From patchwork Tue Sep 18 22:15:00 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Alex G." X-Patchwork-Id: 971321 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="VJcGAdGU"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42FHNw69Z4z9s9h for ; Wed, 19 Sep 2018 08:15:12 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728280AbeISDtv (ORCPT ); Tue, 18 Sep 2018 23:49:51 -0400 Received: from mail-ot1-f66.google.com ([209.85.210.66]:43408 "EHLO mail-ot1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728266AbeISDtv (ORCPT ); Tue, 18 Sep 2018 23:49:51 -0400 Received: by mail-ot1-f66.google.com with SMTP id u20-v6so3653200otk.10; Tue, 18 Sep 2018 15:15:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=rXvV8fXs2990Ulo3FcjusvBfvCLnVtKwk4vA/rqOC6o=; b=VJcGAdGUpobvwwBHFNpFkcMMkD2QpI94qPmUBxe4wbfaY46s19/BUCHJMbIN9xEAdF HXoZ0H8AUbLU3BlvcMSx/2XBF6iZyee7Fg133cVrmRjhhpmIB9XCpBgQvHfab7hWhmeM d0qLWrO471t0TnIC8xJ6zqRomza3j7V4UgGc158tdV6edsrnb2H5uXusay3RZxD3upcp SZnMBKeZD6eD3w4uAiNyZtf5SL49NXD1LytRxcXTec/6o4c5ybI/kupVQi/LjxnXBx/G XgxEibnyXktZauFvxSmtR0dQPSZVbGGSEac35wZG7lRKdRbLNeEJJ/mmEMfwPFhml7+P 1OUw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=rXvV8fXs2990Ulo3FcjusvBfvCLnVtKwk4vA/rqOC6o=; b=crVl3PJSHv13bTv8ntLUSRRrpDDrjIw6jaqtYK+J8qDsQbyziC+Kkig4VZzoe+Uz1m htZ6kMow5d6sbFJCkK8g9emd0MFKD5KE3U3L9SgEQ1wcl/LjIW+TnC4aAaEGrIW6VoDm Zj22Y0dtl+AQq7KnWIlp8KQx9jDWg/2QhlkiHyA/J2+ZTxTSdZkD8Jo9BgGQCjigimH1 eX/sWIzNYATOJnRFYFWGuW7C6LPOS04y82IZHjMwtZrLPlhZ/husOJUqny2x+WR/CDiO 0JUusA6ty6R7MMjg3DwltJeCojKVO2uWkK6vrCLTmwtgOhT1FTIdg3GDJDBtx3efa0eZ whzg== X-Gm-Message-State: APzg51DtPCV/upzJXErzsrxYNuEio7+EhgForA4QXBJF1bIPpHdum8VU esxY2HInT7sKXWaONNrlMfcp9YKl X-Google-Smtp-Source: ANB0VdacNUSlIXqjmUpYgfdDUtctWCKEmtYI13iBvEY0j7xZ0cRoDxhZ1yInMGl36k0+cTNNE/WROw== X-Received: by 2002:a9d:2a50:: with SMTP id t74-v6mr18175193ota.234.1537308910612; Tue, 18 Sep 2018 15:15:10 -0700 (PDT) Received: from nuclearis2-1.lan (c-98-195-139-126.hsd1.tx.comcast.net. [98.195.139.126]) by smtp.gmail.com with ESMTPSA id r18-v6sm6136732otc.24.2018.09.18.15.15.09 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 18 Sep 2018 15:15:09 -0700 (PDT) From: Alexandru Gagniuc To: linux-pci@vger.kernel.org, bhelgaas@google.com Cc: keith.busch@intel.com, alex_gagniuc@dellteam.com, austin_bolen@dell.com, shyam_iyer@dell.com, Alexandru Gagniuc , linux-kernel@vger.kernel.org Subject: [PATCH v2] PCI/MSI: Don't touch MSI bits when the PCI device is disconnected Date: Tue, 18 Sep 2018 17:15:00 -0500 Message-Id: <20180918221501.13112-1-mr.nuke.me@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org When a PCI device is gone, we don't want to send IO to it if we can avoid it. We expose functionality via the irq_chip structure. As users of that structure may not know about the underlying PCI device, it's our responsibility to guard against removed devices. .irq_write_msi_msg() is already guarded inside __pci_write_msi_msg(). .irq_mask/unmask() are not. Guard them for completeness. For example, surprise removal of a PCIe device triggers teardown. This touches the irq_chips ops some point to disable the interrupts. I/O generated here can crash the system on firmware-first machines. Not triggering the IO in the first place greatly reduces the possibility of the problem occurring. Signed-off-by: Alexandru Gagniuc Tested-by: Jon Derrick --- drivers/pci/msi.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index f2ef896464b3..f31058fd2260 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -227,6 +227,9 @@ static void msi_set_mask_bit(struct irq_data *data, u32 flag) { struct msi_desc *desc = irq_data_get_msi_desc(data); + if (pci_dev_is_disconnected(msi_desc_to_pci_dev(desc))) + return; + if (desc->msi_attrib.is_msix) { msix_mask_irq(desc, flag); readl(desc->mask_base); /* Flush write to device */