From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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.lore.kernel.org (Postfix) with ESMTPS id 2F531C433EF for ; Mon, 6 Jun 2022 06:51:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hWQ11zN6+QeYeDbRx/qX9fS1bgedji/36Ds1YPi6WVk=; b=htgATZpTtxbugIEGLXJW1QVV0v tl2iuJKBfiysCX5ok67wO/DX3gpVMhjz/bGJhjPVKur/D40txfOh/2Um+pXUgkn/bR660hWfOIXnv RgTfT99zstNletJFTyX90K2IKf8SJOY2WgDGVOA1Szd1SJOvBFZsQ9WVzHUmd+e8Wj9EoIFH768j9 G/jgOcyJPhay09D4g96p73OAdeBodT9nGY/syZS/bEF81LGO/QhKzvnb6alLXrVgx9b47MXkXaWG2 uhOKihYbQMnKihhvPy2ZogJCEAv+Ma1a0Ix96hj0EH/G3pnROfMk25WgHiuaoGtDWsHnj8SMa+nbv ffshfTxQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ny6aK-00HR9V-Gv; Mon, 06 Jun 2022 06:51:32 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ny6Zv-00HQxe-Ag for linux-nvme@lists.infradead.org; Mon, 06 Jun 2022 06:51:08 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 6555868AA6; Mon, 6 Jun 2022 08:51:03 +0200 (CEST) Date: Mon, 6 Jun 2022 08:51:02 +0200 From: "hch@lst.de" To: "Michael Kelley (LINUX)" Cc: Keith Busch , "axboe@fb.com" , "hch@lst.de" , "sagi@grimberg.me" , "linux-nvme@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Caroline Subramoney , Richard Wurdack , Nathan Obr Subject: Re: [PATCH v2 2/2] nvme: handle persistent internal error AER from NVMe controller Message-ID: <20220606065102.GA2551@lst.de> References: <1654278961-81423-1-git-send-email-mikelley@microsoft.com> <1654278961-81423-2-git-send-email-mikelley@microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220605_235107_561987_7931F844 X-CRM114-Status: GOOD ( 17.20 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Sat, Jun 04, 2022 at 02:28:11PM +0000, Michael Kelley (LINUX) wrote: > > driver's irq handler. The other transports block on register reads, though, so > > they can't call this from an atomic context. The TCP context looks safe, but > > I'm not sure about RDMA or FC. > > Good point. But even if the RDMA and FC contexts are safe, For RDMA this is typically called from softirq context, so it is indeed not save. > if a > persistent error is reported, the controller is already in trouble and > may not respond to a request to retrieve the CSTS anyway. Perhaps > we should just trust the AER error report and not bother checking > CSTS to decide whether to do the reset. We can still check ctrl->state > and skip the reset if there's already one in progress. Yes, that might be a better option.