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Cota" Content-Type: text/plain; charset="UTF-8" Received-SPF: pass client-ip=2607:f8b0:4864:20::1136; envelope-from=peter.maydell@linaro.org; helo=mail-yw1-x1136.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, T_SPF_TEMPERROR=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 Mon, 29 Sept 2025 at 20:08, Peter Xu wrote: > > Trap call_rcu1() to make sure it won't be invoked twice for one rcu head. > > Suggested-by: Peter Maydell > Signed-off-by: Peter Xu > --- > util/rcu.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/util/rcu.c b/util/rcu.c > index b703c86f15..9272fe5796 100644 > --- a/util/rcu.c > +++ b/util/rcu.c > @@ -307,6 +307,8 @@ static void *call_rcu_thread(void *opaque) > > void call_rcu1(struct rcu_head *node, void (*func)(struct rcu_head *node)) > { > + /* Avoid double rcu frees */ I would maybe have this say "Catch accidental attempts to use the same rcu node for two things at once", which isn't the same as a "double free" in the usual sense. > + assert(node->func == NULL); > node->func = func; > enqueue(node); > qatomic_inc(&rcu_call_count); thanks -- PMM