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[172.10.233.147]) by smtp.gmail.com with ESMTPSA id y84sm820819oig.36.2021.01.06.12.18.46 (version=TLS1 cipher=ECDHE-ECDSA-AES128-SHA bits=128/128); Wed, 06 Jan 2021 12:18:46 -0800 (PST) Date: Wed, 6 Jan 2021 12:18:36 -0800 (PST) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Andrea Arcangeli cc: Andrew Morton , Hugh Dickins , Alex Shi , Minchan Kim , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/mmap: replace if (cond) BUG() with BUG_ON() In-Reply-To: Message-ID: References: <1607743586-80303-1-git-send-email-alex.shi@linux.alibaba.com> <1607743586-80303-2-git-send-email-alex.shi@linux.alibaba.com> <20210106114620.5c221690f3a9cad7afcc3077@linux-foundation.org> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII 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 Wed, 6 Jan 2021, Andrea Arcangeli wrote: > > I'd be surprised if the kernel can boot with BUG_ON() defined as "do > {}while(0)" so I guess it doesn't make any difference. I had been afraid of that too, when CONFIG_BUG is not set: but I think it's actually "if (cond) do {} while (0)".