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Date:   Mon, 26 Jul 2021 08:24:34 -0700
From:   Keith Busch <kbusch@kernel.org>
To:     shiva.linuxworks@gmail.com
Cc:     rjw@rjwysocki.net, pavel@ucw.cz, len.brown@intel.com,
        linux-pm@vger.kernel.org, axboe@fb.com, hch@lst.de,
        sagi@grimberg.me, linux-nvme@lists.infradead.org,
        linux-kernel@vger.kernel.org,
        Shivamurthy Shastri <sshivamurthy@micron.com>
Subject: Re: [PATCH v2 0/2] Abrupt Shutdown for NVMe SSD
Message-ID: <20210726152434.GA2024939@dhcp-10-100-145-180.wdc.com>
References: <20210726132223.1661-1-sshivamurthy@micron.com>
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On Mon, Jul 26, 2021 at 01:22:21PM +0000, shiva.linuxworks@gmail.com wrote:
> In the platform with a limited backup power supply, devices like NVMe
> SSD does unsafe shutdown.
> 
> These two patches address this issue by adding a power loss imminent
> flag. The platform will enable the power loss imminent flag if the
> platform's power is running on the limited backup power supply. During
> the shutdown, the driver checks this information and pwerforms the
> abrupt shutdown.

I think the pm framework and nvme usage are ok, but you need a platform
specific caller to set the new power loss flag before this should be
considered, otherwise this is just unreachable code.