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From: Lance Yang In-Reply-To: <20260622142102.pcmr5pftshj5lvju@master> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Stat-Signature: sg745b8a5guwizznx6dxycufbzaeycab X-Rspam-User: X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 5B44C1C0010 X-HE-Tag: 1782140419-97409 X-HE-Meta: U2FsdGVkX19npzfcAi8glV8nGLzOoe67KvEmH2H/USpw3grJB+nZpTDeQmsaPlVvWpeExcW3iJWdiEKlZossuh9groK+D+c7lMBhyXDoVI6exBUfgAUkb5fCVrVoxL1DtoHVtzpi8KxKyIbQLO24hyqMuPJ1rEVHja9NWaVtMGkSPDpPU7jEk3sqrC1P8TH3m28xnw+LhQdogW8nZa62nIo0o3hzdHwLfMsNG46pJYD9KPhkH52+bzvwkG2BvoU17/oB5EDo9rqKkudwPUO5jrc8ZCmTfLO8S+Rx3JJT52nVOwKWkBQHfKuFfcyaewGLZcDIyLWRVcWXhtrBk9mSYnokyklEtpnrsO9jnPkR5Obx4vI3sgJW66JcKw85AcYeIohmeFxkJfWeqr18SY1zHoIUQo6N4OsDcYdphD2bMsA69ys3xjTyZzNmjr56Mzvap4XH4GCXipC0MOxraNnL4JNfHnsOBhq3PQU9aDAvXl8R9vAK8ZcGK0IC/+2QQtwdy3U+x2kn9iQlePt/1E1yJAKHKPRJuiO/0asa7K/jBMA6/QEcYDdxOJkcNyIXeD3t2ErAz2zSiw3YV+aqHkHn5+IQC312brnuMmDHhp73EqSy0dPCW2u2BYs9YDO9o1YIQV0aRXNnwZsqtKN7QG6NBBAkUoCjqJSsZkuA8rTVtiL7954LkPBaqq8uTk/vuSVs6E8Hj8eH5RBw4t1ZS8nwMx1kzc81vddxpvg7/jDgU3vvk1GZ3uYzkA6tOo0V/LDS/s8IJz7/Ur0RpHA93WIDoyCsU9ql0+mNbMmLyjl/HB2UYW3hxnzE4KTz+cr8jW9FGAEP08hC85ButOXVvETzqv05iUrrPXfz373jlhll7+WQxLOS8ROHIv1TuDw3RX31/r45lMA/xvicB8H2//2m3RY4X60D4JGFISQXw2UV801OpXb9UwEgXFH5tahDdthVYEm2vnfRJEpkDq2We2Y iO7kkNP+ QFMc/QxKBBXLJ1KAMyEnFZFoSizB9+RtoR2qdJibZaLuV52UpXdXpj3deY8vOKfwrPiF9rnoZTtmMuN3ZE0gdss7HSH6WREvbmo4BhH1xuDbzoiSy2P995dhmDnjz6jpemZ3L7ZNbeNHgzshaaYHEao7/lwkWzqYX5NbFG2E/V3bT/IXRNx08oid3zuM+XAZ8ZK5KvXJkw43MeyNpYhqHahUBqzkUJ59dHuuSrZTImULj5Ny0zRn0MMdKbXZKZCM3DODjCZdiXXUFWGcGbizLtlPFIoz1tb7p9fu+C563140ZVw57M+eMvTgeGPVhaAMASYRtD+HGbV9zvrtgajimYaGdC9w0NU4BX57vYEMYl7HiKlADtZVXyigXCRXUBeOf6p/V Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2026/6/22 22:21, Wei Yang wrote: > On Mon, Jun 22, 2026 at 02:46:40PM +0100, Lorenzo Stoakes wrote: >> +cc Lance, linux-kernel >> >> Your subject line is 83 characters long and is way too detailed how about 'fix >> device-private PMD handling'? >> > > Got it. > >> You forgot to include linux-kernel@vger.kernel.org on the mail, lore seems to be >> a bit broken atm but in general it's helpful to include that. > > Got it. > > So usually we send a patch to both linux-mm and linux-kernel? If so, I > remember is later actions. Yeah, please keep linux-kernel copied too. For MM patches, linux-mm + linux-kernel is the right default, IMHO :) >> >> Also is useful to make this [PATCH mm-hotfixes] to make it really clear it's >> intended as a hotfix. >> > > Got it. > [...] >> ----8<---- >> >From e6a3c1c782714ed831c4d46a14bb99226423bf59 Mon Sep 17 00:00:00 2001 >> From: Wei Yang >> Date: Mon, 22 Jun 2026 13:06:51 +0000 >> Subject: [PATCH] refactored >> >> Signed-off-by: Lorenzo Stoakes >> --- >> mm/page_vma_mapped.c | 20 +++++++++++++++----- >> 1 file changed, 15 insertions(+), 5 deletions(-) >> >> diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c >> index 2ccbabfb2cc1..17dff8aab9f9 100644 >> --- a/mm/page_vma_mapped.c >> +++ b/mm/page_vma_mapped.c >> @@ -269,14 +269,24 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) >> /* THP pmd was split under us: handle on pte level */ >> spin_unlock(pvmw->ptl); >> pvmw->ptl = NULL; >> - } else if (!pmd_present(pmde)) { >> - const softleaf_t entry = softleaf_from_pmd(pmde); >> + } else if (pmd_is_device_private_entry(pmde)) { >> + softleaf_t entry; >> + >> + pvmw->ptl = pmd_lock(mm, pvmw->pmd); >> + pmde = *pvmw->pmd; >> + entry = softleaf_from_pmd(pmde); >> >> - if (softleaf_is_device_private(entry)) { >> - pvmw->ptl = pmd_lock(mm, pvmw->pmd); >> + if (likely(softleaf_is_device_private(entry))) { >> + if (pvmw->flags & PVMW_MIGRATION) >> + return not_found(pvmw); >> + if (!check_pmd(softleaf_to_pfn(entry), pvmw)) >> + return not_found(pvmw); >> return true; >> } >> - >> + /* device-private pmd was split under us: handle on pte level */ >> + spin_unlock(pvmw->ptl); >> + pvmw->ptl = NULL; >> + } else if (!pmd_present(pmde)) { >> if ((pvmw->flags & PVMW_SYNC) && >> thp_vma_suitable_order(vma, pvmw->address, >> PMD_ORDER) && >> -- >> 2.54.0 > > If we prefer this way, I will check and take it. And +1 on Lorenzo's diff. Much cleaner. Cheers, Lance