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Date:   Mon, 28 Mar 2022 14:20:57 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Xiaomeng Tong <xiam0nd.tong@gmail.com>
Cc:     linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, nm@ti.com,
        rafael.j.wysocki@intel.com, sboyd@kernel.org,
        stable@vger.kernel.org, vireshk@kernel.org
Subject: Re: [PATCH] opp: fix a missing check on list iterator
Message-ID: <20220328085057.ikn3mcyz2gbftkg4@vireshk-i7>
References: <20220328031739.72togwws2u2rlluo@vireshk-i7>
 <20220328074322.25349-1-xiam0nd.tong@gmail.com>
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On 28-03-22, 15:43, Xiaomeng Tong wrote:
> No. the conditon to call opp_migrate_dentry(opp_dev, opp_table); is:
> if (!list_is_singular(&opp_table->dev_list)), 
> 
> while list_is_singlular is: !list_empty(head) && (head->next == head->prev);
> 
> so the condition is: list_empty(head) || (head->next != head->prev)
> 
> if the list is empty, the bug can be triggered.

List can't be empty here by design. It will be a huge bug in that
case, which should lead to crash somewhere.

-- 
viresh