[PATCH 1/1] nvme-fabrics: Generate uevent on namespace AENs

[Rao, Vinay]

-----Original Message-----
From: Chaitanya Kulkarni <Chaitanya.Kulkarni at wdc.com> 
Sent: Tuesday, May 4, 2021 4:52 AM
To: Rao, Vinay; Christoph Hellwig; Keith Busch
Cc: Belanger, Martin; Hayes, Stuart; Tarikere, Madhu; Martin Belanger; linux-nvme at lists.infradead.org; axboe at fb.com; sagi at grimberg.me
Subject: Re: [PATCH 1/1] nvme-fabrics: Generate uevent on namespace AENs


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On 5/3/21 00:21, Rao, Vinay wrote:
> Forcing RAE bit on all the log pages that kernel cares about is one of the option.
>
> Can we also think also think about an another mechanism where the kernel would generate uevent after kernel does a get log page. This would make kernel always to get the get log data first from the controller. 

to read empty log page ?

We are interested in these two events NVME_AER_NOTICE_NS_CHANGED and NVME_AER_NOTICE_ANA. 
-- NVME_AER_NOTICE_NS_CHANGED event would require the host software to do an nvme identify namespace to see the change in the namespace. 
-- NVME_AER_NOTICE_ANA event would require the host software to do a ANA LOG page command to get the ANA log page from the controller. Even if the ANA log page is sent from userland after the kernel sends it first the controller would still return the ANA log page. It will not return an empty log page.