From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 97B35C982FA for ; Tue, 22 Sep 2026 12:35:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6A9456B00A1; Tue, 22 Sep 2026 08:35:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 631FF6B00A2; Tue, 22 Sep 2026 08:35:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 521106B00A4; Tue, 22 Sep 2026 08:35:12 -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 E94F96B00A1 for ; Tue, 22 Sep 2026 08:35:11 -0400 (EDT) Received: from smtpin03.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 9088DA4AD6 for ; Tue, 22 Sep 2026 12:35:11 +0000 (UTC) X-FDA: 85241343222.03.24345EE Received: from mta1.migadu.com (out-223.mta1.migadu.com [95.215.58.223]) by imf27.hostedemail.com (Postfix) with ESMTP id 6088A40006 for ; Tue, 22 Sep 2026 12:35:09 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=cwU8b8G2; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf27.hostedemail.com: domain of usama.arif@linux.dev designates 95.215.58.223 as permitted sender) smtp.mailfrom=usama.arif@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1790080509; 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=UooEYY3XSUXc5Zv1HmaYpLhPrMN8hkGySW7d8Ioqs6A=; b=ChQaa5rBwaTmSpdpIp9+DxCBPRmkHiPA0GahcHI3E9aPkNCaWjMjTncfbAvIK5TmXLgIsb 6E/qd1ZwOzY8wQqr1TKxj3WlQ6aEsnV0vu3VWyz03WBB68ewDCcRtZ6YtKJyR4o8xj7pRG sdYa2pXBrnSp7qZIzCwHQt998Ki4lho= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=cwU8b8G2; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf27.hostedemail.com: domain of usama.arif@linux.dev designates 95.215.58.223 as permitted sender) smtp.mailfrom=usama.arif@linux.dev ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790080509; b=jKvj+tbml7tAvu6+7EoRNZWsC64KBUaibUl2Ym0lQ6fW4ylKy4eBdgm3/qr9I03Qq/GQsw N6ZQoo0GLXmGkbMmnSLfIlw2HQ9gnK5WFAFDIWG5qpjWvdNxHO2unc3Q6yiX52/dc4TGmw hjupPM+ElpUjCWYV2oOjPDk1ymEqnW8= X-Envelope-To: linux-mm@kvack.org DKIM-Signature: a=rsa-sha256; bh=Xwtckas4LnrLCXkCKb5n3gLZW22/ubZm4385L/A1/Us=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1790080507; v=1; x=1790685307; b=cwU8b8G2j89LJqxIjxBtNYWYqjPo1PayZjH83zRHeqVgP6VfEri3Wf9IKp0tt6KmP4wI0xZN hb2CW7siSn7YnPGfiVFzdDT/X60o4CFcNtpju2LGGRLnAkd098QFrtxO0eGrlRmbeMoydTw+Vki T50i5J46t+verlulVm31rdoU= X-Envelope-To: linux-mm@kvack.org Received: by smtp.migadu.com with ESMTPS id 887b51e9a353e5f0; Tue, 22 Sep 2026 12:35:06 +0000 X-Mizu-Trace-ID: 887b51e9a353e5f0 X-Migadu-Flow: FLOW_OUT Message-ID: <93e71e27-86d7-4853-bbd2-756ac137a925@linux.dev> Date: Tue, 22 Sep 2026 13:34:59 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RESEND v7 02/29] arm64: mm: add PMD swap-exclusive helpers To: "David Hildenbrand (Arm)" , Andrew Morton , chrisl@kernel.org, kasong@tencent.com, ljs@kernel.org, ziy@nvidia.com, linux-mm@kvack.org Cc: ying.huang@linux.alibaba.com, Baoquan He , willy@infradead.org, youngjun.park@lge.com, hannes@cmpxchg.org, riel@surriel.com, shakeel.butt@linux.dev, alex@ghiti.fr, kas@kernel.org, baohua@kernel.org, dev.jain@arm.com, baolin.wang@linux.alibaba.com, Nico Pache , "Liam R. Howlett" , ryan.roberts@arm.com, Vlastimil Babka , lance.yang@linux.dev, linux-kernel@vger.kernel.org, nphamcs@gmail.com, shikemeng@huaweicloud.com, yosry@kernel.org, qi.zheng@linux.dev, luizcap@redhat.com, kernel-team@meta.com, Catalin Marinas , Will Deacon References: <20260914122950.3283997-1-usama.arif@linux.dev> <20260914122950.3283997-3-usama.arif@linux.dev> <35e42ccc-df8f-4703-b10d-f7c96b263e98@kernel.org> Content-Language: en-US From: Usama Arif In-Reply-To: <35e42ccc-df8f-4703-b10d-f7c96b263e98@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: nyoq6jppndpcabtfdh987yhftx7w4c65 X-Rspam-User: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 6088A40006 X-HE-Tag: 1790080509-902549 X-HE-Meta: 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 6+GFZ3pi RQac8kR7F4rhPxjNC3ktzcB1e8SjDCy925Axu8XN9/o6fgLGCmK/ZD/s818YUjUIwLyzJF0v8Bs3TQ4HrHMST6oCvErV9ddG1ndz7ndgietLGZRmTyx8Fbfzm2uIS0ZrQforc5GvR2xj9LftxYBqZ2soeRESHD+Wznb1CNkITuhBSIZLQICehjmWh2LvNksetR64UlXmCfQxUzXpYcRMya09P2Hc08c/lziaOwWrrWd4Gp2ZK1RN8Sj1cby9jh4LEnv/paOKgJGhrutZSLGRCG3X3yOvrn4Pe6q9HXhDueA3Uzn0VG2EI3dzs06m/txQ6T+RMcWlN+NqrQGKKzpIMCgnS6tOVCT1A1HdQDXYgA4pWldA= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 18/09/2026 22:11, David Hildenbrand (Arm) wrote: > On 9/14/26 14:27, Usama Arif wrote: >> A later patch keeps a PMD-mapped anonymous THP mapped by a PMD across the >> swap round-trip, so PG_anon_exclusive now has to survive in a swap PMD and >> not just in a swap PTE. >> >> arm64 encodes a swap PMD exactly like a swap PTE, so the new helpers wrap >> the PTE ones and reuse PTE_SWP_EXCLUSIVE. >> >> Cc: Catalin Marinas >> Cc: Will Deacon >> Signed-off-by: Usama Arif >> --- >> arch/arm64/include/asm/pgtable.h | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h >> index e89ec5f4787b4..d3f53a601aed3 100644 >> --- a/arch/arm64/include/asm/pgtable.h >> +++ b/arch/arm64/include/asm/pgtable.h >> @@ -599,6 +599,12 @@ static inline int pmd_protnone(pmd_t pmd) >> #define pmd_swp_clear_uffd(pmd) \ >> pte_pmd(pte_swp_clear_uffd(pmd_pte(pmd))) >> #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */ >> +#ifdef CONFIG_ARCH_HAS_PMD_SOFTLEAVES >> +#define pmd_swp_exclusive(pmd) pte_swp_exclusive(pmd_pte(pmd)) >> +#define pmd_swp_mkexclusive(pmd) pte_pmd(pte_swp_mkexclusive(pmd_pte(pmd))) >> +#define pmd_swp_clear_exclusive(pmd) \ >> + pte_pmd(pte_swp_clear_exclusive(pmd_pte(pmd))) >> +#endif > > Why do we #ifdef that here, but not the uffd-wp swp PMD helper? > uffd-wp is gated on CONFIG_HAVE_ARCH_USERFAULTFD_WP. If I removed the CONFIG_ARCH_HAS_PMD_SOFTLEAVES guards above, when THP=n, arm64 will use the generic macro which is wrong. I tried building uffd-wp swp with just ARCH_HAS_PMD_SOFTLEAVES guard and I got the build error mm/page_table_check.c:232:20: error: implicit declaration of function 'pmd_swp_uffd' we will probably need a separate patch like: #ifdef CONFIG_ARCH_HAS_PMD_SOFTLEAVES static inline bool pmd_softleaf_uffd(pmd_t pmd) { return pmd_swp_uffd(pmd); } #else static inline bool pmd_softleaf_uffd(pmd_t pmd) { return false; } #endif to avoid the above build error.