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[2001:470:b8f6:1b::1]) by smtp.gmail.com with ESMTPSA id u66sm311468oie.17.2020.02.12.19.11.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Feb 2020 19:11:37 -0800 (PST) Received: from t560.minyard.net (unknown [IPv6:2001:470:b8f6:1b:e166:6491:dd75:4196]) by serve.minyard.net (Postfix) with ESMTPA id 54FB918004F; Thu, 13 Feb 2020 03:11:36 +0000 (UTC) From: minyard@acm.org To: Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Subject: [RFC PATCH 0/2] arm64 kgdb fixes for single stepping Date: Wed, 12 Feb 2020 21:11:29 -0600 Message-Id: <20200213031131.13255-1-minyard@acm.org> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I got a bug report about using kgdb on arm64, and it turns out it was fairly broken. Patch 2 has a description of what was going on. I am using a Marvell 8100 board. The following patches fix the problem, but probably not in the best way. They are what I hacked out to show the problems. I am not quite sure how this will interact with kprobes and hardware breakpoints which use the same code, but they would have been broken, too, so this is not making them any worse.