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5b83e820d2
- Reason: A task and B interrupt indirectly access the shared resource pxDelayedTaskList without proper security protection, leading to further crash. A task uses xEventGroupSetBits() to access the pxDelayedTaskList resource: xEventGroupSetBits() -> vTaskRemoveFromUnorderedEventList() -> uxListRemove() -> pxList, where pxList is the pxDelayedTaskList. At this point, another B interrupt is triggered (xEventGroupSetBits only suspends task scheduling and does not disable interrupts) and also accesses the pxDelayedTaskList resource: MacIsrSigPostDefHdl() -> __wifi_queue_send_from_isr() -> xQueueGenericSendFromISR() -> xTaskRemoveFromEventList() -> prvResetNextTaskUnblockTime() -> pxDelayedTaskList. This leads to an unsafe access to the pxDelayedTaskList resource by two entities, causing subsequent crash exceptions. - Fix: Modify the timing of the call to prvResetNextTaskUnblockTime() within xTaskRemoveFromEventList from unconditional execution to only execute when task scheduling is enabled. This way, when the B interrupt reaches xTaskRemoveFromEventList, it will not call prvResetNextTaskUnblockTime to access the pxDelayedTaskList resource (due to task scheduling being disabled). After the B interrupt execution is complete and control returns to A task, xTaskResumeAll() will be called, and then prvResetNextTaskUnblockTime() will update the pxDelayedTaskList resource again.