Subject: Re: [PATCH] bpf: Fix test_lru_sanity5() in test_lru_map.c

From: Daniel Borkmann <[email-masked]>
Date: Tue, 17 Jan 2017 10:07:32 +0100

On 01/17/2017 07:17 AM, Martin KaFai Lau wrote:
> test_lru_sanity5() fails when the number of online cpus
> is fewer than the number of possible cpus.  It can be
> reproduced with qemu by using cmd args "--smp cpus=2,maxcpus=8".
>
> The problem is the loop in test_lru_sanity5() is testing
> 'i' which is incorrect.
>
> This patch:
> 1. Make sched_next_online() always return -1 if it cannot
>     find a next cpu to schedule the process.
> 2. In test_lru_sanity5(), the parent process does
>     sched_setaffinity() first (through sched_next_online())
>     and the forked process will inherit it according to
>     the 'man sched_setaffinity'.
>
> Fixes: 5db58faf989f ("bpf: Add tests for the LRU bpf_htab")
> Reported-by: Daniel Borkmann <[email-masked]>
> Signed-off-by: Martin KaFai Lau <[email-masked]>

Looks good, thanks for fixing!

Acked-by: Daniel Borkmann <[email-masked]>

(Patch is against -net tree.)