From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0B73B606A31B for ; Tue, 27 Oct 2026 15:43:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=NJeyFFXF; dkim=pass (1024-bit key, unprotected) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=05qekNvl; dkim=pass header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=UkMXw2Gd; dkim=neutral header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=MICKFMxi; dkim=neutral header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=iONvCRX6 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=G4U5OOZBCiWmK00YiJ7rS5NugQwh3GpoktzIg7zSeoQ=; b=NJeyFFXFbn32rUqKrWoZ9mZ584 M5Nfnvz/OMLBmIX/yDPckEMcTzpdY6loe6wYU9cw/fewHuixmWVxfU3Xq8fpadLljekm+2WsdL6Vb 79BvilQH4Tp+SWEa1bR5PgkB4B39jfx2Rb5Rrx2yCTVeNJyCtL1z1oQBgzE8MZr6iUJiRpUpS0LcZ gLK++PdZR/nYx9aFYhHa87cFsm+q62illXJ2onpEeP9a/+0K7ytgN50eZ+HI1PY8+r5ceyjkn8hhQ 8Y/vu4oi2JHJCzBNFwBdOPcp2hLKlBMwG+KUUp7Yu+ZcjV9tkLFyErAyHkdEmO6yudHZSB7DVX+zF QdRLXysg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xLjKK-00000005G0N-1Nqi; Tue, 27 Oct 2026 15:43:04 +0000 Received: from smtp-out2.suse.de ([2a07:de40:b251:101:10:150:64:2]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xLjKH-00000005Fyf-1CLr for kexec@lists.infradead.org; Tue, 27 Oct 2026 15:43:03 +0000 Received: from imap1.dmz-prg2.suse.org (imap1.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 730EA1F397; Tue, 27 Oct 2026 15:42:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1793115778; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=G4U5OOZBCiWmK00YiJ7rS5NugQwh3GpoktzIg7zSeoQ=; b=05qekNvlKxYfyyOuygu8+3pYAJao7K0mXfnE6KXfrx/hkl/80hoFbpRUtsYvyIntVj+oLv vDBzBlXApw5NA8MvS2EofY/+wrChBdJQmmQN51QiMhLZbC3I3VC78D5PCvDL8m+BjSSEKn oYiBO4ys/YhKuauk/eyKmOjh4EoZWNk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1793115778; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=G4U5OOZBCiWmK00YiJ7rS5NugQwh3GpoktzIg7zSeoQ=; b=UkMXw2GdVLvAzlrBoviLIYMkafRvU0AbAnkeAfQewRgHdNSOWLW7fCE2JvkgTu2H96p20s kyxLvfX8bKbMwsDA== Authentication-Results: smtp-out2.suse.de; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=MICKFMxi; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=iONvCRX6 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1793115777; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=G4U5OOZBCiWmK00YiJ7rS5NugQwh3GpoktzIg7zSeoQ=; b=MICKFMxirw3QfXVJtsj5qm3OgphtQWfsLFbgiSg0OMS/b8arLi9n+PrV+qhxz9TU5C0bkw jeaogT/ENx46NUyFExJ06OC/BXyn9+MbrpS8UpOieq6JHf4oSHNsToSOwPR9/6v3GAKTOz YSp6NUt5K6epZ5B6IPGc74IaHM1PeAI= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1793115777; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=G4U5OOZBCiWmK00YiJ7rS5NugQwh3GpoktzIg7zSeoQ=; b=iONvCRX6Pq2+FXsSue5YihO49MeLmlXlcYbh/7SjU82ZnlEfkZN4nY9rbMX+RNwFOgT7VL gTm89YVvu6kVYBBg== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 798B313319; Tue, 27 Oct 2026 15:42:53 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id lULFEX3G4GoZWAAAD6G6ig (envelope-from ); Tue, 27 Oct 2026 15:42:53 +0000 Date: Tue, 27 Oct 2026 15:42:51 +0000 From: Pedro Falcato To: "David Hildenbrand (Arm)" Cc: 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 , 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 26/46] mm/mmu_gather: fix flushing ranges with 4 GiB or larger Message-ID: References: <20261027-fixes_core-v1-0-6f74bec9a5bb@kernel.org> <20261027-fixes_core-v1-26-6f74bec9a5bb@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261027-fixes_core-v1-26-6f74bec9a5bb@kernel.org> X-Rspamd-Queue-Id: 730EA1F397 X-Spam-Level: X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Action: no action X-Spamd-Result: default: False [-12.01 / 50.00]; SUSE_INTERNAL_BYPASS(-9.00)[]; BAYES_HAM(-3.00)[100.00%]; SUSPICIOUS_RECIPS(1.50)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.20)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FREEMAIL_CC(0.00)[linux-foundation.org,cmpxchg.org,kernel.org,linux.dev,tencent.com,google.com,linux.alibaba.com,infradead.org,suse.com,soleen.com,suse.cz,nvidia.com,surriel.com,arm.com,intel.com,redhat.com,gmail.com,suse.de,huaweicloud.com,lge.com,gourry.net,sk.com,ziepe.ca,kvack.org,vger.kernel.org,lists.infradead.org,toxicpanda.com]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; MIME_TRACE(0.00)[0:+]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from]; ARC_NA(0.00)[]; R_RATELIMIT(0.00)[to_ip_from(RL89xh3ijk4gdpeanxbepagf1s)]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; MISSING_XM_UA(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_SOME(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from,2a07:de40:b281:106:10:150:64:167:received]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; RCPT_COUNT_GT_50(0.00)[65]; RCVD_VIA_SMTP_AUTH(0.00)[]; TAGGED_RCPT(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[toxicpanda.com:email,imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo,suse.de:dkim,suse.de:email] X-Spam-Score: -12.01 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261027_084301_895671_BD90018E X-CRM114-Status: GOOD ( 22.17 ) X-Spam-Score: -2.1 (--) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" X-Spam-Status: No, score=-16.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Tue, Oct 27, 2026 at 12:17:46AM +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 flush 16 GiB hugetlb PMDs, 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. > > 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) > --- > 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); > Reviewed-by: Pedro Falcato -- Pedro