From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 18FE2306B05 for ; Mon, 30 Mar 2026 06:20:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774851645; cv=none; b=Mo6WXbP73gpglL73nBHFSF4JnBQiOxkdv2/0S7TRtm+XZy7Ipg87mNh0a0n4BiDp7WoKqUOaEryFOFCifcuS9TxaRMk/Eag+zBkDH+4xVkGFCGdgZS1305i8u6GQrEMXoCigMRw2sxxQjGaw8JipuRSY2OFq7wWKKd0TT4zHYSA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774851645; c=relaxed/simple; bh=nFxy5rksdx//ssg9glpOenDGjIYz5fHubduPfHs7ma4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hweNSWGSS2bk/BcIrKwvLh9fhlZIRjdz43wSqHd0h82S5VrWlzvOk/4XhY7aZ6x2TS4Eexf4vioMfzf7kBMIPzSjE8u9di7MqxzluPY8vugHqG7s8naTRlSLk+Tcs1VA5l1Ux2Q9Kd6RPdB1ogv1d3FKWd6WUqQ2jDa5mKvFRjc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=ypJ2K2n3; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ypJ2K2n3" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Transfer-Encoding :Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=ETQSKJTY66rZCvnD09d1z8wM5Mh9Wrtt3bPMhswqLLQ=; b=ypJ2K2n3gJJ19uGuH2CbJAT/b8 1JVHZnv7DUznFgXYh7gro1fCYy2FPkhP8RWu+E407xZywIkSd5BI3nWgvL6uxYwBdPPrUvz0wklm8 jcZw4rbLeE/F92oOHi+Ns+rwwVuG65Eo84U6zsHHOq7piFjzi14sP+FI6/fugkri/J2JAWToB8kjp IFkV1jGigYLnb4lNvL0yJAQZAdqgp14cxlIZXGRQvZDoH82zzzRNTBxpxfuAIPBdG0+VSRghmrmyw Jv1G9XXWoluT+uYJ4Unt/WpCItYeIAM2+Rom/Ndp0vreVhixLkkhAsVA05t3rkPJJvQC5T1RTmkGK 5Q4eHRuQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1w75zO-0000000Ag3t-3nza; Mon, 30 Mar 2026 06:20:42 +0000 Date: Sun, 29 Mar 2026 23:20:42 -0700 From: Christoph Hellwig To: mpenttil@redhat.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Subject: Re: [PATCH v7 1/6] mm:/Kconfig changes for migrate on fault for device pages Message-ID: References: <20260330043017.251808-1-mpenttil@redhat.com> <20260330043017.251808-2-mpenttil@redhat.com> 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=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260330043017.251808-2-mpenttil@redhat.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Mon, Mar 30, 2026 at 07:30:12AM +0300, mpenttil@redhat.com wrote: > From: Mika Penttilä > > With the unified HMM/migrate_device page table walk > migrate_device needs HMM enabled and HMM needs > MMU notifiers. Enable them explicitly to avoid > breaking random configs. You can use a lot more space in your commit logs, ending the lines so early reads a bit weird. > diff --git a/mm/Kconfig b/mm/Kconfig > index ebd8ea353687..583d92bba2e8 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -647,6 +647,7 @@ config MIGRATION > > config DEVICE_MIGRATION > def_bool MIGRATION && ZONE_DEVICE > + select HMM_MIRROR > > config ARCH_ENABLE_HUGEPAGE_MIGRATION > bool > @@ -1222,6 +1223,7 @@ config ZONE_DEVICE > config HMM_MIRROR > bool > depends on MMU > + select MMU_NOTIFIER But either way this really should go into the patch that actually adds the code dependency anyway.