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 3EE85376A12 for ; Thu, 11 Jun 2026 08:01:55 +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=1781164916; cv=none; b=MwaM/AU7VveKEoOCVk8uq4VA77+g91shN6Z8XKPyuAc0k3fpMuoY9S+3M+6NpIYY/3GYOiKP7QIMHFKa50Tn7LiXiCOQyd78Atp5YE6bVl6ZogjRg3YUBhYmB+X09xnds+T/q7K6gHycP8ikm9RQJpRtKQhJsabWp+2tMJVQb50= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781164916; c=relaxed/simple; bh=dParKWFz+zW5THjdPs8fKKQoIa6skaTn2+v8jhOS+0c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pGvbRtJgzDssXLTZOP+I9zQOVN6/E8ZgdOZTISOm6T0tNKMV4nhpUqb48xYinTdfXjTbs3KqrmIbyFYSzLDTUa6Fd3efd35I/5pWDD0+JdpGYHWvrxGkdrMxCo1bNBmZQ3iM/qDwRGmkfMC+oIM1QLy9qNzWmJ3hkrcGVPHqEyo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bsbYHwWC; 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="bsbYHwWC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CCDE81F00893; Thu, 11 Jun 2026 08:01:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781164915; bh=7dD4/CQnNeeyrkkOYOUO1mj3STEaisPLiFqjfCgk+JU=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=bsbYHwWCImv67tbIFfumvMYPTQMPVJc9B3XM2fOGxPEjlnUB+K4WQ9QG3o2NQgESI S3mJJCx7sB4kxjBR8Xq6WeTFztqOZ5pKDfXAZ2XC/oxUNFL9s/ORvUGAsDY0Po1wSL hi98GUJnxp2ohZBQvHHfc91d9R+dcHsCwXHangO9vzQQiORIWO38cO2ZXpLTFiSmzz eqqdP2AAWx77dUNV3PXKsTNuZLpJueU3U9f+kYMngrNOvDfdvVqy8Nam2hlKwzK06r gXdGzGy2Cp6eZudu8zMb2EALFYVG1jEjIJ8qHdYpT9AqcjbKw1aPFg947/4XnfjPZT QFBWEtJ+B4WJw== Date: Thu, 11 Jun 2026 10:01:47 +0200 From: "Oscar Salvador (SUSE)" To: Lorenzo Stoakes Cc: Andrew Morton , Arnd Bergmann , Greg Kroah-Hartman , David Hildenbrand , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Pedro Falcato , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v3 3/3] mm/vma: eliminate mmap_action->error_hook, introduce error_override Message-ID: References: <55d13f7d016b827c459946d46a56105635be111c.1780397980.git.ljs@kernel.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=us-ascii Content-Disposition: inline In-Reply-To: <55d13f7d016b827c459946d46a56105635be111c.1780397980.git.ljs@kernel.org> On Tue, Jun 02, 2026 at 12:06:27PM +0100, Lorenzo Stoakes wrote: > Rather than providing a hook, simplify things by providing the ability to > override mmap action errors. This allows us to more carefully validate the > value provided and thus ensure only a valid error code is specified, and > simplifies the interface. > > This way, we eliminate all hooks but mmap_prepare and allow only mmap > actions to be specified (which core mm controls). > > This significantly improves robustness and eliminates any unnecessary code > duplication in driver mmap hooks. > > We also update the /dev/mem logic (the only user) to use > mmap_action->error_override instead. > > Signed-off-by: Lorenzo Stoakes Reviewed-by: Oscar Salvador (SUSE) -- Oscar Salvador SUSE Labs