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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?D6W+DJxjxMKNIa+dqvg3bgjVqutsId9wyRH9RZopccl9InwKyZzktiXiyAkE?= =?us-ascii?Q?eVr3JOzZGrluzvWg8PxqwNKmXQdGBr+nfkchvQ+qKzsYJg8lkZ5GayvAl0B+?= =?us-ascii?Q?G1XoUrrqv/RG5B1/bnoZI4QZbKv1w96dA24Hk6IZx5eyATkqI+HLheBHwyJV?= =?us-ascii?Q?to6qaNV6vR5AjaHbhGqL7v4hLP98Z/jzZX6EP2d3O+oOTpShh0pumhtRAPL4?= =?us-ascii?Q?+UU0CghHabMEl3YSYFO3gLAEQgFG5NvLmomoTi6C5QXhM8rivleTj+xox/d4?= =?us-ascii?Q?P0f7eZp79DeFd7+54PG8viudaoWJSeI3arKfEgmdB/SKiF1eB7XXIrz347Pp?= =?us-ascii?Q?HO/4dzP/yJL22cRtCauaO8RiJFzNP/fWxYoUEt1yh38fos9p8wX9IuKMXba/?= =?us-ascii?Q?1tntCSBfrAIXDfpHYtf0XtVWQTYHmWOL2zWHC1EQzkrtCCILAadV/s37K749?= =?us-ascii?Q?BTKqUcbz7EwkCEnZg1dMFG+t4BWHA6GydopnVG7r7Qls8KS0Y07jxfC7Cxch?= =?us-ascii?Q?TlkZhWspQ4hnMOyY213KVU4Mo7xkiDG201moWhxDC46Sf2rOQ9YruSdJNzgx?= =?us-ascii?Q?WmgCtUhXESqHSmiqjkp4KEOeFPliWH42C3Lw6NZrxDTA+N7lErF5kkMKKJhU?= =?us-ascii?Q?nvE67tdqG1B5wtEhnC1TNLfT8cIVfqdlQrdGHUyFg0yt1+rnpOgm9qs1oX7Q?= =?us-ascii?Q?uztxKBGiaHNtTdug2JvI/JbUouZKsvaAZL2DcGePN/Lu0e0SxlMKxo7O44FF?= =?us-ascii?Q?chsuifnmN7UfffCxQl+sUusM7G8C39Qh5M/MTmpa54qjFaOIORxt8yPv2rc8?= =?us-ascii?Q?qwkbehJ6+/SkxvY8pSY0ibqV1FirWkEsGHqmEGhKbdtUiDfmwGwDIE0yHFGi?= =?us-ascii?Q?hB4OrLex12M2RmUQEC/UmhszUmgj0IHVG4il4zwkDEkRN+B9YHmGJ3Po9qK2?= =?us-ascii?Q?UPe1mgMA28yudw9BO2CWu6jcdROQG3UjdUBDvtvgDKuRcoMMm7xNL7hEO7fp?= =?us-ascii?Q?t8QU9YBp/am9kSgNXRxRecw1pEHZ4zmx5zQG3LZvW0/bB1+n2P3YIDKZgXuP?= =?us-ascii?Q?X6EUguD9U5MimW+xLjBfikWYzRlafw0xu1bKVRJbLiv02OKeiyOsnyCWy7fn?= =?us-ascii?Q?o9AuYQVi7pNqsg7JFF0YZGC7A3U7XMgifkytoOqckGOEwYFU3yqNEopy/1Ds?= =?us-ascii?Q?KvHkfgcFsMS8/u4KFn06D9bUCKFKwzMBZIM5MgOYxOqRRARaOiHN4hB9rzgL?= =?us-ascii?Q?GgHWoDH/cqD34pCwYW2aTrqb4FPlfLNQ0qKnGmaOfibN15RalwdP/XRgK1h+?= =?us-ascii?Q?ZRo+L88uyElqgvtBdMvGOJ8NIjHmtRayI6Bl8Ebiys5/Rw=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d4542ffb-ab55-48b6-198b-08d98787e1c5 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Oct 2021 22:39:52.9563 (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: M1LX9wAJoYmniG/Pe8Ba5yQK9bMwLTUMBHElY28zk4PK14F8bueaeZ27vl2+A5MR X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5239 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Mon, Oct 04, 2021 at 04:25:51PM -0600, Alex Williamson wrote: > On Fri, 1 Oct 2021 20:22:23 -0300 > Jason Gunthorpe wrote: > > > The next patch adds a struct device to the struct vfio_group, and it is > > confusing/bad practice to have two krefs in the same struct. This kref is > > controlling the period when the vfio_group is registered in sysfs, and > > visible in the internal lookup. Switch it to a refcount_t instead. > > > > The refcount_dec_and_mutex_lock() is still required because we need > > atomicity of the list searches and sysfs presence. > > > > Signed-off-by: Jason Gunthorpe > > drivers/vfio/vfio.c | 19 +++++++------------ > > 1 file changed, 7 insertions(+), 12 deletions(-) > > > > diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c > > index bf233943dc992f..dbe7edd88ce35c 100644 > > +++ b/drivers/vfio/vfio.c > > @@ -69,7 +69,7 @@ struct vfio_unbound_dev { > > }; > > > > struct vfio_group { > > - struct kref kref; > > + refcount_t users; > > Follow indenting for existing structs please. The next patch even > mixes following and changing formatting, so I'm not sure what rule is > being used here. Thanks, Sure, I generally err toward nixing the vertical alignment. It generally is a net harm to backporting and I don't care much for the poor readability of 30 chars of whitespace between related words.. I look over the patches again and check Jason