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Date: Fri, 29 Aug 2025 19:27:37 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Yue Haibing <yuehaibing@huawei.com>
Cc: <davem@davemloft.net>, <dsahern@kernel.org>, <edumazet@google.com>,
 <pabeni@redhat.com>, <horms@kernel.org>, <kuniyu@google.com>,
 <alex.aring@gmail.com>, <netdev@vger.kernel.org>,
 <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 net-next] ipv6: annotate data-races around
 devconf->rpl_seg_enabled
Message-ID: <20250829192737.680488a9@kernel.org>
In-Reply-To: <20250827081243.1701760-1-yuehaibing@huawei.com>
References: <20250827081243.1701760-1-yuehaibing@huawei.com>
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On Wed, 27 Aug 2025 16:12:43 +0800 Yue Haibing wrote:
> Also initializes extra1 and extra2 to SYSCTL_ZERO and SYSCTL_ONE
> respectively to avoid negative value writes, which may lead to
> unexpected results in ipv6_rpl_srh_rcv().

By unexpected results you mean that min() is intended to return 0
when either value is zero, but if one of the values is negative it
will in fact return non-zero?

That's a fair point, but I'm not sure whether we should be sending
that up as a fix. It's more of a sanity check that prevents
unintentional misconfiguration.. Please split this patch into two
separate ones, and send the minmax one without a Fixes tag.
Please include more of the explanation I have provided in the first
paragraph in the commit message, "unexpected results" is too vague
by itself.