From nobody Wed Dec 17 10:46:00 2025 Received: from mail-io1-f73.google.com (mail-io1-f73.google.com [209.85.166.73]) (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 9AB6E1EF395 for ; Thu, 20 Mar 2025 06:39:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742452794; cv=none; b=CliGM5xCknn4AmWEp32WeDhWprAte3uBnClQwu8er3qFpJsiQQfs0K9wBMPdTvCKy1kNwWFf+bZIE8Wm17EfBpDteTHBhwcZVIVrnqwvS8RhG14hbo0f2EEl4HPdY24MIozFQVw5E6fzlvrfxQ3/ddoCgcwNcwZ58u/CE1aYLvg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742452794; c=relaxed/simple; bh=0nPyEUxMVYuWQBfOoZDrSnqSSdM+17gpqIPK/gAVNHM=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=exF6MqSF4BWCAr0xhaHOzcLTTvHrYSCfGMkLEVOeMRjSbly+oukbYEo4hVPK+pL5me64FTGYawT3c2ZUCOQ7YnxwXMzicAZELx2Dyn8sZrWz6EgSiiBMjsaCuSaJlXkVlJjSXHm4l6ZMeP5/k4Rut5BKOdeymDFYhGawH+XZTnc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--avagin.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=QZJE6ZuI; arc=none smtp.client-ip=209.85.166.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--avagin.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="QZJE6ZuI" Received: by mail-io1-f73.google.com with SMTP id ca18e2360f4ac-85b53875729so101745739f.2 for ; Wed, 19 Mar 2025 23:39:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1742452791; x=1743057591; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=AdzZEb8zIh2bnUEQF7HSdB5UkIAPD4MWW1lq1fR+Ug0=; b=QZJE6ZuIim85ftM+Ou5jkI9eOONUT/ijJQKEyGjBnO9KmUKmNVO+WshRmfitp+3bCY P+lbtgHJE2uoNokucBO7fd8U0ev4sfntXnUVCFWSZdx68nytBVr0prR/6IH2JFPAjL+t HlSQaQLTl8FuDfLex9yEkJ649BsUT18vXBhrKNDmWD40tMbJtVTilkvZkNQtv/zeSTR0 VKUVVYko1ov6QG9VwqSKhsp3+aLlbJCkmM8m0VfeOG5+1Wm36vyyDsRtLmt23X1sM51W s4F0ppdr2XodtTI51PsO9gAlK8Wx2QSsz1jWQBpRkQkQh2BCy5GlwWXh2vb4tSzmEwSk 6w9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1742452791; x=1743057591; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=AdzZEb8zIh2bnUEQF7HSdB5UkIAPD4MWW1lq1fR+Ug0=; b=ZLHQopRrli6YnRTNePoCT4l42nHHvFyCIaeOQCRfc7xP+6whPZYOuhgRwvBELcGsiA HRdkbylvho0ShbjOn+gMZF7Dn6IeZn+br2bP06Lx7/wYHzYEKxHOKaasEUcb+0R7AKcp /KU58mV9x596BVx60qKHY6u6FuFUa7e5rLCHaVG+Q3f/Jmp0D6iBA/Swex3dE4WFGH4z tq5y+714ycFrRoJgy0iWyp3bVgkFBUQgLq7NDIYpgWvceNha8zV5Qov8Xac7Y7JtvHq6 6dP/RtZC+DQlXNTY8YT7edtMKcez9VJ5bRsTRQbP/HFVH6SxVvBnI08rkDP+p2nUNGLq KtDw== X-Gm-Message-State: AOJu0Yw7sZ2pezfgoWg9bStUjmAtaN1I3WzB6TANTlmiBNo6Z0++qErn HKlEajnY2uyjLNEjs1s5AKdMu0VyqSG6bVh9+l3zxMXxprbXLrvhP4AI0BbQFo7HKSgo9RGfQmO 3ng== X-Google-Smtp-Source: AGHT+IH9m1sXlXKSr5bFdga9g4GN9qYyPPkoNzV3YUg0gItepaGaNcNSkWbPl4Pwf3Aa3OGUQddoqzehlLk= X-Received: from iobbk13.prod.google.com ([2002:a05:6602:400d:b0:85d:ac99:6c85]) (user=avagin job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6602:4744:b0:85d:9a7a:8169 with SMTP id ca18e2360f4ac-85e13647c3dmr667556939f.0.1742452790845; Wed, 19 Mar 2025 23:39:50 -0700 (PDT) Date: Thu, 20 Mar 2025 06:39:03 +0000 In-Reply-To: <20250320063903.2685882-1-avagin@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250320063903.2685882-1-avagin@google.com> X-Mailer: git-send-email 2.49.0.rc1.451.g8f38331e32-goog Message-ID: <20250320063903.2685882-3-avagin@google.com> Subject: [PATCH 2/2] selftests/mm: add PAGEMAP_SCAN guard region test From: Andrei Vagin To: Lorenzo Stoakes , Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, David Hildenbrand , Shuah Khan , Jonathan Corbet , Andrei Vagin Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Andrei Vagin Add a selftest to verify the PAGEMAP_SCAN ioctl correctly reports guard regions using the newly introduced PAGE_IS_GUARD flag. Signed-off-by: Andrei Vagin --- tools/testing/selftests/mm/guard-regions.c | 53 ++++++++++++++++++++++ 1 file changed, 53 insertions(+) diff --git a/tools/testing/selftests/mm/guard-regions.c b/tools/testing/sel= ftests/mm/guard-regions.c index 0c7183e8b661..24e09092fda5 100644 --- a/tools/testing/selftests/mm/guard-regions.c +++ b/tools/testing/selftests/mm/guard-regions.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -2079,4 +2080,56 @@ TEST_F(guard_regions, pagemap) ASSERT_EQ(munmap(ptr, 10 * page_size), 0); } =20 +/* + * Assert that PAGEMAP_SCAN correctly reports guard region ranges. + */ +TEST_F(guard_regions, pagemap_scan) +{ + const unsigned long page_size =3D self->page_size; + struct page_region pm_regs[10]; + struct pm_scan_arg pm_scan_args =3D { + .size =3D sizeof(struct pm_scan_arg), + .category_anyof_mask =3D PAGE_IS_GUARD, + .return_mask =3D PAGE_IS_GUARD, + .vec =3D (long)&pm_regs, + .vec_len =3D ARRAY_SIZE(pm_regs), + }; + int proc_fd, i; + char *ptr; + + proc_fd =3D open("/proc/self/pagemap", O_RDONLY); + ASSERT_NE(proc_fd, -1); + + ptr =3D mmap_(self, variant, NULL, 10 * page_size, + PROT_READ | PROT_WRITE, 0, 0); + ASSERT_NE(ptr, MAP_FAILED); + + pm_scan_args.start =3D (long)ptr; + pm_scan_args.end =3D (long)ptr + 10 * page_size; + ASSERT_EQ(ioctl(proc_fd, PAGEMAP_SCAN, &pm_scan_args), 0); + ASSERT_EQ(pm_scan_args.walk_end, (long)ptr + 10 * page_size); + + /* Install a guard region in every other page. */ + for (i =3D 0; i < 10; i +=3D 2) { + char *ptr_p =3D &ptr[i * page_size]; + + ASSERT_EQ(syscall(__NR_madvise, ptr_p, page_size, MADV_GUARD_INSTALL), 0= ); + } + + ASSERT_EQ(ioctl(proc_fd, PAGEMAP_SCAN, &pm_scan_args), 5); + ASSERT_EQ(pm_scan_args.walk_end, (long)ptr + 10 * page_size); + + /* Re-read from pagemap, and assert guard regions are detected. */ + for (i =3D 0; i < 5; i++) { + long ptr_p =3D (long)&ptr[2 * i * page_size]; + + ASSERT_EQ(pm_regs[i].start, ptr_p); + ASSERT_EQ(pm_regs[i].end, ptr_p + page_size); + ASSERT_EQ(pm_regs[i].categories, PAGE_IS_GUARD); + } + + ASSERT_EQ(close(proc_fd), 0); + ASSERT_EQ(munmap(ptr, 10 * page_size), 0); +} + TEST_HARNESS_MAIN --=20 2.49.0.rc1.451.g8f38331e32-goog