From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932259AbcHZPe6 (ORCPT ); Fri, 26 Aug 2016 11:34:58 -0400 Received: from mout.kundenserver.de ([212.227.126.130]:57996 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932193AbcHZPe4 (ORCPT ); Fri, 26 Aug 2016 11:34:56 -0400 From: Arnd Bergmann To: linux-kernel@vger.kernel.org Cc: Linus Torvalds , Arnd Bergmann , Alexandre Courbot , David Howells , "David S. Miller" , Fushen Chen , Hadar Hen Zion , Iyappan Subramanian , Jiri Pirko , Keyur Chudgar , Linus Walleij , Phil Reid , Russell King , Tomi Valkeinen , linux-fbdev@vger.kernel.org, linux-gpio@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH 0/5] -Wmaybe-uninitialized bug fixes for linux-next Date: Fri, 26 Aug 2016 17:25:41 +0200 Message-Id: <20160826152546.604384-1-arnd@arndb.de> X-Mailer: git-send-email 2.9.0 X-Provags-ID: V03:K0:bRw+H5hc/mKrcs3J776WszZ7fa2rpj+eGSh0Mip6wD5pJMcdw6A IqfbLmGuY6/0RYZ+03fmfJv9PUvo3ykkLZDHC0xQa5Og9TFPkszhq8yjm3fdIaFH+0Xgmvo f857g0KQ1xfF27p/Lld6gi7fLt3V7cfQZu8cEOoxHRQers8uCbuzPpqnetoFla5im73NlOp bDlMJkZGj3FNNq/I0SY3w== X-UI-Out-Filterresults: notjunk:1;V01:K0:x0H94d++mvs=:6QLaK2cSeXXzKNr2z36a0+ 2USLw78kCdwJCIoVKFcREd/7IVatRXGbvGlxyPcwSuegkEsV/BobgHFeqWjN2aIrXxWPMU8DT A0JpNR32H1XgB+sEfaGxppnoR9t3VABmUUHWvCuKqb/Jtyl91K4P2XsZEzSxueiCc6Q0BtbPF Svh8pmAn+XstQo5plYBIwl6jwQFTEXi8tS7Fkgqasoz3SZa4clowaAlsuAX2Y7VfVrt9xrm57 gWtwff1PucE5IHlcMHFx6GRyCjIFvszPR2cGseQtcABR5d1gKHo47gaXQfAEsH6u4XwMx10/L qHx13wLVUryaDeQfZkGMWQ/wlY0mHZbvLvDijtDBhb/qmihxupkKYWUJAumlXpiEWojDrbU6X P8fWGa74+CEfZHAAolzgrh4jhEvgl0cmgvHWNx58xtESEmuN8R2bAcJPjb9ZTwwVx9eo/VvrB XZOGLETPSOGYTcSUPOfiyDsqH8JX+pVNKMZl0KDdMH1HPnwNzbf/wIpvgme6Fzg3Q2WKCvl0L pQVDzQS/5HTGaPIE4NPgQ7hruQjqBVR4W650I+/yDq07O6ihvSKcJS9G2uRlwE7kgN+zPWIZO KQ3rgDtj+IXAn2HshXsvdsbjWpFT3jnspCWrTsJ1aI9NRzYLzDyYv6gPcxhDwlsjBDkwcynYv vRzE2Mho4By1Na3Vcaj4//hbFN6oYWt8dWj3mQ/9WcJScNnsSxOxy++/f5lNPspFalrk= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In 6e8d666e9253 ("Disable "maybe-uninitialized" warning globally"), Linus wrote: Looking at the warnings produced, every single one I looked at was a false positive, and the warnings are frequent enough (and big enough) that they can easily hide real problems that you don't notice in the noise generated by -Wmaybe-uninitialized. Today, I tried reverting the patch on linux-next and built an ARM allmodconfig kernel on ARM along with some randconfig kernels, and got a handful of warnings, all of which appear to be reasonable and point to actual mistakes in the code. The difference to what Linus saw must be that previously the useful warnings were more likely to get fixed before making it into the kernel, while now we have to find them the hard way. These five patches address all new warnings. In some cases this may not be the correct fix, so please review carefully before applying, or suggest a better fix. No need to keep them as a series, I just group them here for the sake of discussion. Please pick up whatever looks right to you. Obviously, this kind of warnings always produces some false positives (see https://gcc.gnu.org/wiki/Better_Uninitialized_Warnings), but I still hope to get a better balance with enabling them sometimes where people want them, as the current approach of always enabling them for "make W=1" but never by default seems suboptimal: We had previously identified a number of options (CONFIG_CC_OPTIMIZE_FOR_SIZE, CONFIG_PROFILE_ALL_BRANCHES, CONFIG_UBSAN_ALIGNMENT, and CONFIG_GCOV_PROFILE_ALL) that cause tons of false positives, but without those options (and avoiding gcc-4.8 or lower), we typically get mostly reports for actual bugs in my experience. I can continue running the tests and send patches, but it feels like a waste of time when they should have been found by the original developers. Any other suggestions? Arnd Arnd Bergmann (5): gpio: pca954x: fix undefined error code from remove video: ARM CLCD: fix endpoint lookup logic rxrpc: fix last_call processing net_sched: fix use of uninitialized ethertype variable in cls_flower net/xgene: fix error handling during reset drivers/gpio/gpio-pca953x.c | 2 ++ drivers/net/ethernet/apm/xgene/xgene_enet_xgmac.c | 12 +++++++++--- drivers/video/fbdev/amba-clcd.c | 9 +++------ net/rxrpc/input.c | 8 ++++---- net/sched/cls_flower.c | 21 +++++++++++---------- 5 files changed, 29 insertions(+), 23 deletions(-) Cc: Alexandre Courbot Cc: David Howells Cc: "David S. Miller" Cc: Fushen Chen Cc: Hadar Hen Zion Cc: Iyappan Subramanian Cc: Jiri Pirko Cc: Keyur Chudgar Cc: Linus Walleij Cc: Phil Reid Cc: Russell King Cc: Tomi Valkeinen Cc: linux-fbdev@vger.kernel.org Cc: linux-gpio@vger.kernel.org Cc: netdev@vger.kernel.org -- 2.9.0