From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f176.google.com (mail-pl1-f176.google.com [209.85.214.176]) (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 8782F3DE426 for ; Mon, 31 Aug 2026 23:29:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788218963; cv=none; b=mb5Q/dtjPioPYZXnCOJL8xqvhP1/fdXOb4qBFwKN94qzCkfXEbTogVLz1cFT4tRtaGIHN7iqsGbZ5Eyde1uAeJ6/GQO6qdUBY5zuFj3848toThsGywluxJ5n8OFJJnwYhIpI3Vk803zMvXc8Z0NhyrjW+HfpMiLyJ7P/f+1iMmc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788218963; c=relaxed/simple; bh=+i2m/TMTDSfo6u7b+++PuDvubIKwXr72/RqiL6m6Dis=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=N9S40lLwpuXPqGVVHLf0Wbo/eLfq4YKn1/Mc5hB1q11mdeiAnq1JIExTYyL2YIyNIqezJ0+eDF/Zs93vnDrSqcMOaoJxymDAE/Z0J1YjofZuWCutiMMpIhuoXQQyj4u/9diHSS6yMAxc+WxgrSwVwz8CZPtSFhEprS1rK3LOplA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=CoUrpoGr; arc=none smtp.client-ip=209.85.214.176 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=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CoUrpoGr" Received: by mail-pl1-f176.google.com with SMTP id d9443c01a7336-2d3b445a84fso23075ad.1 for ; Mon, 31 Aug 2026 16:29:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1788218962; x=1788823762; darn=vger.kernel.org; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to:content-type; bh=/n3fvUgG6MbykCjQ/yhTPU59M7rXcCUC3WVx+XsgKas=; b=CoUrpoGrLQSGUX080qGjxFrjdRvsrDFUBXmb6ng5+9BHV7xh3Xd+uyrJmG8rCIANEW i3YEN7QNpvAcAJcAXLFbqZNCz7YU6FvxfiTaCmVM+nxXu10sDg3IIJxbsLb0tCw3ITgS bSaQnAY3ydYnZ9HJLZqTKehabxmR89Dw+TnmHrfS3abOKfm2bxTM8mmY5mB+i1MKp2qL NGYvLPppKM+H4+6dSUtnh7WMqED2vR+i4/BZTBbg2O6mGWHYf5+b2NhhvRWy8rwF4IbA 1+fvphekifp/l7eTBmrPvc6PqbwO/AbPEVR4L076/1yyLnW1hUdJNzyQyVSMgbKT/tVi s9Lg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788218962; x=1788823762; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:from :date:x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=/n3fvUgG6MbykCjQ/yhTPU59M7rXcCUC3WVx+XsgKas=; b=Rjdv4TMWXow/5fywm6WdVTp/wj2+xTF+LbjR8FeyoszfQzSvj26Q5hrvEdXgPJX4VY tkct93Z751oWNLxzgVZJMuL3lWples+gG5xvyZB0ICgYS5oVoptbWt/ffMoUAG3PjQZQ YnbOPYSmUXdesHvZZqbaK565xChD8WXKSUjdKZ6YHxqypfQX6FGDJTbIoktAbnu+ZEW8 lIGSSBX+0XE9aOMhomVTX7G/6ZaUg2M6DtpwW3sGBNVmiU4ehb3TyKj73KiUbcr3CFt7 pFH0SU2pAK1nswAUlO2Y4t386kMR4wZ6ipu4GbmInl7BBgDsjKUdJTaTVbo9Cl5ecVjk ptLA== X-Forwarded-Encrypted: i=1; AKwUvByTKxnBxJJ1BlN3Oe+2KA+4SSS4lZipdFGnaLFiSHcKtgw/0yrIFo7BVVi9b2zXrX0c7Dhg7h2QXc+TcaM=@vger.kernel.org X-Gm-Message-State: AFuF++n+yffgOg61dIwKHAkNECxzZc1m3ctKDXhi5N7B9TbA6kn9qFX5 pAXTVYjkCeECAT6af+uVoxlUJzx1Ey5aXSdcV16c0qDEh73kIU6ynm5vtDfroohBfg== X-Gm-Gg: AYBFou3a1RxuelPq2ApunQj3I48cSF2uwV5ViCxCuXcGe0zuHSdJxGyVslYfO6Egi5F xvHNnxCUKTB+4qh7rB4QuKRFIqpjOLXBZ/oIiN+pOfLzrl+JrvFj8f2K895F/5xjP+VSBwTIhJL LwOkXB0pRx8XZyIhDTJNSyrkDglnoz8jK++r4ZPJxlcG7+emFHIB5KHd8T6fNx0Ruy3rJFFoLCH J5af8EFtyz+Bs5m1rjtykz+iXlMVNgl560gKuTtTAvY6+OwY883n/xhJuvr5bvlE/IXsmHGlwoK k72P/VN+ao9hD0UecGkVft00NloULY0EorpsT/zohjuCqdH1NQJSuXhiBcs3CzPWvWxpkWIMcKH DW741rQi2MtQE6GU6EgTmDhPz8iqvTMnZg5NWgKpJrS2URAFmqLwNhzRvF4t3/6lEw6/7TUmUnn TbEgm0yluPqcGp02J2Ujy+WzezZ7Da+7J6Vt3ZC4Avw91C9e9sf1FQt0dpW1erO1eJ+mmIN7l/Z J9tDm+gqPKYVch7keiupbRXQJChHZ4XAT2XlLl8hEBMfXKYeSXliqD4yk7FS6ae6bJeL6wtc5Wd JxI+HciQOFdQIIJpUQ== X-Received: by 2002:a17:903:2290:b0:2c7:f688:f22f with SMTP id d9443c01a7336-2d959ba8671mr1247175ad.13.1788218961331; Mon, 31 Aug 2026 16:29:21 -0700 (PDT) Received: from google.com (193.67.125.34.bc.googleusercontent.com. [34.125.67.193]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-85be6377472sm154420b3a.19.2026.08.31.16.29.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 31 Aug 2026 16:29:20 -0700 (PDT) Date: Mon, 31 Aug 2026 23:29:16 +0000 From: Carlos Llamas To: Suren Baghdasaryan Cc: Alice Ryhl , Andrew Morton , dave.hansen@linux.intel.com, Liam.Howlett@oracle.com, ljs@kernel.org, david@redhat.com, willy@infradead.org, shakeel.butt@linux.dev, vbabka@kernel.org, jannh@google.com, arve@android.com, christian@brauner.io, tkjos@android.com, dsahern@kernel.org, davem@davemloft.net, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org Subject: Re: [PATCH v6 0/5] mm: Unconditional per-VMA locks and cleanups Message-ID: References: <20260813193433.3318288-1-surenb@google.com> <20260829185625.f5ee1b2931818843a78af88d@linux-foundation.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Mon, Aug 31, 2026 at 04:19:39PM -0700, Suren Baghdasaryan wrote: > On Mon, Aug 31, 2026 at 3:27 PM Carlos Llamas wrote: > > > > On Mon, Aug 31, 2026 at 11:13:16AM +0000, Alice Ryhl wrote: > > > On Sat, Aug 29, 2026 at 06:56:25PM -0700, Andrew Morton wrote: > > > > On Thu, 13 Aug 2026 12:34:28 -0700 Suren Baghdasaryan wrote: > > > > > > > > > v2 version of this patchset [1] was written by Dave Hansen and per his > > > > > request, I'm taking over this series. > > > > > > > > > > tl;dr: Make per-VMA locks available in all configs. Simplify some > > > > > of the per-VMA lock users now that they can rely on them being > > > > > always available. > > > > > > > > It's been 2+ weeks so perhaps a refresh-and-remind would be helpful. > > > > > > > > But it applies well enough and is adequately reviewed so I put it in > > > > there for testing, thanks. > > > > > > > > AI review might have found a couple of pre-existing binder bugs: > > > > > > > > https://sashiko.dev/#/patchset/20260813193433.3318288-1-surenb@google.com > > > > > > > > and a small rusty thing which you might wish to attend to. > > > > > > The binder bug is not actually a bug. When using VM_MIXEDMAP and > > > vm_insert_page(), the vma takes a refcount on the page, so there is no > > > use-after-free even if free_page() is invoked without removing it from > > > the vma. > > > > Exactly! I agree the refcount on the page would prevent the UAF. > > > > However, we should still reject mremap() because this leaves the page in > > limbo since it is not given back to the shrinker and also binder can't > > make use of it anymore. I'll send out a patch to fix this. > > Ok. Should that block this series or it will apply over it? The issue is pre-exiting and unrelated to this series. So I'll take care of this separately. Thanks!