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Fri, 10 Jan 2025 15:08:39 +0000 Date: Fri, 10 Jan 2025 09:08:34 -0600 From: Ira Weiny To: David Reaver , Song Liu , Yu Kuai CC: David Reaver , , , Krister Johansen , Ira Weiny , Thomas Gleixner Subject: Re: [PATCH] md: Replace deprecated kmap_atomic() with kmap_local_page() Message-ID: <678137f2106fd_167faf29436@iweiny-mobl.notmuch> References: <20250108192131.46843-1-me@davidreaver.com> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20250108192131.46843-1-me@davidreaver.com> X-ClientProxiedBy: MW4PR04CA0203.namprd04.prod.outlook.com (2603:10b6:303:86::28) To SA1PR11MB6733.namprd11.prod.outlook.com (2603:10b6:806:25c::17) Precedence: bulk X-Mailing-List: linux-raid@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SA1PR11MB6733:EE_|SA2PR11MB4825:EE_ X-MS-Office365-Filtering-Correlation-Id: fca427cf-a041-4bbd-7d62-08dd3188a9d2 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|1800799024|366016|7053199007; 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It appears to me that none of the call sites in this patch > depend on disabling page faults or preemption; they are all mapping a page > to simply extract some information from it or print some debug info. > > [1] https://lwn.net/Articles/836144/ > [2] https://docs.kernel.org/mm/highmem.html#temporary-virtual-mappings > > Signed-off-by: David Reaver > --- > [snip] > @@ -1387,9 +1387,9 @@ static int md_bitmap_init_from_disk(struct bitmap *bitmap, sector_t start) > * If the bitmap is out of date, dirty the whole page > * and write it out > */ > - paddr = kmap_atomic(page); > + paddr = kmap_local_page(page); > memset(paddr + offset, 0xff, PAGE_SIZE - offset); > - kunmap_atomic(paddr); > + kunmap_local(paddr); For these we defined memset_page() With that change: Reviewed-by: Ira Weiny [snip]