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Tsirkin" , =?UTF-8?B?QWxleCBCZW5uw6ll?= , Fabiano Rosas , Paolo Bonzini , David Hildenbrand , Thomas Huth , Laurent Vivier , qemu-devel@nongnu.org, qemu-block@nongnu.org, qemu-ppc@nongnu.org, devel@daynix.com Content-Type: text/plain; charset="UTF-8" Received-SPF: pass client-ip=2607:f8b0:4864:20::b2b; envelope-from=peter.maydell@linaro.org; helo=mail-yb1-xb2b.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 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 Thu, 21 Aug 2025 at 15:28, Peter Xu wrote: > > On Thu, 21 Aug 2025 at 13:40, Peter Maydell wrote: > > > In memory_region_unref_subregion(), subregion->container is NULL. > > > > > > This is because in memory_region_del_subregion() we do: > > > > > > subregion->container = NULL; > > > > > > and then after that we call > > > memory_region_unref_subregion(subregion); > > > which dereferences subregion->container. > > > > > > Won't this always SEGV ? > Peter, could you try the v3 version patch 8/9 instead? > > https://lore.kernel.org/all/20240708-san-v3-8-b03f671c40c6@daynix.com/ > > I still prefer that one, and I hope that one doesn't have this issue. That one fails like this: qemu-system-arm: ../../system/memory.c:1799: memory_region_finalize: Assertion `!mr->container' failed. See the discussion on v2 (which was the same for this patch): https://lore.kernel.org/all/CAFEAcA9KTSjwF1rABpM5nv9UFuKqZZk6+Qo4PEF4+rTirNi5fQ@mail.gmail.com/ thanks -- PMM