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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?tAZJE/hBFb7jm43hJb1Yo/KGbL5BZ/QnWXxWERsridEMuAwpq0zcGQuy4pQf?= =?us-ascii?Q?dkTtir9BvnrBvI/FdGeEgI10Ap9YpqxpNk/dC058eR2m8iDvMLHZs4xv/i3r?= =?us-ascii?Q?V3bGjA2NNPT3DIsNM14NO1kMmcXd9goQyBq/0IySNI/c+B9tUrUrqzYpmZqJ?= =?us-ascii?Q?pY9Sul2xCgv8EheuxENbrmUT7HelU0OKQB13fzK5JrF0nbsu14CoUPGQO2JD?= =?us-ascii?Q?xTswn3NaOjBggO77KrECWB1oSDistoS4YZ/oDsCqiYad0Pxkx65hrCck2zuI?= =?us-ascii?Q?ucSKWnWDJCZt+JEIwtqmLCfeopKOgk3vBsryygza2T2sU/QD7rwaUUO+uUqp?= =?us-ascii?Q?wmTDInvhVs8CIF+ByZoHgbWEyz+2hqyJVx21xFA+s7lsecPKI6I18+7eyRks?= =?us-ascii?Q?tcMP4moKN/gcP7s8ztnhEbgoCQjB0NJXZWk4H6LIlYY4HeqNIDx5LC0DMvkp?= =?us-ascii?Q?aJtWfWMirNS8+8CZyqH3joByyv40djupkg5jTH9/nmdglfpJYbxznEvHq7j7?= =?us-ascii?Q?M3NbXtyQHEZi0WWdXLk7+O7ykBqGVd28+qmy/oDkOpJEByvPCXa9EvTemhat?= =?us-ascii?Q?pxYPBI7kzDqnI27jTXgn+SYfoi8NdZ2LJUvSEhqmBYCXhItslAFX0ZefK9mH?= =?us-ascii?Q?QVyaiPdn5v3KRvLHvK6glBZZ2NgQ9EYg4MR91gMsmbfF1CYOxS//bAJXJJwh?= =?us-ascii?Q?ULEcR32JuIsSHk6BQPeEDQbfZMnxl6wWIx6Iju5OKXMjGT3ezqnThEV/e3a7?= =?us-ascii?Q?lKz8OBV7s46lcVsX8U4PVT5azbzk1/+tGr7aU4nldYsBT1upn3urxBOOLfAY?= =?us-ascii?Q?q7X2RIwVYUxyoq5Y0lBhM1glpVliukruzjiIw8JMv81bkA7Ej+GWOW5wV4T+?= =?us-ascii?Q?K+91VJx2vDB/nfl83o0FlF3HblDfDakjg+bsv/3NdS0Tupj549cxcPaxVsmj?= =?us-ascii?Q?V47NhGbXmVT1om6eVi1R/AOfhuq/+e766NxBvT7IMS8iUPWeQws3+ofH0y4M?= =?us-ascii?Q?PtRuqWpZpWXoZ8++xDiiDhMyXBFaMvzKTIP3ynedaMcyt09e7vxNa5tz5RtZ?= =?us-ascii?Q?fdjgJ8/VQD/GB4fZMqKXPKGv+igjUIRNlLBSYD90i5e88yNXuNRjye2ANFY3?= =?us-ascii?Q?p/draOXpFhUaAwQs+eU/ewX3u6sHhnu+kPTB2kVVDBRY5mkLle4Ilb2xKbuz?= =?us-ascii?Q?/+5cbKtQzlrXIZSCLsrgOD3qxbVjN1dAATpQqATv7VFR3Aip7L9sQO8MtO3u?= =?us-ascii?Q?cg7Gqldvysznx9ZVLsFzn909jZOPbaHEFLC/0U4HfBpCWs/GEfAy6Xxfd5d4?= =?us-ascii?Q?lFV8debU/pr8BJDmSND7uqqhj48kTZoAXrEMheF6tB1kK4FIoB4EonScN6xG?= =?us-ascii?Q?R+TXOV0ZL+gCl9EGQORbaszxVmHJizdTMvkuzBUGr07T84Xb3Y+kbrks0sMy?= =?us-ascii?Q?1i74MpRHeam95qwffCfk5w69BPpyF9Z3CbN63+6lrNF9fhTBHRJT0KUjo+8J?= =?us-ascii?Q?M+zsPEt0U05VIMigf3Y/phPJGeangKmL3O2HM9u4vqIf73mti2BoE8Z5/aEC?= =?us-ascii?Q?kWSix8WjM4CrN0jH//XshWDH0/54Y9VeeZK+ORxgPx23KXswFi3nleUt7+no?= =?us-ascii?Q?8FndL8P1wjF1E/PYNjjdBmKIPkDH9wToRLdsfV8+x1mck/00uVC7GM+wU0/9?= =?us-ascii?Q?f5Ajkltv8cltADy15U9Gb3UMkCO4Nyjt0IEGyu61IDUcnYUa?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3adc22e7-50f9-4189-b8c5-08dec6eecf24 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Jun 2026 12:50:11.5637 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: eOPV/EBi/3mSp08ZA8zy6gP0stWJntdrEZhwCg0rwY4OrDG9wWz2cQB21BP5C+Pp X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS2PR12MB9776 On Wed, Jun 10, 2026 at 12:28:33PM +0100, Will Deacon wrote: > > Note: stlr* only supports base-register addressing, so the raw accessors > > can no longer use the offset addressing introduced by commit d044d6ba6f02 > > ("arm64: io: permit offset addressing"). The str* and stlr* alternates > > share a single inline-asm operand and the sequence is selected at boot, > > so the operand form is fixed at compile time; unaffected CPUs keep using > > str* but also revert to base-register addressing. This keeps the store > > side as simple as the existing load-side patching (load-acquire) and > > avoids adding complexity to the device write path; retaining offset > > addressing only for str* would otherwise require a runtime branch on > > every write. > > I seem to remember Jason caring about that, possibly because some CPUs > are very picky about write-combining? I think it was more a fall out of the work there, after looking at the assembly this minor edit to the constraint made a nice codegen impact. It is certainly a shame to loose it for this bug. If we care about write combining we can't have a branch anyhow, but that is most important for the specific memcpy operations (which will need a branch) Jason