From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 64C04142E86 for ; Wed, 6 Nov 2024 00:58:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730854737; cv=none; b=qPo71PDhI52j35kq6Q8ER1JvZotzj5PK/AgrmpbykdiN7ggvquVeEw4C9qH7E5MdcgnTUCEZ817sn0BzggirXDIg8Y7oe04c3jqCQnIOTrSFLEPWmPH37gmRBztw/dbwJK0U7q0bvy4e9rI5fFLeWWsTdV+7FuQf73KVR8sRzEs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730854737; c=relaxed/simple; bh=eF+qWJh9MBOj0Ss9+zbwxEJSRWYTCwogzQzJuxg1oRI=; h=Date:To:From:Subject:Message-Id; b=JpnTPG/f8WOQpndhpa4y+OKBrfI4byt34aiRHqAH3W2ez1E7DRTG/krl+p1soJWUksOMTGp3d7tZfgt2dznY4N6CCFHLscRvziI0c2te20pL5nkOLNAw+L30O7hBGT7Lpu+Qk7+PR/K47t3/pfELYmzPOAKZ4ikSA8rkhVLIooQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=1MckXdk3; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="1MckXdk3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 30481C4CECF; Wed, 6 Nov 2024 00:58:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1730854737; bh=eF+qWJh9MBOj0Ss9+zbwxEJSRWYTCwogzQzJuxg1oRI=; h=Date:To:From:Subject:From; b=1MckXdk3p73XFkn5v9qvHgahHaOl457MGupOHChth5etz63ErdFgquYoDk3DwrBMw EaBGUvb1T+gOIGvhzp5d4ITVeI3C+5hhM/1cNran5GQHNKmFeVIUZjxMTV/Nj8RMtc b8sP4SGPdnigPVF1XaKOCfAgQ7MxfPPdk8vwpngY= Date: Tue, 05 Nov 2024 16:58:56 -0800 To: mm-commits@vger.kernel.org,willy@infradead.org,vishal.moola@gmail.com,ryan.roberts@arm.com,rppt@kernel.org,peterx@redhat.com,muchun.song@linux.dev,hughd@google.com,david@redhat.com,zhengqi.arch@bytedance.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-userfaultfd-move_pages_pte-use-pte_offset_map_rw_nolock.patch removed from -mm tree Message-Id: <20241106005857.30481C4CECF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm: userfaultfd: move_pages_pte() use pte_offset_map_rw_nolock() has been removed from the -mm tree. Its filename was mm-userfaultfd-move_pages_pte-use-pte_offset_map_rw_nolock.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Qi Zheng Subject: mm: userfaultfd: move_pages_pte() use pte_offset_map_rw_nolock() Date: Thu, 26 Sep 2024 14:46:24 +0800 In move_pages_pte(), we may modify the dst_pte and src_pte after acquiring the ptl, so convert it to using pte_offset_map_rw_nolock(). But since we will use pte_same() to detect the change of the pte entry, there is no need to get pmdval, so just pass a dummy variable to it. Link: https://lkml.kernel.org/r/1530e8fdbfc72eacf3b095babe139ce3d715600a.1727332572.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Reviewed-by: Muchun Song Cc: David Hildenbrand Cc: Hugh Dickins Cc: Matthew Wilcox Cc: Mike Rapoport (Microsoft) Cc: Peter Xu Cc: Ryan Roberts Cc: Vishal Moola (Oracle) Signed-off-by: Andrew Morton --- mm/userfaultfd.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) --- a/mm/userfaultfd.c~mm-userfaultfd-move_pages_pte-use-pte_offset_map_rw_nolock +++ a/mm/userfaultfd.c @@ -1135,7 +1135,7 @@ static int move_pages_pte(struct mm_stru spinlock_t *src_ptl, *dst_ptl; pte_t *src_pte = NULL; pte_t *dst_pte = NULL; - + pmd_t dummy_pmdval; struct folio *src_folio = NULL; struct anon_vma *src_anon_vma = NULL; struct mmu_notifier_range range; @@ -1146,7 +1146,14 @@ static int move_pages_pte(struct mm_stru src_addr, src_addr + PAGE_SIZE); mmu_notifier_invalidate_range_start(&range); retry: - dst_pte = pte_offset_map_nolock(mm, dst_pmd, dst_addr, &dst_ptl); + /* + * Use the maywrite version to indicate that dst_pte will be modified, + * but since we will use pte_same() to detect the change of the pte + * entry, there is no need to get pmdval, so just pass a dummy variable + * to it. + */ + dst_pte = pte_offset_map_rw_nolock(mm, dst_pmd, dst_addr, &dummy_pmdval, + &dst_ptl); /* Retry if a huge pmd materialized from under us */ if (unlikely(!dst_pte)) { @@ -1154,7 +1161,9 @@ retry: goto out; } - src_pte = pte_offset_map_nolock(mm, src_pmd, src_addr, &src_ptl); + /* same as dst_pte */ + src_pte = pte_offset_map_rw_nolock(mm, src_pmd, src_addr, &dummy_pmdval, + &src_ptl); /* * We held the mmap_lock for reading so MADV_DONTNEED _ Patches currently in -mm which might be from zhengqi.arch@bytedance.com are