Re: [PATCH 0/4] nvme-pci: support device coredump

From: Akinobu Mita
Date: Thu May 02 2019 - 23:38:50 EST


2019å5æ2æ(æ) 22:03 Keith Busch <keith.busch@xxxxxxxxx>:
>
> On Thu, May 02, 2019 at 05:59:17PM +0900, Akinobu Mita wrote:
> > This enables to capture snapshot of controller information via device
> > coredump machanism, and it helps diagnose and debug issues.
> >
> > The nvme device coredump is triggered before resetting the controller
> > caused by I/O timeout, and creates the following coredump files.
> >
> > - regs: NVMe controller registers, including each I/O queue doorbell
> > registers, in nvme-show-regs style text format.
>
> You're supposed to treat queue doorbells as write-only. Spec says:
>
> The host should not read the doorbell registers. If a doorbell register
> is read, the value returned is vendor specific.

OK. I'll exclude the doorbell registers from register dump. It will work
out without the information if we have snapshot of the queues.