[ldv-project] [BUG] might sleep functions in atomic context in stmmac_resume()

[Alexey Khoroshilov]

There are calls to might sleep functions in atomic context in
stmmac_resume():
- the first one is clk_prepare_enable(priv->stmmac_clk);
- the second one is stmmac_hw_setup()
-> init_dma_desc_rings()
  -> stmmac_init_rx_buffers()
    -> __netdev_alloc_skb(GFP_KERNEL)

What is the purpose of spin_lock_irqsave(&priv->lock, flags) section?
What does it protect against?

Found by Linux Driver Verification project (linuxtesting.org).

--
Alexey Khoroshilov
Linux Verification Center, ISPRAS
web: http://linuxtesting.org