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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?zPCBJeHe4iQ/pmtV/tAk8cBXhj+gYYCWZy3Z0TpYYMjnD66wVGAFv+G9IfLx?= =?us-ascii?Q?FDY/55iGmpa9augmSSMYcImsZfApEwCpDBdurMkv4Gp1PbFXvwGc0QoYYU7q?= =?us-ascii?Q?dj/IRu2seqWbvLNLUBX8lDjRJjjf0wWfcrlqX0VO+TjtQh5SHVhPSUqQbcFr?= =?us-ascii?Q?dbvkdezmhg11UKlX+nk6BLxJuBJEBXGk/paDatxO1YPXhQeH9wdpOTY3Exxb?= =?us-ascii?Q?005u120UKo9ZGm8RhlQuBn4miJkGEwdZKN8Skbzio7yxXzVZQlqmxMELdp5R?= =?us-ascii?Q?900ltbhhBteAAQVDqLCsMgZEEWpdmndkRzrI+T7KUe7+kLLAYziJ/Royx9GV?= =?us-ascii?Q?N0u5BxHreU2N1DXPKUFUVw321jwf/T6H2xqRJ/45YUjbx/OAHB5DupZ3snzB?= =?us-ascii?Q?jLpzz7zFk3WpiEIR780sXC19PRKZhv7eZLcth1cpeNNyHU4ZdKbyFjG2LZrZ?= =?us-ascii?Q?yrPhgbLPGLvseuDCMxnjEJnAqTpUb+/hzBOb7jpu3WaprqTsOlZdGhPL7Tp+?= =?us-ascii?Q?dELCYLyZg7su0YqnKY8/BaVhs4E6fWFV9yzG0qyDxCrMh3ykZj3XxpNAqOJO?= =?us-ascii?Q?NvrklUkiVpVwlaa09fqQICFLY6RTK7cbA0/8CALI7JY27k+bdNf7BHymoD1T?= =?us-ascii?Q?1Gi4lf5e02CYyyCbAWmcnZBWikLBzKGy9Hakd+gqQlpK1vSQtEMMZxxBvZZ5?= =?us-ascii?Q?6tg0YspIoPo0JctEaJnRs0np92nKY9dHqPDH3J2qFfi76fKFeUg3xB7Yejkf?= =?us-ascii?Q?apeibxb8rUq/cmHr5w9piTXwOBuLPhk80cQbkF8++PMTBxDwPcxOEkXVGgv1?= =?us-ascii?Q?ROJPv5oU6EUnEuUWYgSsQiTRxabZqzUmAvEuJCpybf1WGoiC5jLox9bRn5yH?= =?us-ascii?Q?6D9kWGo9EscJbxQSADcIylYDgrKXWv47jzsrJGOORi078wItyuc7JQKhngfS?= =?us-ascii?Q?fu+EkJFVZMtEbNV0t1G47VvVsFQEasoDmRqdn6zNpGF7S62HztBXzqN3Bm3i?= =?us-ascii?Q?LCBe2yeW/3dzrUAp9qURDIuvuSHi2aGkCp8mgWmt3NJkDtBhocETrWKh6q73?= =?us-ascii?Q?pTl+dfYjFbsZbIyE7Aj6HFQl4sq2oXXIpZDxADHaWYYreuj3CZr4wtPKUUsf?= =?us-ascii?Q?wIPMaZKsdplxQpPsuOB5dIn8chxOTCdl39s3rPKRqgxWo6FnVPSr9qa9I33d?= =?us-ascii?Q?9KbJTQ7qlAGZTkgq90938I98+ZEGyU5G6DzmcMXgSJWUoJWwDqWT5x4bLHln?= =?us-ascii?Q?tGR155N6hXr6q3dUcg9luCnLLqYKREEj+bS4OQFal7y0J8S3pxLH3JDmq+Az?= =?us-ascii?Q?n5Wo3WhoU8hUA1srE/H5h9i4AhpLg2rXW7dpGBDjHtOd6AcOhfDCd1co7jxq?= =?us-ascii?Q?IHN/MyQF1oOb7L/kv078kTM0BMLGThOnwcuMAKF+qzUTisamkEUKCiMUjmdE?= =?us-ascii?Q?QrcdzMVFKmiwH0rL2n6rNKeZw+ZfLx7Ljfi29pWbAXeTVgW/p2x9kSRJzaLt?= =?us-ascii?Q?fsZiVbAp/Q3oNVD5FjTM4TLMEskWhIPv7eI30v1zQzO1Mal6zSzu4xwcQefj?= =?us-ascii?Q?ysLuhSl7WtUlsj2zRSs+ejiHCq7DuPKi7fO6aFhH6nnKCmLBUdqeA5N5cOvu?= =?us-ascii?Q?H1Sll7wnOoxZ72WfStnam7gWt2FOyYFSMeqZkwchcat1ABTWQra24W1+aH7f?= =?us-ascii?Q?H46ABn5udAtvKluxqXrlzTarSsqcKR4khgGQLuJbBuBWWTYN?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: bcea04b9-1321-4dc9-668d-08deb028ec06 X-MS-Exchange-CrossTenant-AuthSource: CY1PR12MB9601.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 May 2026 13:18:14.1813 (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: t87DDHW1CegJVlbt5xYX1EzdmdJDETR3q9dvGfuGJL8FR9NoRvJ+Mcr8yn+YJFCP X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB7510 On Mon, May 11, 2026 at 04:16:02PM -0600, Alex Williamson wrote: > Bitfield operations are not atomic, they use a read-modify-write > pattern, therefore we should be careful not to pack bitfields that > can be concurrently updated into the same storage unit. > > The split fields (virq_disabled, bardirty, pm_intx_masked, > pm_runtime_engaged, sriov_pwr_active) are mutated post-init from > contexts that don't serialize against the other writers in the same > storage unit, so a bitfield RMW could drop an adjacent field's > update. The remaining bitfields are touched only during probe or > close where no concurrent writer exists, so they stay packed. > > While reordering, place virq_disabled and bardirty earlier to fill > an existing alignment hole. I feel like a comment is needed here for the various bool groupings 'write locked by XX' or something? Jason