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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?8RgpVhZ+qyt7Yo1jRznVza7Dk+ztE6a/mNiHb4Pk+yDyt/4m4Md9N+OeO4+s?= =?us-ascii?Q?1Rtr5Nn3tD3fWYaaYigNithDiZFrwIYZYxeWCWG/2NsMtYRZUvQhFOTH73Rr?= =?us-ascii?Q?YqUv4GCaVyC8SfmEk4J8HQiXC83uxTasxx3iCswFL7sSwy6wXPkANgBkw4wO?= =?us-ascii?Q?gsZYi3AD2KqnqUvVlQo++0FnOMvSIvLoutdIkFKn3f3EbKIc4claAPLPpSe3?= =?us-ascii?Q?a8ffuyzb65FaDxoIN6m86YPssMn+K/zFQERnMtATO9/FqqYekL2cwDUW5ksT?= =?us-ascii?Q?+R3q7L03ZxuM4oXRJ8mAoMllx5qHi0K3cyMgBfdBF6EdrfoHb8dD3YmZhVmS?= =?us-ascii?Q?Tj9l3MIEtzlveJlSl87LnRPQl03xOaG8CIaPWotGgj067SZRAlZUxpytZsTn?= =?us-ascii?Q?KV2tHg4KHkPdwFX1HgwyAgz+Y1G5+j/kEvUfb8cuhASYUCPzhx31q1h0cqU4?= =?us-ascii?Q?wt2Y5BK35IAr02wZEfzqfI6DFULje57B2KZQ4WVrz3NATF1w9LNwW7k/LYA7?= =?us-ascii?Q?j5oSQKKEFQuVgrhgafx81vfpDlqPMGnrogIhxSfq1nanV+YINSM9VNwahaBE?= =?us-ascii?Q?r7zbY8Xmj62cg2gkF25Elb0Mx475puxHQIdmEc4LRyCN4zkGPcaQZNPrHpiJ?= =?us-ascii?Q?rzOa+vFkHeWS4UXT19EcT+eImo80wvh8sx1N19bh6x6S6HGbyychWEVkaZXB?= =?us-ascii?Q?Fb1IQYlIxNOtwcN9NXpbdBzHw3zuv1rv7z/XCpntgczj8aMjXOyIR8+zvPt1?= =?us-ascii?Q?+gAcaBrffTEocdPT7wWGlPfWPdTu2z9p7EyOYO4mPuauCoA8lrsHImGrZUXW?= =?us-ascii?Q?3hTWgLqV1rLfmQ14x8FmuzinD5rVYNO/+AgX2RLNs60xd2JIEOoz6mb4SUzL?= =?us-ascii?Q?4mcPYdS1o9GIUWwv/R3NoF0GXVwF/KUVR8qqB8pUtEgWowExtHZh6osc7N7G?= =?us-ascii?Q?FD/oiV3kElwhnBkPLduQK6bSSeox1heYEqcw/yDwPbU7cQauVO1QddSXPJyn?= =?us-ascii?Q?0kTwO6PLDt7E+kE7lLZXGtUs172nhLoGr/QrBCY8FKGKpemp03x0dObOaJLa?= =?us-ascii?Q?8gQvD5PaHwUioNSWYbJ6tnZHfEJSkXmlIvqmSX4teqLiIgNDqp+MXFun3cy8?= =?us-ascii?Q?OkAqFYzsfXTN0jAyZyT8P1j4E8SGd5OVgjZS3YewGJC6t/4uI5+O18SL/FT4?= =?us-ascii?Q?FWx4t7MDegf4EtKWeF9rqyaOHSMPlhjOLFmb9PnBP2olFdgGKIg1zCRgJdmb?= =?us-ascii?Q?bJDrXWJakNoK8CxwMizWYu8nY+vgRLPNtGkzh+qqXG1QwIDayDhbt/ExG1qI?= =?us-ascii?Q?31+i0BlZrG875EyqTwSoYSM+LuZvbb9GfH6Mt1QGlBsPaOGfOP6PDpsGAL6j?= =?us-ascii?Q?NZNq3gUt+6SJMB1RwH1IVPpicH2adqmC7s8MiLTIfO7ADdKdxY/XS8AdDNwc?= =?us-ascii?Q?IpFg7pOfLbb7aDsBXJ2HTdVhSVezCgYggaevT/YQwjSSZF70/Oi/16UhF0gS?= =?us-ascii?Q?gxg/CZ+BGxpXN4PJl9f3YdUamFx57gJ6V0rzBJZsAs0ofJIeWTz8a4TuocXU?= =?us-ascii?Q?Kznj5bPbsMRZldykR2+gyexipXUaFePJOnk0pUaz?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9cb7f762-4b2a-4184-13df-08dce5e421e9 X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Oct 2024 08:51:56.4829 (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: olsYnyhCYXB+v/W/xDaF6j8RbXZniIjH94AHV1eyNIqDHGdePu83k9KaQdztZYDb/MEwXZj87NeRQ8kntNjH+A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB8069 On Tue, Oct 01, 2024 at 06:47:59PM +0200, Aleksandr Nogikh wrote: > Hi Ido, > > On Tue, 1 Oct 2024 16:38:39 +0300, Ido Schimmel wrote: > > > > On Tue, Oct 01, 2024 at 02:11:27PM +0200, Greg KH wrote: > > > On Tue, Oct 01, 2024 at 02:20:35PM +0300, Ido Schimmel wrote: > > > > I read the stable rules and I am not providing an "upstream commit ID" > > > > since the code in upstream has been reworked, making this fix > > > > irrelevant. The only affected stable kernel is 6.1.y. > > > > > > You need to document the heck out of why this is only relevant for this > > > one specific kernel branch IN the changelog text, so that we understand > > > what is going on, AND you need to get acks from the relevant maintainers > > > of this area of the kernel to accept something that is not in Linus's > > > tree. > > > > > > But first of, why? Why not just take the upstrema commits instead? > > > > There were a lot of changes as part of the 6.3 cycle to completely > > rework the semantics of the devlink instance reference count. As part of > > these changes, commit d77278196441 ("devlink: bump the instance index > > directly when iterating") inadvertently fixed the bug mentioned in this > > patch. This commit cannot be applied to 6.1.y as-is because a prior > > commit (also in 6.3) moved the code to a different file (leftover.c -> > > core.c). There might be more dependencies that I'm currently unaware of. > > > > The alternative, proposed in this patch, is to provide a minimal and > > contained fix for the bug introduced in upstream commit c2368b19807a > > ("net: devlink: introduce "unregistering" mark and use it during > > devlinks iteration") as part of the 6.0 cycle. > > > > The above explains why the patch is only relevant to 6.1.y. > > Thanks for bringing up this topic! > > For what it's worth, syzbot would also greatly benefit from your fix: > https://github.com/google/syzkaller/issues/5328 > > I've built a kernel locally with your changes, run syzkaller against it, > and I can confirm that the kernel no longer crashes due to devlink. Good to know :) I hope this patch can be accepted as-is instead of a much larger patch. Will copy you on the next version. Thanks for testing!