[PATCH 0/1] nvme: Export CSTS register via sysfs

[Keith Busch]

On Wed, May 05, 2021 at 08:23:43PM +0000, Alan Adamson wrote:
> 
> 
> > On May 5, 2021, at 1:11 PM, Keith Busch <kbusch at kernel.org> wrote:
> > 
> > On Wed, May 05, 2021 at 06:40:54PM +0000, Alan Adamson wrote:
> >> Need to revisit this issue again.  In the original case we needed to
> >> get access to the csts register. We were able to move to using the
> >> ’state’ sysfs attribute.
> >> 
> >> We are now getting a similar request from our manufacturing team. They
> >> are using nvme-cli show-regs to assist debug. The ’state’ attribute is
> >> not sufficient and they want to use the production version of the
> >> kernel (which enables CONFIG_IO_STRICT_DEVMEM) rather than a special
> >> kernel. Ideally, we would want nvme-cli show-regs to work whether or
> >> not CONFIG_IO_STRICT_DEVMEM is configured. Other than exporting the
> >> registers thru sysfs attributes, is there any other mechanism to get
> >> show-regs the data it needs?
> > 
> > Append kernel parameter "iomem=relaxed”.
> 
> That requires the OS disk to be modified.  We would rather not do that.

Oh, that seems like a really good idea to me for a manufacturing
enviroment. There really is no other option other than modify the
kernel, which sounds much more invasive.