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([2600:1000:b079:1710:3c3b:2ce9:9489:b502]) by smtp.gmail.com with ESMTPSA id a19sm13439465qtk.56.2019.11.19.13.42.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 19 Nov 2019 13:42:28 -0800 (PST) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable From: Qian Cai Mime-Version: 1.0 (1.0) Subject: Re: [PATCH v4 01/10] kcsan: Add Kernel Concurrency Sanitizer infrastructure Date: Tue, 19 Nov 2019 16:42:26 -0500 Message-Id: References: Cc: LKMM Maintainers -- Akira Yokosawa , Alan Stern , Alexander Potapenko , Andrea Parri , Andrey Konovalov , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Boqun Feng , Borislav Petkov , Daniel Axtens , Daniel Lustig , Dave Hansen , David Howells , Dmitry Vyukov , "H. Peter Anvin" , Ingo Molnar , Jade Alglave , Joel Fernandes , Jonathan Corbet , Josh Poimboeuf , Luc Maranget , Mark Rutland , Nicholas Piggin , "Paul E. McKenney" , Peter Zijlstra , Thomas Gleixner , Will Deacon , Eric Dumazet , kasan-dev , linux-arch , "open list:DOCUMENTATION" , linux-efi@vger.kernel.org, Linux Kbuild mailing list , LKML , Linux Memory Management List , the arch/x86 maintainers In-Reply-To: To: Marco Elver X-Mailer: iPhone Mail (17A878) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > On Nov 19, 2019, at 2:54 PM, Marco Elver wrote: >=20 > Regardless of approach, my guess is that the complexity outweighs any > benefits this may provide in the end. Not only would a hypothetical > kernel that combines these be extremely slow, it'd also diminish the > practical value because testing and finding bugs would also be > impaired due to performance. On the other hand, it is valuable for distros to be able to select both for t= he debug kernel variant. Performance is usually not a major concern over the= re and could be migrated by other means like selecting powerful systems etc.=