Re: [PATCH] irqchip/gic-v4.1: Use readx_poll_timeout_atomic() to fix sleep in atomic

From: Marc Zyngier
Date: Wed Jun 10 2020 - 11:02:58 EST


Hi Zenghui,

On 2020-06-10 14:59, Zenghui Yu wrote:
Hi Marc,

Sorry to ping you in the merge window, but ...

On 2020/6/5 13:23, Zenghui Yu wrote:
readx_poll_timeout() can sleep if @sleep_us is specified by the caller,
and is therefore unsafe to be used inside the atomic context, which is
this case when we use it to poll the GICR_VPENDBASER.Dirty bit in
irq_set_vcpu_affinity() callback.

this seems like an urgent thing to me. Without this patch, CPUs are
easily to get stuck on my board with GICv4.1 enabled. So it'd be good if
you can have a look and take this as a fix (if it is correct).

No worries. I've earmarked the patch for -rc1 already, just haven't got
a chance to build the branch yet (a bit busy on the KVM side).

I'll probably update the branch tonight or tomorrow.

Thanks,

M.
--
Jazz is not dead. It just smells funny...