[Mesh Segmentation] Out of segment buffers -12 when packet is larger than 12

[APochieroTH]

Hi, I'm working on Bluetooth mesh project. The network has 2 node for now:

1. one sensor using nrf5340dk
2. one sink for data collection using nrf52840 inside a Fanstel BT840XE

the sensor acquires events by creating a 16-byte packet, so it is necessary to segment it, but I got this error.

Following the code, it seems not a problem of space but of time since the k_mem_slab_alloc defined in mem_slab.c fails here:

	} else if (K_TIMEOUT_EQ(timeout, K_NO_WAIT)) {
		/* don't wait for a free block to become available */
		*mem = NULL;
		result = -ENOMEM;
	}

I'm trying different values of the following configurations, but without results
CONFIG_BT_MESH_ADV_BUF_COUNT=10
CONFIG_BT_MESH_TX_SEG_MAX=10
CONFIG_BT_MESH_TX_SEG_MSG_COUNT=1
CONFIG_BT_MESH_SEG_BUFS=1024

CONFIG_BT_L2CAP_RX_MTU=256
CONFIG_BT_L2CAP_TX_MTU=256
CONFIG_BT_L2CAP_TX_BUF_COUNT=5

CONFIG_BT_HCI_TX_STACK_SIZE=640

Decreasing the packet size to <11 bytes works fine and the sink receives the packet.

Any idea?

[APochieroTH]

I followed the code and it seems just a matter of byte order of tx buffer.

Thanks anyway