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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10C31C43381 for ; Wed, 20 Mar 2019 19:57:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9ADA21841 for ; Wed, 20 Mar 2019 19:57:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726647AbfCTT5v (ORCPT ); Wed, 20 Mar 2019 15:57:51 -0400 Received: from gateway36.websitewelcome.com ([192.185.195.25]:40209 "EHLO gateway36.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726438AbfCTT5v (ORCPT ); Wed, 20 Mar 2019 15:57:51 -0400 X-Greylist: delayed 1460 seconds by postgrey-1.27 at vger.kernel.org; Wed, 20 Mar 2019 15:57:50 EDT Received: from cm16.websitewelcome.com (cm16.websitewelcome.com [100.42.49.19]) by gateway36.websitewelcome.com (Postfix) with ESMTP id 0D93840152F02 for ; Wed, 20 Mar 2019 13:49:48 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 6gxuhtUwu4FKp6gxuh79Yz; Wed, 20 Mar 2019 14:33:30 -0500 X-Authority-Reason: nr=8 Received: from [189.250.104.39] (port=59762 helo=[192.168.1.76]) by gator4166.hostgator.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.91) (envelope-from ) id 1h6gxt-003P2L-Dm; Wed, 20 Mar 2019 14:33:29 -0500 Subject: Re: [PATCH] PCI: Mark expected switch fall-throughs To: Bjorn Helgaas Cc: Boris Ostrovsky , Juergen Gross , Stefano Stabellini , Konrad Rzeszutek Wilk , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, Kees Cook References: <20190320182715.GA9406@embeddedor> <20190320192454.GB251185@google.com> From: "Gustavo A. R. Silva" Openpgp: preference=signencrypt Autocrypt: addr=gustavo@embeddedor.com; keydata= mQINBFssHAwBEADIy3ZoPq3z5UpsUknd2v+IQud4TMJnJLTeXgTf4biSDSrXn73JQgsISBwG 2Pm4wnOyEgYUyJd5tRWcIbsURAgei918mck3tugT7AQiTUN3/5aAzqe/4ApDUC+uWNkpNnSV tjOx1hBpla0ifywy4bvFobwSh5/I3qohxDx+c1obd8Bp/B/iaOtnq0inli/8rlvKO9hp6Z4e DXL3PlD0QsLSc27AkwzLEc/D3ZaqBq7ItvT9Pyg0z3Q+2dtLF00f9+663HVC2EUgP25J3xDd 496SIeYDTkEgbJ7WYR0HYm9uirSET3lDqOVh1xPqoy+U9zTtuA9NQHVGk+hPcoazSqEtLGBk YE2mm2wzX5q2uoyptseSNceJ+HE9L+z1KlWW63HhddgtRGhbP8pj42bKaUSrrfDUsicfeJf6 m1iJRu0SXYVlMruGUB1PvZQ3O7TsVfAGCv85pFipdgk8KQnlRFkYhUjLft0u7CL1rDGZWDDr NaNj54q2CX9zuSxBn9XDXvGKyzKEZ4NY1Jfw+TAMPCp4buawuOsjONi2X0DfivFY+ZsjAIcx qQMglPtKk/wBs7q2lvJ+pHpgvLhLZyGqzAvKM1sVtRJ5j+ARKA0w4pYs5a5ufqcfT7dN6TBk LXZeD9xlVic93Ju08JSUx2ozlcfxq+BVNyA+dtv7elXUZ2DrYwARAQABtCxHdXN0YXZvIEEu IFIuIFNpbHZhIDxndXN0YXZvQGVtYmVkZGVkb3IuY29tPokCPQQTAQgAJwUCWywcDAIbIwUJ CWYBgAULCQgHAgYVCAkKCwIEFgIDAQIeAQIXgAAKCRBHBbTLRwbbMZ6tEACk0hmmZ2FWL1Xi l/bPqDGFhzzexrdkXSfTTZjBV3a+4hIOe+jl6Rci/CvRicNW4H9yJHKBrqwwWm9fvKqOBAg9 obq753jydVmLwlXO7xjcfyfcMWyx9QdYLERTeQfDAfRqxir3xMeOiZwgQ6dzX3JjOXs6jHBP cgry90aWbaMpQRRhaAKeAS14EEe9TSIly5JepaHoVdASuxklvOC0VB0OwNblVSR2S5i5hSsh ewbOJtwSlonsYEj4EW1noQNSxnN/vKuvUNegMe+LTtnbbocFQ7dGMsT3kbYNIyIsp42B5eCu JXnyKLih7rSGBtPgJ540CjoPBkw2mCfhj2p5fElRJn1tcX2McsjzLFY5jK9RYFDavez5w3lx JFgFkla6sQHcrxH62gTkb9sUtNfXKucAfjjCMJ0iuQIHRbMYCa9v2YEymc0k0RvYr43GkA3N PJYd/vf9vU7VtZXaY4a/dz1d9dwIpyQARFQpSyvt++R74S78eY/+lX8wEznQdmRQ27kq7BJS R20KI/8knhUNUJR3epJu2YFT/JwHbRYC4BoIqWl+uNvDf+lUlI/D1wP+lCBSGr2LTkQRoU8U 64iK28BmjJh2K3WHmInC1hbUucWT7Swz/+6+FCuHzap/cjuzRN04Z3Fdj084oeUNpP6+b9yW e5YnLxF8ctRAp7K4yVlvA7kCDQRbLBwMARAAsHCE31Ffrm6uig1BQplxMV8WnRBiZqbbsVJB H1AAh8tq2ULl7udfQo1bsPLGGQboJSVN9rckQQNahvHAIK8ZGfU4Qj8+CER+fYPp/MDZj+t0 DbnWSOrG7z9HIZo6PR9z4JZza3Hn/35jFggaqBtuydHwwBANZ7A6DVY+W0COEU4of7CAahQo 5NwYiwS0lGisLTqks5R0Vh+QpvDVfuaF6I8LUgQR/cSgLkR//V1uCEQYzhsoiJ3zc1HSRyOP otJTApqGBq80X0aCVj1LOiOF4rrdvQnj6iIlXQssdb+WhSYHeuJj1wD0ZlC7ds5zovXh+FfF l5qH5RFY/qVn3mNIVxeO987WSF0jh+T5ZlvUNdhedGndRmwFTxq2Li6GNMaolgnpO/CPcFpD jKxY/HBUSmaE9rNdAa1fCd4RsKLlhXda+IWpJZMHlmIKY8dlUybP+2qDzP2lY7kdFgPZRU+e zS/pzC/YTzAvCWM3tDgwoSl17vnZCr8wn2/1rKkcLvTDgiJLPCevqpTb6KFtZosQ02EGMuHQ I6Zk91jbx96nrdsSdBLGH3hbvLvjZm3C+fNlVb9uvWbdznObqcJxSH3SGOZ7kCHuVmXUcqoz ol6ioMHMb+InrHPP16aVDTBTPEGwgxXI38f7SUEn+NpbizWdLNz2hc907DvoPm6HEGCanpcA EQEAAYkCJQQYAQgADwUCWywcDAIbDAUJCWYBgAAKCRBHBbTLRwbbMdsZEACUjmsJx2CAY+QS UMebQRFjKavwXB/xE7fTt2ahuhHT8qQ/lWuRQedg4baInw9nhoPE+VenOzhGeGlsJ0Ys52sd XvUjUocKgUQq6ekOHbcw919nO5L9J2ejMf/VC/quN3r3xijgRtmuuwZjmmi8ct24TpGeoBK4 WrZGh/1hAYw4ieARvKvgjXRstcEqM5thUNkOOIheud/VpY+48QcccPKbngy//zNJWKbRbeVn imua0OpqRXhCrEVm/xomeOvl1WK1BVO7z8DjSdEBGzbV76sPDJb/fw+y+VWrkEiddD/9CSfg fBNOb1p1jVnT2mFgGneIWbU0zdDGhleI9UoQTr0e0b/7TU+Jo6TqwosP9nbk5hXw6uR5k5PF 8ieyHVq3qatJ9K1jPkBr8YWtI5uNwJJjTKIA1jHlj8McROroxMdI6qZ/wZ1ImuylpJuJwCDC ORYf5kW61fcrHEDlIvGc371OOvw6ejF8ksX5+L2zwh43l/pKkSVGFpxtMV6d6J3eqwTafL86 YJWH93PN+ZUh6i6Rd2U/i8jH5WvzR57UeWxE4P8bQc0hNGrUsHQH6bpHV2lbuhDdqo+cM9eh GZEO3+gCDFmKrjspZjkJbB5Gadzvts5fcWGOXEvuT8uQSvl+vEL0g6vczsyPBtqoBLa9SNrS VtSixD1uOgytAP7RWS474w== Message-ID: Date: Wed, 20 Mar 2019 14:33:27 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: <20190320192454.GB251185@google.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.250.104.39 X-Source-L: No X-Exim-ID: 1h6gxt-003P2L-Dm X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: ([192.168.1.76]) [189.250.104.39]:59762 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 14 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On 3/20/19 2:24 PM, Bjorn Helgaas wrote: > On Wed, Mar 20, 2019 at 01:27:15PM -0500, Gustavo A. R. Silva wrote: >> In preparation to enabling -Wimplicit-fallthrough, mark switch >> cases where we are expecting to fall through. > > Does this fix all the remaining cases in drivers/pci? I'd like to fix > them all at once. > These are actually the last ones. > What's the best way to watch for new warnings being added? I fiddled > with "make W=2" etc but it didn't seem useful. Does the 0-day robot > warn when -Wimplicit-fallthrough warnings are added? > 0-day robot doesn't know about these warnings yet. But it certainly will once we finally enable -Wimplicit-fallthrough. Add this to your Makefile to see the warnings: KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough=3,) Thanks -- Gustavo > Bjorn > >> This patch fixes the following warnings: >> >> drivers/pci/proc.c: In function ‘proc_bus_pci_ioctl’: >> drivers/pci/proc.c:216:6: warning: this statement may fall through [-Wimplicit-fallthrough=] >> if (arch_can_pci_mmap_wc()) { >> ^ >> drivers/pci/proc.c:225:2: note: here >> default: >> ^~~~~~~ >> >> drivers/pci/xen-pcifront.c: In function ‘pcifront_backend_changed’: >> drivers/pci/xen-pcifront.c:1105:6: warning: this statement may fall through [-Wimplicit-fallthrough=] >> if (xdev->state == XenbusStateClosed) >> ^ >> drivers/pci/xen-pcifront.c:1108:2: note: here >> case XenbusStateClosing: >> ^~~~ >> >> Notice that, in this particular case, the /* fall through */ >> comment is placed at the very bottom of the case statement, >> which is what GCC is expecting to find. >> >> Warning level 3 was used: -Wimplicit-fallthrough=3 >> >> This patch is part of the ongoing efforts to enable >> -Wimplicit-fallthrough. >> >> Signed-off-by: Gustavo A. R. Silva >> --- >> drivers/pci/proc.c | 1 + >> drivers/pci/xen-pcifront.c | 2 +- >> 2 files changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c >> index 6fa1627ce08d..445b51db75b0 100644 >> --- a/drivers/pci/proc.c >> +++ b/drivers/pci/proc.c >> @@ -222,6 +222,7 @@ static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd, >> } >> /* If arch decided it can't, fall through... */ >> #endif /* HAVE_PCI_MMAP */ >> + /* fall through */ >> default: >> ret = -EINVAL; >> break; >> diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c >> index eba6e33147a2..14cf0f41ecf0 100644 >> --- a/drivers/pci/xen-pcifront.c >> +++ b/drivers/pci/xen-pcifront.c >> @@ -1104,7 +1104,7 @@ static void __ref pcifront_backend_changed(struct xenbus_device *xdev, >> case XenbusStateClosed: >> if (xdev->state == XenbusStateClosed) >> break; >> - /* Missed the backend's CLOSING state -- fallthrough */ >> + /* fall through - Missed the backend's CLOSING state. */ >> case XenbusStateClosing: >> dev_warn(&xdev->dev, "backend going away!\n"); >> pcifront_try_disconnect(pdev); >> -- >> 2.21.0 >>