Re: [PATCH net] net: hns: fix soft lockup when there is not enough memory

[David Miller]

From: Yonglong Liu <liuyonglong@xxxxxxxxxx>
Date: Thu, 16 Jan 2020 15:41:17 +0800

> When there is not enough memory and napi_alloc_skb() return NULL,
> the HNS driver will print error message, and than try again, if
> the memory is not enough for a while, huge error message and the
> retry operation will cause soft lockup.
> 
> When napi_alloc_skb() return NULL because of no memory, we can
> get a warn_alloc() call trace, so this patch deletes the error
> message. We already use polling mode to handle irq, but the
> retry operation will render the polling weight inactive, this
> patch just return budget when the rx is not completed to avoid
> dead loop.
> 
> Fixes: 36eedfde1a36 ("net: hns: Optimize hns_nic_common_poll for better performance")
> Fixes: b5996f11ea54 ("net: add Hisilicon Network Subsystem basic ethernet support")
> Signed-off-by: Yonglong Liu <liuyonglong@xxxxxxxxxx>

Applied and queued up for -stable.