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[174.21.71.127]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21da3ea3b45sm87002455ad.97.2025.01.28.12.08.06 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 28 Jan 2025 12:08:07 -0800 (PST) Message-ID: <61b6b085-cc5e-4439-8af0-e51f45207a03@linaro.org> Date: Tue, 28 Jan 2025 12:08:05 -0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 3/9] cpus: Remove cpu from global queue after UNREALIZE completed To: =?UTF-8?Q?Philippe_Mathieu-Daud=C3=A9?= , qemu-devel@nongnu.org Cc: Peter Maydell , Yanan Wang , Eduardo Habkost , Harsh Prateek Bora , kvm@vger.kernel.org, Zhao Liu , =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= , Markus Armbruster , Igor Mammedov , Marcel Apfelbaum , Peter Xu , Paolo Bonzini References: <20250128142152.9889-1-philmd@linaro.org> <20250128142152.9889-4-philmd@linaro.org> Content-Language: en-US From: Richard Henderson In-Reply-To: <20250128142152.9889-4-philmd@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2607:f8b0:4864:20::634; envelope-from=richard.henderson@linaro.org; helo=mail-pl1-x634.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 1/28/25 06:21, Philippe Mathieu-Daudé wrote: > Previous commit removed the restriction on completing the full QDev > UNREALIZE step before removing vCPUs from global queue, it is now > safe to call cpu_list_remove() after accel_cpu_common_unrealize(). > > Signed-off-by: Philippe Mathieu-Daudé > --- > cpu-target.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/cpu-target.c b/cpu-target.c > index 667688332c9..11592e2583f 100644 > --- a/cpu-target.c > +++ b/cpu-target.c > @@ -172,12 +172,9 @@ void cpu_exec_unrealizefn(CPUState *cpu) > } > #endif > > - cpu_list_remove(cpu); > - /* > - * Now that the vCPU has been removed from the RCU list, we can call > - * accel_cpu_common_unrealize, which may free fields using call_rcu. > - */ > accel_cpu_common_unrealize(cpu); > + > + cpu_list_remove(cpu); > } I don't believe this is correct. Why would we have an unrealized cpu on the list? What's wrong with removing the cpu from the list before unrealize? r~