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[86.9.19.6]) by smtp.gmail.com with ESMTPSA id z10sm410920wrg.69.2020.04.30.09.52.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Apr 2020 09:52:10 -0700 (PDT) Date: Thu, 30 Apr 2020 17:52:08 +0100 From: Daniel Thompson To: Douglas Anderson Cc: jason.wessel@windriver.com, gregkh@linuxfoundation.org, agross@kernel.org, kgdb-bugreport@lists.sourceforge.net, catalin.marinas@arm.com, linux-serial@vger.kernel.org, sumit.garg@linaro.org, corbet@lwn.net, mingo@redhat.com, will@kernel.org, hpa@zytor.com, tglx@linutronix.de, frowand.list@gmail.com, bp@alien8.de, bjorn.andersson@linaro.org, jslaby@suse.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 06/11] kgdb: Prevent infinite recursive entries to the debugger Message-ID: <20200430165208.7btqnsygf7kn3cso@holly.lan> References: <20200428211351.85055-1-dianders@chromium.org> <20200428141218.v3.6.I89de39f68736c9de610e6f241e68d8dbc44bc266@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200428141218.v3.6.I89de39f68736c9de610e6f241e68d8dbc44bc266@changeid> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 28, 2020 at 02:13:46PM -0700, Douglas Anderson wrote: > If we detect that we recursively entered the debugger we should hack > our I/O ops to NULL so that the panic() in the next line won't > actually cause another recursion into the debugger. The first line of > kgdb_panic() will check this and return. > > Signed-off-by: Douglas Anderson Reviewed-by: Daniel Thompson