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 745D5606A31D for ; Fri, 30 Oct 2026 23:57:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=H92dZjxo Received: by kanga.kvack.org (Postfix) id 590826B05B1; Fri, 30 Oct 2026 19:57:54 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 518D26B05B2; Fri, 30 Oct 2026 19:57:54 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3E0B16B05B3; Fri, 30 Oct 2026 19:57:54 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 117FF6B05B1 for ; Fri, 30 Oct 2026 19:57:54 -0400 (EDT) Received: from smtpin29.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 8BA5114042C for ; Fri, 30 Oct 2026 23:57:53 +0000 (UTC) X-FDA: 85380958026.29.5391289 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf10.hostedemail.com (Postfix) with ESMTP id DA057C0006 for ; Fri, 30 Oct 2026 23:57:51 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=H92dZjxo; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of sj@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=sj@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793404672; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=yYH3ZHoy3wMBa62rdRKFlOT5iUEACgCaryz4Ge7v3YA=; b=NO/OPLvcaGAxGPPUQBPoBRuoI353ija+iq02VZqSA0kRkcpk096ZWqzRZT8flyos2eNmx6 qIj/JHxkZFdHTe9NgHYJ+Sm9DjFZTiRrkB5kvE5cAvZaAJKktW4/a8uSPaSxs/jxHRWytV 323YACUwgaObxVKUspGQNMM6Gyc4/i8= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=H92dZjxo; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of sj@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=sj@kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793404672; b=gFBa4w1Q+aKUQ/uPPN0PqFZXFUH9ziKV+2j0Een7X5+teap7fr1fa5NA35GsLRkG79Ljgy +UT+xkamWRXCfP4GfkRPtmNUv17kCAMvUnBOYluoPyRBn+hkomv/xMlib1l6/naS0AqhSZ dCc9u8Zgn4CJWUn4KcXuUOkKy8hBlaU= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 1F46E43CF9; Fri, 30 Oct 2026 23:57:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC0D51F000C1; Fri, 30 Oct 2026 23:57:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793404671; bh=yYH3ZHoy3wMBa62rdRKFlOT5iUEACgCaryz4Ge7v3YA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=H92dZjxoEBjeg93MdfYqW/6IAuzONdaBmZ/OVUIsM/rdieejBoUuPSaLoOlo/X9o1 LlUIR8KOWVCHXQJ0RXY6QJvgcTFZDjQ/SKuYB5lMYKKlKkip+akHrFT7sXCC+QTS8t cXMzHeO+7K/QXNLgWd24gdJG0IuXHSKRDFzXJJyx+460C2uW4fEZiprWvkS9p5Z/xm XcsKKOfRK6ab+J2juDoX2gfEAAT5ljzSTYck93sZyWI7z36GkDg4BEq9Fni2WcB9aI mjhqPrj/7BdZ6vAmuIqFRM5iI7AFLcUsJ30+CpY1jeLBqohnWPf9I1ONGO9xBX9uKC DGSaHM1C+gE2w== From: SJ Park To: "David Hildenbrand (Arm)" Cc: SJ Park , 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 , Dev Jain , 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 , 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 Subject: Re: [PATCH v2 27/47] mm/mmu_gather: fix flushing ranges with 4 GiB or larger Date: Fri, 30 Oct 2026 16:57:41 -0700 Message-ID: <20261030235742.87036-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <6ac05dd8-321a-4c2e-bce8-bd7ffcac9eac@kernel.org> References: X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: DA057C0006 X-Stat-Signature: hsa6hd153tgkq17f4ny636r98i8teigm X-Rspamd-Server: rspam04 X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1793404671-670749 X-HE-Meta: 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 xJkfggYq oRQ1PGoPPpr3yhoGygLhdSi2tOloviZQtFYDCt/TlkKfApwReTU3lRLUGMe0LpVq5PEtVKz7tBYrmMQnGwciCgOSzlf25v8XRnQAL9pjgIBL5RmvBMf0+IIX4h8Vx+95mdVckgGyem23BrQTdmFJ/wbe5NfPQzzA8AqHftEmEtoaR+lvQviHVbnAAqU7rfbXXOIqbdGZ3rWHarprqrN/x1FMxwxZhVL7W6Q0hpbOTXgHiW11Ol1KPnykU8CIF2c4vpZXenGOix7yL4DZ2xnlxhnriCnBV3VjBsBKyMqGYE+owUKw914Hx0dxWPKCq8GvgRCjdVbhOHDGxigXozr/XbZcpq5u75EmI4YvdEkdVrUTa3d/pExFtdjDT9HI3GYDTV7fHwmPFAqlsMbxWl4LMMMrOND0v3zPDjStV 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 Fri, 30 Oct 2026 12:19:46 +0100 "David Hildenbrand (Arm)" wrote: > On 10/30/26 12:15, David Hildenbrand (Arm) wrote: > > On 10/30/26 01:57, SJ Park wrote: > >> On Thu, 29 Oct 2026 21:33:22 +0100 "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 have 16 GiB hugetlb folios > >>> mapped contiguously at the PMD level and flush them when unmapping, and a > >>> 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 by > >>> properly using "unsigned long" for range_size. > >> > >> Makes sense to me. > >> > >>> > >>> 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 ] > >> > >> It seems the convention [1] is to put the above modification note right before > >> the last S-o-b: of David. Maybe you forgot moving it after adding R-b: and > >> T-b: from great reviewers? > > > > It's "b4 trailers" that apparently messes this up. I don't think it really > > matters (some move it above all trailers), but I'll fix this up when applying. > > Thinking again, I *think* this order is correct. > > People reviewed and tested with these changes. > > it would be something different if I modify a patch while applying it. Because > then, what people reviewed and tested would be different to the original version. Makes sense to me. Thank you for the kind clarification! Thanks, SJ [...]