From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 B00D248034B; Wed, 12 Aug 2026 17:19:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786555158; cv=none; b=YrjU1GyR4EFP8qsVpvD1jJO0d1jUq2pdyRLGMrFZXKiTSlcLIhbEMrDtJjWHZX264rHroNpL9g1VIfwb6pQM06Exy+IStegaYzu1ydoVZAUkwkxXJXCftpQnkfiepdOGqCgK/cA3UuGzjAP3jiJatQVf8caeFYNg7hZO9OUyyng= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786555158; c=relaxed/simple; bh=GYOAjHhYuitzQfTZJr4bgHpDP23FDcd0VUw8GxZhKJk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=t3VsySHuq8cH1brZfsjvb71S59AeI/QMlgS6xghxUoSLgd7i0nfthueumQPuB/N0x5EinXi2yFeNJnPZywikVhKBHVpFeSSvhl+XkXPjO5GQbrmVXtYYghFZbM8ozlNqIBA3VFz7f1kPa/KV+Rv5t0RwFKVY+E0Hz0nPPkPLcmo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hLWxCl64; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hLWxCl64" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 40E471F000E9; Wed, 12 Aug 2026 17:18:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786555157; bh=8WxyeD/4K/o06qOFzP7l98EIPHkrp93Cvie3fdx+YOA=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=hLWxCl64FwqEYTiMqoHVw+thTGYp72pt2VffGqLy69crUuSqbNDx2idc8hBpx8w0J P3JAeDvIcyVd8+wRt0BAw61Hu6zDJOLsFFODqNhfCxEZsSTiJJN/2Y7LuwsSc8cLNb 23NQDQc7YkGWiKnFaMI30ynO5fSaGB2yZ5FxirgtAYQpsvPUp6nIgZnNpkkp897Ovn wki1zPDK9TzVk+FQBO6+i7O13PJZeE0JzZQk+tKDMDirc7GfEZNVWzXyD3BCYeCmjV I8oFpfyH/8yCYBIBereVnICPY6/Yvq4V2ZyoWh25BXSNfIhIKtgzVZO3swyC/kPN12 wnhjGkkwdbPgA== Message-ID: Date: Wed, 12 Aug 2026 19:18:56 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 19/20] tools/testing/vma: add test to assert MAP_PRIVATE-/dev/zero is anon To: "Lorenzo Stoakes (ARM)" , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Pedro Falcato , "Matthew Wilcox (Oracle)" , Jan Kara , Miaohe Lin , Naoya Horiguchi , Rik van Riel , Harry Yoo , Lance Yang , Kees Cook , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Usama Arif , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Peter Xu , Xu Xin , Chengming Zhou , Arnd Bergmann , Greg Kroah-Hartman , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Sven Schnelle , Alex Deucher , =?UTF-8?Q?Christian_K=C3=B6nig?= , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Boris Brezillon , Steven Price , Liviu Dudau , Huang Rui , Matthew Auld , =?UTF-8?Q?Thomas_Hellstr=C3=B6m?= , Rodrigo Vivi , Masami Hiramatsu , Oleg Nesterov , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , Jason Gunthorpe , John Hubbard , Muchun Song , Oscar Salvador , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Youngjun Park Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, kvm@vger.kernel.org, linux-s390@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-perf-users@vger.kernel.org, linux-trace-kernel@vger.kernel.org References: <20260806-b4-scalable-cow-virt-pgoff-v4-0-ab318a350404@kernel.org> <20260806-b4-scalable-cow-virt-pgoff-v4-19-ab318a350404@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/6/26 22:21, Lorenzo Stoakes (ARM) wrote: > Now we've made MAP_PRIVATE-mapped /dev/zero mappings truly anonymous, add a > VMA userland test to assert that this is the case and everything is as > we would expect for an anonymous mapping. > > Signed-off-by: Lorenzo Stoakes (ARM) > --- > tools/testing/vma/include/dup.h | 1 + > tools/testing/vma/tests/mmap.c | 50 +++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 51 insertions(+) > > diff --git a/tools/testing/vma/include/dup.h b/tools/testing/vma/include/dup.h > index aee36707abdd..41203b1c2323 100644 > --- a/tools/testing/vma/include/dup.h > +++ b/tools/testing/vma/include/dup.h > @@ -20,6 +20,7 @@ struct task_struct *get_current(void); > > #define MAJOR(dev) ((unsigned int) ((dev) >> MINORBITS)) > #define MINOR(dev) ((unsigned int) ((dev) & MINORMASK)) > +#define MKDEV(ma, mi) (((ma) << MINORBITS) | (mi)) > > #define S_IFMT 00170000 > #define S_IFCHR 0020000 > diff --git a/tools/testing/vma/tests/mmap.c b/tools/testing/vma/tests/mmap.c > index c85bc000d1cb..ebe01362e530 100644 > --- a/tools/testing/vma/tests/mmap.c > +++ b/tools/testing/vma/tests/mmap.c > @@ -45,7 +45,57 @@ static bool test_mmap_region_basic(void) > return true; > } > > +static int dummy_mmap_prepare(struct vm_area_desc *desc) > +{ > + return 0; > +} > + > +static bool test_pure_anon_dev_zero(void) > +{ Ah, just one comment: should we call this something like "test_map_private_dev_zero", at least that'd be clearer for me. -- Cheers, David