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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?jtfzX5KbNx8HM1BVWtKkfBV0E7jd05xy4wp68ltTcW4itTp7AzexAi1S5PG8?= =?us-ascii?Q?kpFaWpLEIK8Fpz065wyR7mpW5Hv12tQ08IwAjxWSaaC6yEvCwBVPT0N8OgZ5?= =?us-ascii?Q?CUiMWY9mIhlDwD+tIi7sXHgD6HiDbboR6qxnKgB7eNZX95YilYjHxJc1vH2D?= =?us-ascii?Q?J7TpXF7REpOyeQSwjQzooUSMfzgn1u/ZvNH7VNsmtW85d1epkotRa0T+lHcF?= =?us-ascii?Q?4e4nFzXr4Di7Qe2wwHHJoRi3Du+9ShKss4EeXEXbYmZ5yPFlt1q85qoFXHnX?= =?us-ascii?Q?xJlrFnSFOm0xMUNlkUj44RSZgBHq9MJGCeZrqT9B4UelQhO+pQyvb8ikyuJq?= =?us-ascii?Q?qK5cO0BV1S4V3O/0fAMoxpZxtujdUJP4cD26HpAgPt1tBAUb+nPaDCmyPkS0?= =?us-ascii?Q?uMv7tMKyueVMW5nR+s9PBtzhtrC5k96Xx8vNFAblMD7X5ShcLMlX0JYVXVJn?= =?us-ascii?Q?uKgCkKXMqMYxoow4JzYcLrafKJ/+pK1w5HxCRZ/6C4nIDKw9qlAPGSpwR1L1?= =?us-ascii?Q?Qqytp7UDVT7HKsnUoBM2vfu0zFLLV997qbisSWR13XvwhgukjAAx5QZ7Wipa?= =?us-ascii?Q?6R1hrZZnzPYBX7Ue1Qnx4v5LeXlwnF1fZUwnUU8mdba8INyRPMTHmqVn3OxS?= =?us-ascii?Q?ZMZcU3R0tGb+ZKl2jTlkcdN3I0HIQ5uHBWCg+nCbzIlvTDU0RkjPGpBkaZtH?= =?us-ascii?Q?onnsaOaN9uQ13XtzreoEQzvlo7IQHhkjCRpxxnTnGblPeDvw2K02jRXoClvG?= =?us-ascii?Q?WpebqDkbw1lgjQjmG3Ji6s3E590pD4O95qCRZLtoLzG8GVqAidv1se6RqtCn?= =?us-ascii?Q?a0a3ecbFAgirnHCFDsJws+gfnsthapmAm35bT2hE4Y7dmohICYe0P+rRP2Bt?= =?us-ascii?Q?wIGsL61lGVZYrl9Ii9VKSdv7uJLqwadIPQe29nowRMmaldpERQ/2wVomU6eE?= =?us-ascii?Q?8Ykbxkw+pp6Z6CzueHUet3QfWbAbcZ5V1ecmIvJbXBNxkm8jve3nQkkhHn1h?= =?us-ascii?Q?oQmC1T59O21UueiGbjZHE/9xj9dfktKhNSr4cS+aVSxf8XH5SvoOA5s5E0yN?= =?us-ascii?Q?qS5zWxmzcCfkjGvGDI2FtZyzOjchFP4wZ+JLe/NsM8IePKk+xpZkM6PP0T3D?= =?us-ascii?Q?MqYkHrCiDr3jhgInuer4SdriRq71FOW6hwc5UIMM3SY1MTGP7CjRNHq5m38C?= =?us-ascii?Q?1vmw1ijlkpLBe2Fpl4f8mK5Zn7wDDoDFOejcpx4jjrn6qUDWtdeejFt0fyCs?= =?us-ascii?Q?rAtMH1QkdJQR9Dw7JqWzlyN425fZm56JUtsYnmZZAHvs8gQOtZGXcTzdPVaY?= =?us-ascii?Q?3sVHzM9yZ2IayRf+GM2wJwTRqJy2oIXzhoEKeIVX/+v8GJcjCeubPer3LcAH?= =?us-ascii?Q?ogo4y7sDmtEIgwfuYldK6k+INBdVymlfVgzyCVJUAHlBN3iVyJyAb+qkE0qR?= =?us-ascii?Q?FCsNhIA8pd25ipljMb+D9tmflDsQXQahkAE0lCvHDBUZ0cQdwDy+NsV+9o8r?= =?us-ascii?Q?G5sIqFhQQ+jLyk5brc7dr7uN4V9FHHCrGl+Z4UXAQg80lsrZaGzK+duKlqQR?= =?us-ascii?Q?EWMi+9eqElOGkvYjwZB9H233QFfanqgijS5g+A+fIcZLI6pPS1Ez9Nwc2TbW?= =?us-ascii?Q?bgLW91ba5CSYceLcs/KAhrOxXxWo/ZY5b8nKLIFV2cjTDu+k5loA5hQ+tLsR?= =?us-ascii?Q?lv7vz+DnLPXtxt/tuyvphyTq4mddHpk/z3WiKo8hIABmqh7o?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 56826787-5d4d-47e9-0764-08de8f35dbbd X-MS-Exchange-CrossTenant-AuthSource: PA4PR04MB9366.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Mar 2026 14:57:41.7386 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: ZK6H+lvNiJGdL+3aIKSY0o4pWTEoKOg/128tf6BgnChH13wh6GPq/mXq4ExIcwacixeMuAmVRA0CGL7N9hu7HQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB6958 On Tue, Mar 31, 2026 at 08:12:23PM +0800, Billy Tsai wrote: > The RING_OPERATION1 register contains multiple bitfields (enqueue, > software dequeue, and IBI dequeue pointers) that are updated from > different contexts. Because these updates are performed via > read-modify-write sequences, concurrent access from process and IRQ > contexts can lead to lost updates. > > Example: > CPU 0 (hci_dma_queue_xfer): reads RING_OPERATION1 (enq=5, deq=2) > CPU 1 (hci_dma_xfer_done): reads RING_OPERATION1 (enq=5, deq=2) Add Adrian Hunter , who add lock at equeue. https://lore.kernel.org/linux-i3c/20260306072451.11131-6-adrian.hunter@intel.com/ Dose above patch fix your problem ? Frank