Subject: Re: [PATCH net v2] ipv6: fix data race in fib6_metric_set() using cmpxchg

From: Hangbin Liu <[email-masked]>
Date: Tue, 31 Mar 2026 01:34:21 +0000

On Sat, Mar 28, 2026 at 07:22:48PM +0800, Jiayuan Chen wrote:
> https://sashiko.dev/#/patchset/20260327-b4-fib6_metric_set-kmemleak-v2-1-366b2c78b5c2%40gmail.com
> 
> 
> The concern about reader paths (e.g., ip_dst_init_metrics, fib6_pmtu)
> lacking READ_ONCE()
> annotations is valid — if the compiler reloads from->fib6_metrics after
> inlining, it could produce
> an inconsistent pointer/flags combination in dst->_metrics, potentially
> leading to a refcount_dec
> on the read-only dst_default_metrics.

Thanks, I will fix the reader path separately in case I missed anything and
slow down this one's process.

Thanks
Hangbin