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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?9YiVxquaHgKYzUPqQSbvN6bKnLkssCtroqjgbTrFJfjqEp9jAMt6VxLtXOOG?= =?us-ascii?Q?ciW1HCeOApt+YRG4FJpDYG0e9cIBDGGA+sYNoHFRSa62KAPHcFzIue28uwTL?= =?us-ascii?Q?QYREqWnBztZyRxKVKlUWJS9sqCvD3UvcAIC1Sfi2RS4fcII9zCr2CjJKbxUX?= =?us-ascii?Q?XN/RiYkfDsRTUbZn7hXLAR3FlE+Or4DPQSaxp/iZQ5GpvyCkG6rBwSsLUfuG?= =?us-ascii?Q?Jt1M8epNPnTy/c0e14n7En+sX9L8SX8P9UYaQ+JMev++wnrpn4a4f7yXsqk2?= =?us-ascii?Q?31HEd7GmI9LvebCC2KulPJz6IhKplU8nTVTb+gFij4U0fAVr7a59x3a14ItU?= =?us-ascii?Q?YPozu3JLdGkdy/tsfQG2Og0m+GyPSRs30xEFYd+/sZePW0UYNITc7d6eYzIn?= =?us-ascii?Q?ZlIzpWbAUORhaVvhvssfwl6CHfsx70Azyb2WAVyoLQPQjcrb9D2u54iNbGUn?= =?us-ascii?Q?+8t7lxbPM6/p7Dl9Kx/XfIjabMonDP4K8+IYf8beXQFESJclR7tCXZrNAhau?= =?us-ascii?Q?nDuFRegIIikGxuSkbYJKbrPsuR8G0j49Oi98wy1rPE/XH5QNUcRlcV52W4x8?= =?us-ascii?Q?IfdGVacAiRPEjRdxY33RgD7LjLmpoDyNwHow4xj+vh3+Kd+Gh1L4CZwjtLiM?= =?us-ascii?Q?hdKXPZs3w5OHE+cI9ooAINzGpzP1greZhsEQJMVKd8+2+R0uu2BWZZnMmPZe?= =?us-ascii?Q?cFQjGVjUEaSN3gWUrg6MDy+v3e3BN1zdQuJUdnv7ro8KF5fm4v4P4hjIPemf?= =?us-ascii?Q?8W7zt5lIiK2YCItXzfP7usAzUPq5Dn1bbQBySgSLJKEAIJkuA0ATLTt8KKfF?= =?us-ascii?Q?QZqorRpBuKIogLARNSVg8IiEOjEWwd5kdacTslnlYiFE3EoXkE0PTQWIDPIS?= =?us-ascii?Q?WNY1OYIOInzFwFdWKlNRO/eWN2n5gSSRO/bKT8PVBlZ9sKYzgT/fEsyDdT7i?= =?us-ascii?Q?s5fM/6DScNj6SvK1UYmGvt1Him594FA3atWVixxl0UXwEoe8KNgfpi8HtYV+?= =?us-ascii?Q?raZbcklbd/Sz5VaBRzfcKedjIwByzW3PBoRBkRPIAuNlycMdMArQhWVbPEVQ?= =?us-ascii?Q?7imAiDVgwstUsdZ2aIwzodkNDFn7B8l1XMfpbV6uwuCf2kGoCeOJ8lMH1Trd?= =?us-ascii?Q?cClDct5cZaMi19z1PBaDzUfjF2rJJBidtZGpq22xOZs/rQXn47XmOLTWsI40?= =?us-ascii?Q?uLZS8Mk3wYweK66/nPb3y0PuOUnYpVkDXcZsX6Sl1lCxnO/MRdlMAlZDeOgB?= =?us-ascii?Q?wNRhjNAClUdUlxKPKkci9E5GOMivOawpx2Mw32vcU/M0fP65DxPqDJ4zkiIC?= =?us-ascii?Q?ZFv9n6gl1MWaCpA9UQbXFO64sY5V63dTy2yev3Vl7o0DLMG/FcAKSB5jzp9q?= =?us-ascii?Q?uMXTocx+rY8+6P6PsSRmm46xLgDBt8P6eZF1dP93tPhrLmZG7IRIe0JB814f?= =?us-ascii?Q?XCUQdojrFM+QO/Ux01uOdjXCSayChmLrDpLJvuOcJn0FNjA8Yfhf+SJfwno0?= =?us-ascii?Q?dLmX/1Qw/aKJMq4MAeVR5Xl9z+NSgHuayctcGC65W76jKkxW4oL1dsp6m3rC?= =?us-ascii?Q?LkzXAP/JJINhQWyRQxGGVuvYgczWrjNlpLhqPV7j7QmF6sZquXWvMU5qqR1n?= =?us-ascii?Q?Jw=3D=3D?= X-OriginatorOrg: prevas.dk X-MS-Exchange-CrossTenant-Network-Message-Id: d52972bc-dfe3-4d5d-7fb5-08de39802776 X-MS-Exchange-CrossTenant-AuthSource: AS5PR10MB8243.EURPRD10.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Dec 2025 13:12:51.4889 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: d350cf71-778d-4780-88f5-071a4cb1ed61 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Ia4XoxAkKeaPfw1XlaJ8Jcbuzjk0A7VVRD+Sgjxo6wtVlp/GF2WdK9NGrdQP4NlsDo5DxKb2aq+nXvLz7ePzeT9QfTWnxi4ggF72zom6chk= X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR10MB7900 On Thu, Dec 11 2025, Peter Rosin wrote: > 2025-12-10 at 23:54, Peter Rosin wrote: >> Before commit 3092bde731ca ("iio: inkern: move to the cleanup.h >> magic") I think this could have been solved with a number of: >> >> - mutex_lock(&iio_dev_opaque->info_exist_lock); >> + mutex_lock_nested(&iio_dev_opaque->info_exist_lock); > > Oops, we need something clever for the (missing) subclass > argument to the mutex_lock_nested() calls, which I simply forgot > all about. It should have been: > > + mutex_lock_nested(&iio_dev_opaque->info_exist_lock, *subclass*); > > I don't know what sane subclasses there are. One thing could be > the recursion depth, but I don't think we want to keep track of that > just for lockdep? Another is to use one lockdep class for every > info_exist_lock, but that can generate a lot of lockdep classes... It doesn't seem to me that that info_exist_lock is the proper mechanism for whatever it is it is protecting against. I'm not even sure it's needed, because if the device could be unregistered while somebody has a reference to it, why is it even allowed to take that lock in the first place (i.e., why is the memory containing the info_exist_lock guaranteed to still be valid)? But, since I'm not going to propose just ripping it out, perhaps a better approach would be something like what the gpio subsystem did in d83cee3d2bb1 ("gpio: protect the pointer to gpio_chip in gpio_device with SRCU"), at least superficially it seems to be about a similar problem. Rasmus