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charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BN9PR11MB5276.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8f2f5f14-d421-4e2c-776b-08da4dd26ed2 X-MS-Exchange-CrossTenant-originalarrivaltime: 14 Jun 2022 06:52:22.3948 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: ocARgZkFSpxDO2veeTIWXKhKIbqRbDsRJEKmFK59zu8aDwmbKL3emWKAaJ/DPRpycir/22+5+BCrKXCOfmZ7BA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR11MB2808 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > From: Lu Baolu > Sent: Tuesday, June 14, 2022 10:52 AM >=20 > The iommu->lock is used to protect the per-IOMMU domain ID resource. > Moving the lock into the ID alloc/free helpers makes the code more > compact. At the same time, the device_domain_lock is irrelevant to > the domain ID resource, remove its assertion as well. >=20 > On the other hand, the iommu->lock is never used in interrupt context, > there's no need to use the irqsave variant of the spinlock calls. I still prefer to separating reduction of lock ranges from changing irqsave= . Locking is tricky. From bisect p.o.v. it will be a lot easier if we just ch= ange one logic in one patch.