[Nios II] Nios crashes if allocate memory during DMA transfert

Good morning,

I have a tricky problem. I tried everything I could but I can't figure out why my nios crashes.

I will explain you my problem.

I continually send fix size data with DMA to a SPI bus, when the dma transfert is complete, I send back the same data again and again. During that time, I receive on another SPI but without DMA data that I treat. Like they is a lot of them, I use dynamic allocation to store this data.

When all of this data are received, I change my DMA read address (ones the last transfer is complete) to them.

During this operation, my nios crash.

If I stop DMA transfert during receiving the other data, all work fine.

Do you have any suggestion ? Something I can test ?

Thank you

(Sorry for my bad english)

Flandroid