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Sat, 10 Oct 2020 13:55:34 -0400 X-MC-Unique: QYmtt5OlNiau9SIU8B6cBg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B63AF1005E5D; Sat, 10 Oct 2020 17:55:31 +0000 (UTC) Received: from treble (ovpn-112-146.rdu2.redhat.com [10.10.112.146]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5036F60C13; Sat, 10 Oct 2020 17:55:23 +0000 (UTC) Date: Sat, 10 Oct 2020 12:55:20 -0500 From: Josh Poimboeuf To: Russell King - ARM Linux admin Subject: Re: [PATCH] arm:traps: Don't print stack or raw PC/LR values in backtraces Message-ID: <20201010175520.fczgnp66ey2vghkr@treble> References: <20201009075957.110017-1-nixiaoming@huawei.com> <20201009080849.GM1551@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201009080849.GM1551@shell.armlinux.org.uk> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201010_135541_937168_F355BA43 X-CRM114-Status: GOOD ( 20.26 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: wangle6@huawei.com, walken@google.com, amanieu@gmail.com, dima@arista.com, Xiaoming Ni , bigeasy@linutronix.de, vincent.whitchurch@axis.com, linux-kernel@vger.kernel.org, mingo@kernel.org, ben.dooks@codethink.co.uk, tglx@linutronix.de, viro@zeniv.linux.org.uk, luohaizheng@huawei.com, akpm@linux-foundation.org, ldufour@linux.ibm.com, will@kernel.org, christian.brauner@ubuntu.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Oct 09, 2020 at 09:08:50AM +0100, Russell King - ARM Linux admin wrote: > On Fri, Oct 09, 2020 at 03:59:57PM +0800, Xiaoming Ni wrote: > > Printing raw pointer values in backtraces has potential security > > implications and are of questionable value anyway. > > > > This patch follows x86 and arm64's lead and removes the "Exception stack:" > > dump from kernel backtraces: > > commit a25ffd3a6302a6 ("arm64: traps: Don't print stack or raw > > PC/LR values in backtraces") > > commit 0ee1dd9f5e7eae ("x86/dumpstack: Remove raw stack dump") > > commit bb5e5ce545f203 ("x86/dumpstack: Remove kernel text > > addresses from stack dump") > > > > Signed-off-by: Xiaoming Ni > > I am really not happy about this - it hurts at least my ability to > debug the kernel when people post oopses to the mailing list. If > people wish to make the kernel harder to debug, and are prepared > to be told "your kernel is undebuggable" then this patch is fine. At least on x86 we've had this for four years now, without any apparent harm to debugability. scripts/faddr2line helps. -- Josh _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel