From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj2-f13.google.com (mail-pj2-f13.google.com [74.125.227.141]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E32B43E068 for ; Sat, 26 Sep 2026 12:42:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.227.141 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790426525; cv=none; b=b+AtqS4Tk0xQniRUNc/H5UWkfCEQRjJ7fze3MAp4JH9CBD4+sXt3Ud+LdsyzwCD1w+qTWZ4abm15/bW0Ai8Mwh4o4ikrxzcsrC9sn/qXCfDfzC/qcBQy/Z/jUk6MD7v8/LckESfK3d6yhGbRPqbYCZSyv1XeZSKQ08WuDDhPiz8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790426525; c=relaxed/simple; bh=UbB5IgdtGCndW6UG3N7bTvImpV7aVcAWAKDDVClg/oQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=THG0YSMqZMlRN+5G0g8YuiR0fxRyaVXNUrKDZEL7wMNNsZ+xl9hgObJsh5tsZ8aBTsDbPgURB4o+JKjgKN2+9Jw5/gr65LmodQCew1xeB8M6thCI6/z148Q9rDBjV7qYaL0GrlcVVqgGix8NDH4z6XFjg1ddx0y+MoFmfixpRvE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=rSfJ8Fuf; arc=none smtp.client-ip=74.125.227.141 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rSfJ8Fuf" Received: by mail-pj2-f13.google.com with SMTP id 98e67ed59e1d1-39dacf053eeso885441a91.2 for ; Sat, 26 Sep 2026 05:42:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1790426522; x=1791031322; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=UuPio8yVnMFS6iISF91e2TRt3XkbnhyD4KTt+debFho=; b=rSfJ8Fuft0MPx8LymPU0nIrdUIr3AvbjxXo5E6RwvYaoN+6QXU65kItJUL4Mup86RL m+9Rg1qu37QubB7f2jFzuH4fAbR9ablKrXqRKgnFtsm7wph1dpgazJv3r9A32gFr9AX1 /3Z0RdYNRKJVh2vV6tde+YbScxno4iRgn7qpROeK7HBqmgM2x9g+rZSeipsQAHrDBQ/v U9kIR4D1/PXYybndFfYItoBuhYXqf4jM0KF4LRzBVWlld5ki3OSMhrQ5h7FI5dh9BjSI gDtVO05nfD7PhUE74fbN+K9g5eBsB5POfVCe7clM3kGQUariRv4gMklvRch6wBZWIVhW AuRA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790426522; x=1791031322; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=UuPio8yVnMFS6iISF91e2TRt3XkbnhyD4KTt+debFho=; b=EbDyWcB9D9i6CbzxfNHkkFT3IMa9q4sXdUnFeVctz9sw4EMcFXEYDplAVF5VZJzFvG rdnRDemCrgEBIAxqgUI44rOzSSXZ40Tk9eMwPXXhMy/9z+hHcj2Nxrb8HspSS2Y2+ugh 5yYqC1UmYmN1hBa2M8M7G//OHc5JiKzmlrNQdvLlZzOZHSvtQ9HoobOOZoLLQ5W0Vdtu Mewb96/4H895oPPdRAnkMXgHVkuy0zio5nkAG0RpJtBT0WcFADvPJldTnn1YovFs/ykA NJCjqKe8INxifxrGmKYH0N922mD8cFNIcw46lmRaCnWYuiXCgbcYUIvK0jvx201NjICz apYA== X-Forwarded-Encrypted: i=1; AKwUvBz4e+wgmFG+EMVcRdE90hnUUsnGOAkTCGLdCNxYb7U8RjvoLbhdOKZG48bQwBOES6AN1o1BzwJPDcrRlBs=@vger.kernel.org X-Gm-Message-State: AFq9FYKOvr0Ce6ywzScrBm9GFebtzuNyE/Sjo59zadfPcV5TLDgNKVDn 614DAOTsx7LF+2DExL1byPcCmW4fQ75LANdrvBC231rNAk3as3Wg0Vs= X-Gm-Gg: AYBFou3guzXHmFIYa9zFCob+MH9fQRBCI00VEohSjzgAyP7bnLwWA3LsE+sMmFNtLtC gPEXWdG53Qn5TgCnJtoi+a3X1HDb8Nwnlu/QnhI24LQjTibo8VD+fRoAvaiO47Q30PNroBqArSo 6SORGQRJB1Elsg5DAgt1UdK4EbctdDQlqVcMJ0XFGqu3uCrVjtnBgGBYKhRxZ1ksfoKhUv+bbMO rIE4FJK1kbRM8pebF3hYmiv0bNfdTDnfQT372nM5UI7BH5xCo6190yqvVdKc+eD/c1ltN88ohkb p7FsfIngPsify+vzKQaik0zEKAXvUU6Y4O/7hO3X2ZhTxuIYRNadSdbuMQao3mfqgD/0bC4iBfj abI0p0igVBy+ok8PXaIVI52NwOzdMjIX0mYbOsVtxvpvk2HZ4fO95fy5V44YEbfEtzoa/tl9xQ+ lUmJErKHftiIyyjkgKxHvC4tXsCOCIWPUOlb919bS7xvVoo/kpGgAJNQhvopDJHqMsBppEgASl0 QesLp2XRl79D4vCzUNmXxxH X-Received: by 2002:a17:90a:38e4:b0:3a0:b223:6830 with SMTP id 98e67ed59e1d1-3a0b2236c1dmr2901997a91.7.1790426522302; Sat, 26 Sep 2026 05:42:02 -0700 (PDT) Received: from ydg-Zenbook-14-UM3406GA ([211.230.25.193]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3a0cd1c4ec9sm5965212a91.16.2026.09.26.05.41.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 26 Sep 2026 05:42:01 -0700 (PDT) From: Donggeun Yoo To: akpm@linux-foundation.org, rppt@kernel.org Cc: peterx@redhat.com, surenb@google.com, aarcange@redhat.com, david@kernel.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, mhocko@suse.com, shuah@kernel.org, kirill@shutemov.name, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, donggeunyoo.kernel@gmail.com Subject: [PATCH v3 2/2] selftests/mm: add tests for UFFDIO_MOVE of a uffd-protected swap entry Date: Sat, 26 Sep 2026 21:41:45 +0900 Message-ID: <20260926124145.2878520-3-donggeunyoo.kernel@gmail.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260926124145.2878520-1-donggeunyoo.kernel@gmail.com> References: <20260926124145.2878520-1-donggeunyoo.kernel@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Move a swapped-out page out of a write-protected or RWP-protected area into a destination registered for missing faults only, and read pagemap bit 57 at the destination. The destination was never protected, so the bit must be clear. Assisted-by: LLM Signed-off-by: Donggeun Yoo --- tools/testing/selftests/mm/uffd-unit-tests.c | 84 ++++++++++++++++++++ 1 file changed, 84 insertions(+) diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c index ef9b3956bdcfd..580178630eded 100644 --- a/tools/testing/selftests/mm/uffd-unit-tests.c +++ b/tools/testing/selftests/mm/uffd-unit-tests.c @@ -2037,6 +2037,75 @@ static void uffd_move_pmd_split_test(uffd_global_test_opts_t *gopts, uffd_test_a uffd_move_pmd_handle_fault); } +/* + * Moving a swapped-out page out of a write-protected or RWP-protected area + * must not carry the uffd bit into a destination registered for missing + * faults only: such a bit is never cleared afterwards, so pagemap keeps + * reporting the page as uffd-tracked. + * + * Needs a swap device; skipped if MADV_PAGEOUT cannot evict the page. + */ +static void uffd_move_swap_test_common(uffd_global_test_opts_t *gopts, + bool rwp) +{ + unsigned long page_size = gopts->page_size; + struct uffdio_move move = { }; + int pagemap_fd; + + if (rwp) { + if (uffd_register_rwp(gopts->uffd, gopts->area_src, page_size)) + err("register src failure"); + } else if (uffd_register(gopts->uffd, gopts->area_src, page_size, + false, true, false)) { + err("register src failure"); + } + if (uffd_register(gopts->uffd, gopts->area_dst, page_size, + true, false, false)) + err("register dst failure"); + + if (rwp) + rwprotect_range(gopts->uffd, (unsigned long)gopts->area_src, + page_size, true); + else + wp_range(gopts->uffd, (unsigned long)gopts->area_src, + page_size, true); + + pagemap_fd = pagemap_open(); + if (madvise(gopts->area_src, page_size, MADV_PAGEOUT)) + err("MADV_PAGEOUT"); + if (!pagemap_is_swapped(pagemap_fd, gopts->area_src)) { + uffd_test_skip("MADV_PAGEOUT did not swap the page; is swap enabled?"); + goto out; + } + + move.dst = (unsigned long)gopts->area_dst; + move.src = (unsigned long)gopts->area_src; + move.len = page_size; + if (ioctl(gopts->uffd, UFFDIO_MOVE, &move)) + err("UFFDIO_MOVE"); + + if (pagemap_get_entry(pagemap_fd, gopts->area_dst) & PM_UFFD_WP) + uffd_test_fail("uffd bit moved into an area registered for missing faults only"); + else + uffd_test_pass(); +out: + close(pagemap_fd); + uffd_unregister(gopts->uffd, gopts->area_src, page_size); + uffd_unregister(gopts->uffd, gopts->area_dst, page_size); +} + +static void uffd_move_swap_wp_test(uffd_global_test_opts_t *gopts, + uffd_test_args_t *targs) +{ + uffd_move_swap_test_common(gopts, false); +} + +static void uffd_move_swap_rwp_test(uffd_global_test_opts_t *gopts, + uffd_test_args_t *targs) +{ + uffd_move_swap_test_common(gopts, true); +} + static bool uffdio_verify_results(const char *name, int ret, int error, long result) { @@ -2359,6 +2428,21 @@ uffd_test_case_t uffd_tests[] = { .uffd_feature_required = UFFD_FEATURE_MOVE, .test_case_ops = &uffd_move_test_pmd_case_ops, }, + { + .name = "move-swap-wp", + .uffd_fn = uffd_move_swap_wp_test, + .mem_targets = MEM_ANON, + .uffd_feature_required = UFFD_FEATURE_MOVE | + UFFD_FEATURE_PAGEFAULT_FLAG_WP, + .test_case_ops = &uffd_move_test_case_ops, + }, + { + .name = "move-swap-rwp", + .uffd_fn = uffd_move_swap_rwp_test, + .mem_targets = MEM_ANON, + .uffd_feature_required = UFFD_FEATURE_MOVE | UFFD_FEATURE_RWP, + .test_case_ops = &uffd_move_test_case_ops, + }, { .name = "wp-fork", .uffd_fn = uffd_wp_fork_test, -- 2.53.0