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[209.85.220.65]) by mx.google.com with SMTPS id n203sor721051wma.16.2019.01.28.17.42.04 for (Google Transport Security); Mon, 28 Jan 2019 17:42:04 -0800 (PST) Received-SPF: pass (google.com: domain of rientjes@google.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b="PFO/i6rh"; spf=pass (google.com: domain of rientjes@google.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=rientjes@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=CgA3sRNVMXk7js4c/E/CVOZKEVaE8DANGoI5NS4jIsA=; b=PFO/i6rhgf+YNrmRAo/R4/wZcZPGj6tRLfu+GLooakQVPwy4w3hgE1wFIEOX3TUidu FDuZuRhUsqVyTdGt7/Sbog4uLx+au2Wc+ki1mv2g4elLshnxy4VunOiv1wZdKdmDEooj JOvh0JdwciQX49Q6T7hVZg6bYAK8Sh6VQ46xUoP9EuImPbiODZTOhm75d0956bAayfRZ kiY6mkHGWMbxymUPtEmdYUaCiTnTc6R/Ad8Yuy+WeYXZNTn9WVnn6rPKPKbjEeiC1ah0 ICDZMIsGrJvVazGVIpyYvnx1jfv4Z14alRWHdurPDC80P5jlxJYuua66USDLCuGzzmM8 WKxw== X-Google-Smtp-Source: ALg8bN6BYzwni8B73SnaSoCgIxcAaI59FvHE+qVEYDBAH8vUdjEBNZ7mKcIu14vwd6BG6o617Hezqg== X-Received: by 2002:a1c:bdc5:: with SMTP id n188mr20341571wmf.69.1548726123691; Mon, 28 Jan 2019 17:42:03 -0800 (PST) Received: from [2620:15c:17:3:3a5:23a7:5e32:4598] ([2620:15c:17:3:3a5:23a7:5e32:4598]) by smtp.gmail.com with ESMTPSA id h1sm1237956wmb.0.2019.01.28.17.42.00 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 28 Jan 2019 17:42:02 -0800 (PST) Date: Mon, 28 Jan 2019 17:41:59 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Miles Chen cc: Christoph Lameter , Pekka Enberg , Joonsoo Kim , Andrew Morton , Jonathan Corbet , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org Subject: Re: [PATCH v2] mm/slub: introduce SLAB_WARN_ON_ERROR In-Reply-To: <1548313223-17114-1-git-send-email-miles.chen@mediatek.com> Message-ID: References: <1548313223-17114-1-git-send-email-miles.chen@mediatek.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) 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 Thu, 24 Jan 2019, miles.chen@mediatek.com wrote: > From: Miles Chen > > When debugging slab errors in slub.c, sometimes we have to trigger > a panic in order to get the coredump file. Add a debug option > SLAB_WARN_ON_ERROR to toggle WARN_ON() when the option is set. > Wouldn't it be better to enable/disable this for all slab caches instead of individual caches at runtime? I'm not sure excluding some caches because you know they'll WARN and trigger panic_on_warn unnecessarily is valid since it could be enabled for that cache as well through this interface.