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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?8YNE1HUwZjubwLwZyQkvzyFTLN1ABJHIdHuI+POXynoxGbE2Rxmxv3Q1wbVN?= =?us-ascii?Q?6Gp4iowAClpwKNhRyWTGQvvXYYfEzBsnkUNb6sUWuKtEw0HbIRVAwHmYTXSQ?= =?us-ascii?Q?nELiQLZionK3w0mpm2m9oeCqgVZdQUsvMf1UWcpYywceAoBquj8NWjbKRNjm?= =?us-ascii?Q?onS4geYQASR4WSsD4Kvvre2S6spchIaLOHJP3+a+lyTnswe6iKY3RVocj6zu?= =?us-ascii?Q?zx+pJuE65u0dO4yTLVjpt+OQeULHgPI9lkwUTjgE2IpoxHVKZsGXMl6j6555?= =?us-ascii?Q?PuG5KAS5m1g9FGkydxQsWRFfjVPltb1kRvdzVkkOZrS6ClunJQ87osI+PxMe?= =?us-ascii?Q?ug9aW9d18U0aMj9f/ldJM6iG3RXLRf4lEgGs/2Rezj8xmhogMnUu6ksxfpVr?= =?us-ascii?Q?zvPo0E+DmxBP2EgkZPOp9rrO3aBMI6ObDG/xwxdiRs/PZNY/1jvRpe20c5O7?= =?us-ascii?Q?dttj8a1R5NrhKyhE7XlQn83/67P+OeCyrJ8npYwMEWcxf4GxGLZKHNNYBugD?= =?us-ascii?Q?XeCytS+u1Fjh3OiOmpiDVF987uFiyZ3s9VRXlz8IcwUqrjl/BwOuGVR3JmiV?= =?us-ascii?Q?GP0JPUxpTis8Y8pG6vGRqSPk8V9/1VyemP+5Y7lxL5uFH3tHNya3dTWjnLnt?= =?us-ascii?Q?N6zANn8/k/5XlWLty0VmC8XGoEUOtV5G/8zfjVFcM9BJR9Iveyl2j3N/Qj2b?= =?us-ascii?Q?aWGGVhfi5aZtFU9KRbgiGVWF2IQF3pWI33oSv+vSY9b/ClvLaDo0rtPjNR85?= =?us-ascii?Q?xtdbIAG+FfM14JAK6Dh+uB1g6xM1LzFBlMyoelHEDx3Dbe2mzQFGhsb3rwwu?= =?us-ascii?Q?aiFrIXYwFIZyv4f7/9mJUqhjnrE+w7FhUKDN8a0LwDE16tTOq05sIXZcs1Da?= =?us-ascii?Q?t+YHsIStntg2SFSrIKHavT3rwwltH+Z2gpuZSx4mTKgQNbDSIbc4lgGXs4qN?= =?us-ascii?Q?ldAv3VUBVUlvSkj7rqPmTftvN9CMoWh9A/F6oQVvUKlI9IwSjZ3gyDaJalrU?= =?us-ascii?Q?0ZXHnn7uPQlX++wcAMqi3CkaLkKdFK7UoQlLUjBVLD0y5TNkzeEFNTQjqf0A?= =?us-ascii?Q?/RKlKpCVZMZ6HwKpHLkAeXfWXe5DAxcCn4Y2AGeoLAjcBtI8GCe52rDiJzL1?= =?us-ascii?Q?WdW4+TXqLLTBV4foZq3307x5QaihD9G+WVwFI2U46IAN6NvPM7Pn8x1q2Ot5?= =?us-ascii?Q?60gdBNJfr4KbOvAxXjeBeinRGNU6/yPyo/qJL3kLhTZVmfuOlxIXKHh+cRjg?= =?us-ascii?Q?OA1p8ayrYzkD7vRr60IomNneERX9HCEk2iVqDZHWEyosQ1o+urLiltI6flUC?= =?us-ascii?Q?rAO43GUlC9rfkYKSJl2Dklu4HqTr39+FSgauQCjN4oIifb+cWuxvHXdafXKZ?= =?us-ascii?Q?0usMNrwu9gDjc0NKs4ShmwyisMRRKsxI2ysmV8ap4VNlBXwXWVPSUUn7PdjO?= =?us-ascii?Q?HNOlxOsWBP40XxzOgehM03vQeR59c7cR0EZBsaDHFpzBEkErFM5JNTCEw9+i?= =?us-ascii?Q?ARfaKv+0B7frso5gN9jDmqrB9MWGP8DnYAEGBU4odZd5bYZ2qPAiljYXfCeK?= =?us-ascii?Q?tWBag2Cd/TP856YkF2IVWeZtDEFL1oitvP9Cm2Jn?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 136b2265-84cd-4372-fd81-08ddb3fc3414 X-MS-Exchange-CrossTenant-AuthSource: CYYPR12MB8750.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Jun 2025 15:23:14.5776 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: r0hhnL8LUWXC5mxb1Pv3/ppr9RS9h9o2bD7jT8LEO6F0NiyP0eqtA9ChfZTRiF7exs9Km5EPLaC7efJA/J+gfQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY1PR12MB9625 On 04.06.25 14:56:22, Nathan Fontenot wrote: > On 6/3/2025 6:49 PM, Dave Jiang wrote: > > > > > > On 6/3/25 3:19 PM, Smita Koralahalli wrote: > >> Add a NULL check in is_cxl_region() to prevent potential null pointer > >> dereference if a caller passes a NULL device. This change ensures the > >> function safely returns false instead of triggering undefined behavior > >> when dev is NULL. > > > > Don't think this change is necessary. The code paths should not be hitting any NULL region devices unless it's a programming error. > > I originally added this to the patchset during some initial development to handle possible > NULL dev pointers when updating soft reserve resources, see cxl_region_softreserv_update() > in patch 5/7. > > In the current form of the that routine it appears we shouldn't execute the while loop > if dev is NULL so this could get from the patch set. With the suggested change to use bus_for_each_dev() in patch #5 this patch should be dropped. -Robert