Last edited one year ago

Networking troubleshooting grid

Applicable for STM32MP13x lines, STM32MP15x lines

Some typical issues related to the Networking feature are listed below. Solutions or debugging methods are proposed for these issues.

If your issue is not listed, try also looking in the articles in the Networking or troubleshooting grids categories.

Symptom Resolution
swapper/0: page allocation failure: order:0, mode:0x480020(GFP_ATOMIC)
[43154.580149] stm32-dwmac 5800a000.ethernet: fail to alloc skb entry 430
[<c0232144>] (warn_alloc) from [<c02332f4>] (__alloc_pages_nodemask+0x1018/0x144c)
[<c02332f4>] (__alloc_pages_nodemask) from [<c02803e4>] (new_slab+0x4f0/0x5c0)
[<c0282e94>] (kmem_cache_alloc) from [<c0844cac>] (__build_skb+0x28/0x98)
[<c0844cac>] (__build_skb) from [<c0844e6c>] (__netdev_alloc_skb+0xe8/0x138)
[<c0844e6c>] (__netdev_alloc_skb) from [<c06ad700>] (stmmac_rx+0x698/0xb90)

When the DDR is widely used, this issue could occurs if atomic allocation area is in contension. The solution would be to increase "vm.min_free_kbytes" but take care of not increasing too much this area to avoid OOM. Recommendation is min_free_kbytes = 5% of DDR size / <nr_cpus>