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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Matthew Brost References: <20260529172331.356655-1-kas@kernel.org> <20260529172331.356655-5-kas@kernel.org> Content-Language: en-US From: Balbir Singh In-Reply-To: <20260529172331.356655-5-kas@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: ME3P282CA0073.AUSP282.PROD.OUTLOOK.COM (2603:10c6:220:f6::6) To PH8PR12MB7277.namprd12.prod.outlook.com (2603:10b6:510:223::13) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH8PR12MB7277:EE_|DS0PR12MB8319:EE_ X-MS-Office365-Filtering-Correlation-Id: b6fa8bca-cbdc-43c6-b9fb-08debf732edf X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|1800799024|366016|18002099003|22082099003|56012099006|4143699003|11063799006; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PH8PR12MB7277.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(7416014)(376014)(1800799024)(366016)(18002099003)(22082099003)(56012099006)(4143699003)(11063799006);DIR:OUT;SFP:1101; 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The PTE-level change_softleaf_pte() does this correctly; > mirror that here, matching what copy_huge_pmd() does for the fork > path. Without the carry, a plain mprotect() over a UFFD_WP-marked > device-private THP strips the bit and the trap is bypassed on > swap-in. > > Fixes: 368076f52ebe ("mm/huge_memory: add device-private THP support to PMD operations") > Cc: stable@vger.kernel.org > Reported-by: Sashiko AI review > Signed-off-by: Kiryl Shutsemau > --- > mm/huge_memory.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 42b86e8ab7c0..b7c895b1d366 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -2663,6 +2663,8 @@ static void change_non_present_huge_pmd(struct mm_struct *mm, > } else if (softleaf_is_device_private_write(entry)) { > entry = make_readable_device_private_entry(swp_offset(entry)); > newpmd = swp_entry_to_pmd(entry); > + if (pmd_swp_uffd_wp(*pmd)) > + newpmd = pmd_swp_mkuffd_wp(newpmd); > } else { > newpmd = *pmd; > } Reviewed-by: Balbir Singh Balbir