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 51FFD1B3B33 for ; Wed, 21 Aug 2024 11:44:05 +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=1724240652; cv=none; b=nHYPrx2ohnmaUmjtLBsUv2j8axMxyYYXZBQsCqrwuU5W9r1Kn6XsGGhDlmNe9hIruuTh00IsUKVDxTcpC9ti3bQAz6uboiuh/8d1ztYgOIjfzmqnsykcQ0LrxO6YOYxsuY7y52zgXgHk9v2A6Gw4TLzPoi91/oQ3N+5vNitEX8E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724240652; c=relaxed/simple; bh=loir6ub4Jgl9EL63HTjD5sof3Gk9J8WuwpAwu6fgMY8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uk5vySOqc2aiwwCxTVPdqkILtwfB/sNfmb2LBlpPUfIlYFaMstDBiCTKT50u1kcw6xuQpxNFuXQb0qIC1xTZYlXIVgjRbCU8gOa4VgxTnKng9e3Eh6UmOyPJnItYL9Fdm4gSP2g9rjjL7LO2ERv5yt9aZKpsMh+AaSwoOzEmZUU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (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=soGsd5Za; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (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="soGsd5Za" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=G1NccRhi7/UxbXUXfvO5IP+/hVG27t4u56SnhsRtCy0=; b=soGsd5ZaLfm9FSjnB5aMi6/WkQ pmMFWUo3lKcBJ32X09BwZxVo3CgANfs7wcJpX76m/O/zeG/UzM/QmZ9O2L0pKtzpApQhjbdDkF/8v GafDVUCF78szYZKI+TX/4hoXcqy5fNWPP+wopOIJrgxzwiNwzD+YbtsliXgKyh74hz64EasnV5KHU KI0xi0d29eYXuO+jpRSr5viNXLoDLU/PnUpl0H1lZdUvSV/L/EhWO1yJOM531hSyaG8PgPJO9Sww4 g0NAdYLOziuKOMFUZrBEz835bEbVZJEd875YLK9kw/h0/5mpNydLyWs4V5hDK0EVHsw8O5bnaf/lK 7i5rQnoA==; Received: from hch by bombadil.infradead.org with local (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgjkx-00000008kj6-1UZH; Wed, 21 Aug 2024 11:44:03 +0000 Date: Wed, 21 Aug 2024 04:44:03 -0700 From: Christoph Hellwig To: Michal Hocko Cc: Christoph Hellwig , Yafang Shao , Andrew Morton , viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, david@fromorbit.com, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Kent Overstreet Subject: Re: [PATCH] mm: document risk of PF_MEMALLOC_NORECLAIM Message-ID: References: Precedence: bulk X-Mailing-List: linux-fsdevel@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: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Fri, Aug 16, 2024 at 10:54:37AM +0200, Michal Hocko wrote: > Yes, I think we should kill it before it spreads even more but I would > not like to make the existing user just broken. I have zero visibility > and understanding of the bcachefs code but from a quick look at __bch2_new_inode > it shouldn't be really terribly hard to push GFP_NOWAIT flag there > directly. > I don't understand that sentence. You're adding the gfp_t argument to it, which to mean counts as pushing it there directly. > It would require inode_init_always_gfp variant as well (to not > touch all existing callers that do not have any locking requirements but > I do not see any other nested allocations. inode_init_always only has 4 callers, so I'd just add the gfp_t argument. Otherwise this looks good modulo the fix your posted: Acked-by: Christoph Hellwig