>=20 >>>=20 >>>> - coherently stop if the parameter value is not supported (including i= f sve is >>>> not supported) >>>=20 >>> ... this is my preferred approach because it would be clear that the va= lue passed to Xen is bogus. >>=20 >> I agree: we should not silently ignore configuration parameters or try t= o "fix" them. >=20 > Hi Bertrand and Julien, >=20 > Ok I will update the serie to stop the domain creation if the parameter s= upplied is wrong or SVE is not supported by the platform. Thanks Bertrand >=20 >>=20 >> Cheers >> Bertrand