From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 297EA2C85 for ; Thu, 4 Nov 2021 12:32:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=iQDesZV5L2mroTI3Kp4Q9Tkxn1uaR3bTz2ke0CiK9wE=; b=l05sE+7qLWw6hasWyI/n0sgCrx 1gk2a/tDTo4hfhxCY2tx9KEeS3Me3gh5TO/MYJsvwrTQ7Uk2XzOQGVGEMRKLI0tl9ouAAsajZAYQQ qScYChjvl1Mx+k3w3OHPSsjy5wz1TeQFTAVbPl7mJTLC5cHnGIhKhN5wdbQ3QGtSMGeCl+zqA7hp2 NUJ72xXrPItCUBAWEQGuvyeMknqkRWwyQVRjCFS2B/hFsjoTkXs0Y5uFTY1Z1L03Sl+V6x8ko9F25 HEy9RYwqNe19PXKLzMA3IoGWaMQYYlH6x+koORZ53RoCD2TIuFZVTG2orIoah0SlzuiAe3oRIVf0i 7wQ3cDPA==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mibrf-005rYi-P5; Thu, 04 Nov 2021 12:29:31 +0000 Date: Thu, 4 Nov 2021 12:29:07 +0000 From: Matthew Wilcox To: Christoph Hellwig Cc: Dan Williams , "Darrick J. Wong" , Jane Chu , "david@fromorbit.com" , "vishal.l.verma@intel.com" , "dave.jiang@intel.com" , "agk@redhat.com" , "snitzer@redhat.com" , "dm-devel@redhat.com" , "ira.weiny@intel.com" , "vgoyal@redhat.com" , "linux-fsdevel@vger.kernel.org" , "nvdimm@lists.linux.dev" , "linux-kernel@vger.kernel.org" , "linux-xfs@vger.kernel.org" Subject: Re: [dm-devel] [PATCH 0/6] dax poison recovery with RWF_RECOVERY_DATA flag Message-ID: References: <2102a2e6-c543-2557-28a2-8b0bdc470855@oracle.com> <20211028002451.GB2237511@magnolia> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Nov 04, 2021 at 01:30:48AM -0700, Christoph Hellwig wrote: > Well, the whole problem is that we should not have to manage this at > all, and this is where I blame Intel. There is no good reason to not > slightly overprovision the nvdimms and just do internal bad page > remapping like every other modern storage device. What makes you think they don't? The problem is persuading the CPU to do writes without doing reads. That's where magic instructions or out of band IO is needed.