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Crash in uxListRemove

Posted by bupthebroker on March 9, 2016

Hi, i have a problem with my FreeRtos 8.2 in the uxListRemove function:

Listt * const pxList = ( Listt * ) pxItemToRemove->pvContainer;

the pxList is NULL which causes a crash.

I noticed that inside xQueueGenericReceive a task can add itself to a wait list TWO times. The pvContainer pointer is set to NULL upon the first removal of the same task. The second removel will then crash.

if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE ) { ... vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait ); ... }

What could cause this?

Edit, i noticed that xQueueReset was called. This does not seem to clear the pxQueue->xTasksWaitingToReceive, is that correct? After the xQueueReset pxQueue->xTasksWaitingToReceive.uxNumberOfItems is 1, and the same task will add itselt the second time, bringing the pxQueue->xTasksWaitingToReceive.uxNumberOfItems value to 2.


Crash in uxListRemove

Posted by rtel on March 9, 2016

The most common cause of this type of data corruption is an invliad interrupt priority setting.

Which port are you using? Do you have configASSERT() defined? Have you read through the "my application does not run, what could be wrong?" FAQ item?

Crash in uxListRemove

Posted by bupthebroker on March 9, 2016

I am using pic32, i haven't used the configASSERT, i will see what it says..

Hmm, now it won't start at all: xTaskPriorityDisinherit: configASSERT( pxTCB->uxMutexesHeld );

Crash in uxListRemove

Posted by rtel on March 9, 2016

Are you trying to give a mutex from a task that does not hold the mutex?

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