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[130.111.218.23]) by smtp.gmail.com with ESMTPSA id f30-v6sm3506210qtf.50.2018.11.08.08.05.08 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 08 Nov 2018 08:05:08 -0800 (PST) From: Vince Weaver X-Google-Original-From: Vince Weaver Date: Thu, 8 Nov 2018 11:05:07 -0500 (EST) X-X-Sender: vince@macbook-air To: Vince Weaver cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin , Jiri Olsa , Namhyung Kim , torvalds@linux-foundation.org Subject: Re: perf: perf_fuzzer triggers NULL pointer dereference In-Reply-To: Message-ID: References: User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 8 Nov 2018, Vince Weaver wrote: > [91760.326510] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 > [91760.334876] PGD 0 P4D 0 > [91760.337596] Oops: 0000 [#1] SMP PTI > [91760.341332] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G W 4.20.0-rc1+ #119 > [91760.349816] Hardware name: LENOVO 10AM000AUS/SHARKBAY, BIOS FBKT72AUS 01/26/2014 > [91760.357723] RIP: 0010:perf_prepare_sample+0x82/0x4a0 so what's the best way to do the equivelent of addr2line on something like this, now that we aren't allowed to know the RIP anymore? I probably knew at one point but I've spent the last 3 months doing 6502 assembly language Demoscene coding and so apparently I've forgotten everything I once knew about x86_64 kernel interfaces. (As can be imagined, Demoscene coding work is a lot more mentally rewarding than perf_fuzzer work). Vince