From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40458) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dL0EF-0000D6-VE for qemu-devel@nongnu.org; Wed, 14 Jun 2017 00:48:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dL0EF-0004yA-Av for qemu-devel@nongnu.org; Wed, 14 Jun 2017 00:48:27 -0400 Sender: Richard Henderson References: <20170609170100.3599-1-alex.bennee@linaro.org> <20170609170100.3599-4-alex.bennee@linaro.org> <87vao4b4z5.fsf@linaro.org> <9776b437-90b4-f2c2-4a0c-c1c6585379bf@twiddle.net> <20170611050730.GA12317@flamenco> <20170613225352.GA26288@flamenco> From: Richard Henderson Message-ID: Date: Tue, 13 Jun 2017 21:48:17 -0700 MIME-Version: 1.0 In-Reply-To: <20170613225352.GA26288@flamenco> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] target/aarch64: exit to main loop after handling MSR List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Emilio G. Cota" , =?UTF-8?Q?Alex_Benn=c3=a9e?= Cc: peter.maydell@linaro.org, pbonzini@redhat.com, edgar.iglesias@xilinx.com, qemu-devel@nongnu.org, Peter Crosthwaite , "open list:ARM" On 06/13/2017 03:53 PM, Emilio G. Cota wrote: > The appended fixes it for me. Can you please test? > [ apply with `git am --scissors' ] > > Thanks, > > Emilio > > ---- 8< ---- > > Commit e75449a3 ("target/aarch64: optimize indirect branches") causes > a regression by which aarch64 guests freeze under TCG with -smp > 1, > even with `-accel accel=tcg,thread=single' (i.e. MTTCG disabled). > > I isolated the problem to the MSR handler. This patch forces an exit > after the handler is executed, which fixes the regression. Why would that be? The cpu_get_tb_cpu_state within helper_lookup_tb_ptr is supposed to read the new state that the msr handler would have installed. r~