Re: [RT PATCH v2] net/xfrm/xfrm_ipcomp: Protect scratch buffer with local_lock

From: Sebastian Andrzej Siewior
Date: Tue Aug 20 2019 - 04:28:15 EST


On 2019-08-19 14:27:31 [+0200], Juri Lelli wrote:
> This v2 applies to v4.19.59-rt24.

Looks good, I suggest to apply this to v4.19 and earlier.

For v5.2 and later (including upstream) please send a patch to simply
replace get_cpu() with smp_processor_id(). The reason is that get_cpu()
will not disable BH and according to the call path this function is
invoked in NAPI callback and the other sides does local_bh_disable().
Therefore the caller of this must ensure that BH is disabled and
disabling preemption is not enough.

Sebastian