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Tue, 19 Apr 2022 23:50:36 -0700 (PDT) Received: from bobo.ozlabs.ibm.com ([203.221.203.144]) by smtp.gmail.com with ESMTPSA id x20-20020aa79574000000b005061f4782c5sm18481235pfq.183.2022.04.19.23.50.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 Apr 2022 23:50:36 -0700 (PDT) From: Nicholas Piggin To: pdbg@lists.ozlabs.org Date: Wed, 20 Apr 2022 16:49:40 +1000 Message-Id: <20220420065013.222816-7-npiggin@gmail.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220420065013.222816-1-npiggin@gmail.com> References: <20220420065013.222816-1-npiggin@gmail.com> MIME-Version: 1.0 Subject: [Pdbg] [PATCH v2 06/39] gdbserver: Document problem and workaround for client remote timeouts X-BeenThere: pdbg@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "mailing list for https://github.com/open-power/pdbg development" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nicholas Piggin Errors-To: pdbg-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Pdbg" gdbserver does not robustly deal with the gdb client timing out and re-sending packets. Signed-off-by: Nicholas Piggin --- README.md | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/README.md b/README.md index 40450e43..9ece33f9 100644 --- a/README.md +++ b/README.md @@ -553,6 +553,13 @@ $ gdb Debugging info: (gdb) set debug remote 10 +Long-running operations or high latency links: +The gdb client timeout defaults to 2 seconds after which it re-transmits +commands. The gdb server does not deal with this robustly today and this +can cause hangs and other unexpected results. If gdb client stops +responding, behaves strangely or complains about bad or unexpected remote +packets, try increasing the timeout. E.g., +(gdb) set remotetimeout 60 Notes: 1. DON'T RUN PDBG OVER FSI WHILE HOSTBOOT IS RUNNING. Weird things seem to