From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: linux-next: Tree for Jan 7 Date: Wed, 7 Jan 2015 10:09:22 -0800 Message-ID: <20150107180922.GC5280@linux.vnet.ibm.com> References: <20150107151618.7cb9d574@canb.auug.org.au> <20150107142656.GA5666@roeck-us.net> <20150107163310.GZ5280@linux.vnet.ibm.com> <20150107173022.GA26631@roeck-us.net> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from e35.co.us.ibm.com ([32.97.110.153]:34459 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753818AbbAGSJ3 (ORCPT ); Wed, 7 Jan 2015 13:09:29 -0500 Received: from /spool/local by e35.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 7 Jan 2015 11:09:28 -0700 Content-Disposition: inline In-Reply-To: <20150107173022.GA26631@roeck-us.net> Sender: linux-next-owner@vger.kernel.org List-ID: To: Guenter Roeck Cc: Stephen Rothwell , linux-next@vger.kernel.org, linux-kernel@vger.kernel.org, Christian Borntraeger , linux-sh@vger.kernel.org On Wed, Jan 07, 2015 at 09:30:22AM -0800, Guenter Roeck wrote: > On Wed, Jan 07, 2015 at 08:33:10AM -0800, Paul E. McKenney wrote: > > On Wed, Jan 07, 2015 at 06:26:56AM -0800, Guenter Roeck wrote: > > > On Wed, Jan 07, 2015 at 03:16:18PM +1100, Stephen Rothwell wrote: > > > > Hi all, > > > > > > > > Changes since 20150106: > > > > > > > > *crickets* > > > > > > > > Non-merge commits (relative to Linus' tree): 1350 > > > > 1543 files changed, 41856 insertions(+), 24250 deletions(-) > > > > > > > > ---------------------------------------------------------------------------- > > > > > > > > > > New build failure for sh:dreamcast_defconfig: > > > > > > arch/sh/mm/gup.c: In function 'gup_get_pte': > > > arch/sh/mm/gup.c:20:2: error: invalid initializer > > > make[1]: *** [arch/sh/mm/gup.o] Error 1 > > > > > > bisect log: > > > > > > # bad: [7e3619a6de57f0257a2f6480182d2287ee05e314] Add linux-next specific files for 20150107 > > > # good: [b1940cd21c0f4abdce101253e860feff547291b0] Linux 3.19-rc3 > > > git bisect start 'HEAD' 'v3.19-rc3' > > > # good: [c48667c5659248ff2b2fbff5cd23c43b5768e81b] Merge remote-tracking branch 'net-next/master' > > > git bisect good c48667c5659248ff2b2fbff5cd23c43b5768e81b > > > # good: [b8cf629ce7d554711dd7ab256b00e6110355e1d7] Merge remote-tracking branch 'mmc-uh/next' > > > git bisect good b8cf629ce7d554711dd7ab256b00e6110355e1d7 > > > # good: [cc52ff032bc2d91c78d7cf9aefcfa9e266ace816] Merge remote-tracking branch 'rcu/rcu/next' > > > git bisect good cc52ff032bc2d91c78d7cf9aefcfa9e266ace816 > > > # bad: [9634277bcdab7b9d6a91409dc11d85502aa2e74b] Merge remote-tracking branch 'access_once/linux-next' > > > git bisect bad 9634277bcdab7b9d6a91409dc11d85502aa2e74b > > > # good: [261379560ee6aa65b4869c94eda0d3d60773aca3] Merge remote-tracking branch 'scsi/for-next' > > > git bisect good 261379560ee6aa65b4869c94eda0d3d60773aca3 > > > # good: [38d45afa56bfca714780e45532760d64cd53b65b] Merge remote-tracking branch 'llvmlinux/for-next' > > > git bisect good 38d45afa56bfca714780e45532760d64cd53b65b > > > # good: [9afbe1ce2403c7d097bfaafcc5b27950040f7608] Merge remote-tracking branch 'y2038/y2038' > > > git bisect good 9afbe1ce2403c7d097bfaafcc5b27950040f7608 > > > # bad: [a91ed664749cbec0325ef9da7d12619d9bb72e2d] kernel: tighten rules for ACCESS ONCE > > > git bisect bad a91ed664749cbec0325ef9da7d12619d9bb72e2d > > > # good: [e3865cc4a17e979e6b2f26af026686fae5567096] x86/xen/p2m: Replace ACCESS_ONCE with READ_ONCE > > > git bisect good e3865cc4a17e979e6b2f26af026686fae5567096 > > > # good: [e2579c6f22ee0a43394d603cef6989dca98c5610] mm/gup: Replace ACCESS_ONCE with READ_ONCE > > > git bisect good e2579c6f22ee0a43394d603cef6989dca98c5610 > > > # first bad commit: [a91ed664749cbec0325ef9da7d12619d9bb72e2d] kernel: tighten rules for ACCESS ONCE > > > > > > Maybe the ACCESS_ONCE in the affected file should be replaced with READ_ONCE ? > > > > That is my belief. What happens when you try it? > > > Build passes, and my qemu tests pass as well. That doesn't mean > that the change is correct, of course, since I don't know if the code > in question is executed. Would it be possible to increment a counter at that location, then print it out at some convenient point? > Should I send a patch with the change ? I believe such a patch is needed. Testing would be good, but the patch is what we were thinking of for this situation. Thanx, Paul