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[142.68.80.239]) by smtp.gmail.com with ESMTPSA id bf10-20020a056830354a00b006e2f7ddf4eesm136171otb.28.2024.02.13.06.42.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Feb 2024 06:42:09 -0800 (PST) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1rZtz6-004WEV-5n; Tue, 13 Feb 2024 10:42:08 -0400 Date: Tue, 13 Feb 2024 10:42:08 -0400 From: Jason Gunthorpe To: Will Deacon Cc: Dmitry Baryshkov , Robin Murphy , Joerg Roedel , Rob Clark , linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH] Revert "iommu/arm-smmu: Convert to domain_alloc_paging()" Message-ID: <20240213144208.GL765010@ziepe.ca> References: <20240213-iommu-revert-domain-alloc-v1-1-325ff55dece4@linaro.org> <20240213121257.GI765010@ziepe.ca> <20240213121934.GA28726@willie-the-truck> <20240213125303.GJ765010@ziepe.ca> <20240213125951.GB28844@willie-the-truck> <20240213134726.GK765010@ziepe.ca> <20240213140900.GE28926@willie-the-truck> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20240213140900.GE28926@willie-the-truck> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240213_064225_662936_D8CEB754 X-CRM114-Status: GOOD ( 22.75 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Feb 13, 2024 at 02:09:00PM +0000, Will Deacon wrote: > Hey Jason, > > On Tue, Feb 13, 2024 at 09:47:26AM -0400, Jason Gunthorpe wrote: > > On Tue, Feb 13, 2024 at 12:59:52PM +0000, Will Deacon wrote: > > > > The typical kernel standard is to fix bugs in patches and only reach > > > > for a wholesale revert if the community is struggling with bug > > > > fixing. Dmitry already tested removing that hunk, Robin explained the > > > > issue, we understand the bug fix is to remove the > > > > arm_smmu_init_domain_context() call. Nothing justifies a full scale > > > > revert. > > > > > > I can't say I'm aware of any consensus for how to handle this, to be > > > completely honest with you. > > > > Well, I work in a lot of subsystems and this is a surprise to me and > > not something I've seen before. Fix the bug, move forward. Reverts are > > a cultural admission of failure. I use threats of a revert as a hammer > > to encourage people to pay attention to the bugs. I hardly ever > > actually revert things. What does reverting their code say to my > > submitters??? > > Huh. I guess I'm lucky never to have worked in a environment where that > is the case. In fact, my experience is quite the opposite: revert first > so that things get back to a working state and the developer/submitter > has some breathing room to rework the broken code. It's actually fairly > blameless if you get it right and when you have a half-functional CI it's > pretty much a necessity. Anyway, I digress... Fascinating, I am glad we had this discussion because I was pretty put off by this talk of revert in this and the other thread. Cultural differences! Thanks, Jason _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel