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Date:   Fri, 11 Nov 2022 14:14:02 +0000
From:   Sudeep Holla <sudeep.holla@arm.com>
To:     Huisong Li <lihuisong@huawei.com>
Cc:     linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org,
        rafael@kernel.org, rafael.j.wysocki@intel.com,
        wanghuiqiang@huawei.com, zhangzekun11@huawei.com,
        wangxiongfeng2@huawei.com, tanxiaofei@huawei.com,
        guohanjun@huawei.com, xiexiuqi@huawei.com,
        wangkefeng.wang@huawei.com, huangdaode@huawei.com
Subject: Re: [PATCH V2 2/2] mailbox: pcc: fix 'pcc_chan_count' when fail to
 initialize PCC
Message-ID: <20221111141402.7cun26euzubpesjs@bogus>
References: <20221110015034.7943-1-lihuisong@huawei.com>
 <20221111024448.25012-1-lihuisong@huawei.com>
 <20221111024448.25012-3-lihuisong@huawei.com>
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Change $subject as
"mailbox: pcc: Reset pcc_chan_count to zero in case of PCC probe failure"

On Fri, Nov 11, 2022 at 10:44:48AM +0800, Huisong Li wrote:
> Currently, 'pcc_chan_count' is a non-zero value if PCC subspaces are parsed
> successfully and subsequent processes is failure during initializing PCC
> process. This may cause that pcc_mbox_request_channel() can still be
> executed successfully , which will misleads the caller that this channel is
> available.
>

I would reword this something like:
"Currently, 'pcc_chan_count' is remains set to a non-zero value if PCC
subspaces are parsed successfully but something else fail later during
the initial PCC probing phase. This will result in pcc_mbox_request_channel()
trying to access the resources that are not initialised or allocated and
may end up in a system crash.

Reset pcc_chan_count to 0 when the PCC probe fails in order to prevent
the possible issue as described above.
"

> Fixes: ce028702ddbc ("mailbox: pcc: Move bulk of PCCT parsing into pcc_mbox_probe")

Other than that,

Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>

-- 
Regards,
Sudeep