From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8873D606A330 for ; Tue, 27 Oct 2026 07:35:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=ShPz/LB/ Received: by kanga.kvack.org (Postfix) id A3C256B05F1; Tue, 27 Oct 2026 03:35:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A145E6B05F3; Tue, 27 Oct 2026 03:35:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 929D76B05F4; Tue, 27 Oct 2026 03:35:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 6FB476B05F1 for ; Tue, 27 Oct 2026 03:35:55 -0400 (EDT) Received: from smtpin27.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 017C3C0927 for ; Tue, 27 Oct 2026 07:35:54 +0000 (UTC) X-FDA: 85367597070.27.4D5670B Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf17.hostedemail.com (Postfix) with ESMTP id 0816540003 for ; Tue, 27 Oct 2026 07:35:52 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b="ShPz/LB/"; spf=pass (imf17.hostedemail.com: domain of dev.jain@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=dev.jain@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793086553; b=os1pz6Do9vhGu6F97jcXJx4EqPJ3ExM1vUxQxwCLTRTUfC3x775Xt/0yCmn/Ut2MvlsVOi JU4n+ILnZoV+OXW+7O6/Z32XAJ3vOxaAQS+c4GowqWGkViMRoU4ETcJ8LGtkk5RUyCx38Z dfzLGzGy1xK/no8Ojqn05SmINNKv88c= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b="ShPz/LB/"; spf=pass (imf17.hostedemail.com: domain of dev.jain@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=dev.jain@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793086553; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=5jc2ZtnsslhTBje2qQpVD7MrTZfTUlL74O4i/llDB/M=; b=CHZFbe1WSbpt+HpYNmngjq/bVT76qyx/zyAhTN6eo4M1nhvmTTKTt6uTM8oxrhu9gP3jeq 2SUxl3kfnNO8y5Chqkt65E8ElpxdWfFusCh02gXsoxSdxToPLMxSI+dLll9xzHrWmio2ZJ rz7l/SXmqayBcTR1dycLWu3U0TImGRE= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BB8F81477; Tue, 27 Oct 2026 00:35:48 -0700 (PDT) Received: from [10.163.152.160] (unknown [10.163.152.160]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 316693F673; Tue, 27 Oct 2026 00:35:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1793086551; bh=n2WrtA8FsjLacOwP70K0qkcnkliELHh0b55ywQMgrm4=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=ShPz/LB/JTXMSaXWoN89wpg1R0MFhTQ3+OYAWgQenVr07qFiwcr+BtH2v6xKKQfRM QrYTx4Q3mPU1qcZAPdg41yN63hG8hPH4qkEAk45cxkJ8LLmOSK716gyfQv1IvIJqjZ R/89T7N51QEEo+TuFrpiXNQLA0t0iBWtwxXvK0jA= Message-ID: <21091d4e-0afb-4b5b-84ac-b36bac58e40f@arm.com> Date: Tue, 27 Oct 2026 13:05:27 +0530 X-Archived-By: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 26/46] mm/mmu_gather: fix flushing ranges with 4 GiB or larger To: "David Hildenbrand (Arm)" , Andrew Morton , Johannes Weiner , Michal Hocko , Qi Zheng , Shakeel Butt , Lorenzo Stoakes , Kairui Song , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Baoquan He , Baolin Wang , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kees Cook , Peter Zijlstra , Jann Horn , Pedro Falcato , Hugh Dickins , Pasha Tatashin , Pratyush Yadav , "Matthew Wilcox (Oracle)" , Jan Kara , Zi Yan , Lance Yang , Rik van Riel , Harry Yoo , Alistair Popple , Nico Pache , Ryan Roberts , Usama Arif , Kiryl Shutsemau , Matthew Brost , John Hubbard , Peter Xu , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Oscar Salvador , Minchan Kim , Muchun Song , Xu Xin , Chengming Zhou , Chris Li , Kemeng Shi , Nhat Pham , Youngjun Park , Gregory Price , Joshua Hahn , Rakie Kim , Ying Huang , Jason Gunthorpe Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-cxl@vger.kernel.org, Josef Bacik , stable@vger.kernel.org References: <20261027-fixes_core-v1-0-6f74bec9a5bb@kernel.org> <20261027-fixes_core-v1-26-6f74bec9a5bb@kernel.org> Content-Language: en-US From: Dev Jain In-Reply-To: <20261027-fixes_core-v1-26-6f74bec9a5bb@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: 0816540003 X-Stat-Signature: e3c8qnus9hp7dbzhzq7gf6o1aeyetju1 X-Rspamd-Server: rspam01 X-Spam-Status: No, score=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=4.0.1 X-HE-Tag: 1793086552-743909 X-HE-Meta: U2FsdGVkX1+wgrNmJgG3x6ZBN/xSK6JUlezju9ZalC7jCqkpex1klGmuXAbp6Hpiad1r401dTy/uHUrCmRITeEhaloTMvzUAIS6niqVRX5urPDN3KiunIQ7ugUNA/bN3EILhWluoclRLN/DLzTYBSJPk1sU/6SWwlToRuX5qLqn46ijegDvoS8vsMJ1KkW3Dc3ZZwQgK02xyLG4ATfk7ms75t2+3WSXLFXiy1RyTxTd++6WYr+rRWG7Z6qqp0YOVVZ1/5V02yt977hNQh0zHX0/p2lZz28AI50VCaVmfscHwIHdNuS9ZUdvswAIi0Dp1cWL5hXjhYJV0/Tv/d9Cti4sb6V/rgsGM+8Al8paWkiSyyRt7itaQDrV5T4uD9zZXCo4JCNWXPPgGbBjLPwcjBTaTUmBIxyOzCEQLjBbG9e5UnBvqCVz4s0CRKZp+zNTWvrGPHiVtF+Vf0HnQrIh53RI+8g2BL4ZoIYdhMuU5VJ3D4ZzimcTZRrTS2E3lmYlW+/PGZgCCWo45Fex7d3a/ICHl+4ssHc975P7+qFWIobvt6WAgdJ4R+Y3zlzQLj/HklFHS7tRzNuSho6ZOo6m/bmEm9Pay7FdKjd7EOluBVgcY7QkK8Hxl2d6RktL/CeFuPF5FlT7RA18BxqxC7rLdIgFp1EtbA+bGnK3bZ5V+qzXkoDWoaYGErI/sUc2jGlE0Hh2oOiuLoM0anXT1PtoXjiA1UB64sMaNTcH79MdTcQ/Aqu1Ot8j2JRAAuvhiv4ZiYDoLh2xMycuZPwIS/jg2DBxsIKYzlbV2k05vIuFCB0jtUd2mI4+BsCVwpCCaMT1yUFP4LWi6k9rtv15uQlRXSlvTjfthzsSj7gCvZQkFDCkeUZbOWjhjDIYveI9Vu8AbIC3FURudoso1nkjYCM0nyhUDEOdbZB6W9SAIXZbjHC7kvg+Cwj38OhFG/sMZFZ4H4d4j+nrp0qQFI9C/UAE GGCB+MV8 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 27/10/26 4:47 am, David Hildenbrand (Arm) wrote: > From: Josef Bacik > > __tlb_adjust_range() takes the size of the range which has to be flushed > as an unsigned int. Its callers, tlb_flush_{pte,pmd,pud,p4d}_range(), get > and pass an unsigned long. Consequently, a range that is 4 GiB or larger > gets truncated, possibly to 0. > > On arm64 with hugetlb, a 64k kernel can flush 16 GiB hugetlb PMDs, and a Nit: this wasn't obvious to me. Better expressed as: "a 64K kernel can have 16 GiB hugepage mapped contiguously at the PMD level" > 16k kernel can flush 64 GiB PUDs through tlb_unshare_pmd_ptdesc(). So > at least these two scenarios are affected. > > Fix it by flushing the proper range instead of the truncated one. Nit: after reading this I thought you are passing some other parameter now. But that is just a type change. > > Fix generated by an LLM and sent by Josef Bacik in private. > > Fixes: b528e4b6405b ("mm/hugetlb: add tlb_remove_hugetlb_entry for handling hugetlb pages") > Fixes: 8ce720d5bd91 ("mm/hugetlb: fix excessive IPI broadcasts when unsharing PMD tables using mmu_gather") > Cc: stable@vger.kernel.org > Signed-off-by: Josef Bacik > Acked-by: Lorenzo Stoakes (ARM) > [ david: use two-tab indent, simplify description ] > Signed-off-by: David Hildenbrand (Arm) > --- Reviewed-by: Dev Jain > include/asm-generic/tlb.h | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h > index fbe1114e9a443..3f4a180b48f3c 100644 > --- a/include/asm-generic/tlb.h > +++ b/include/asm-generic/tlb.h > @@ -350,8 +350,7 @@ struct mmu_gather { > void tlb_flush_mmu(struct mmu_gather *tlb); > > static inline void __tlb_adjust_range(struct mmu_gather *tlb, > - unsigned long address, > - unsigned int range_size) > + unsigned long address, unsigned long range_size) > { > tlb->start = min(tlb->start, address); > tlb->end = max(tlb->end, address + range_size); >