On Thu, May 10, 2018 at 03:28:48PM +0200, Igor Mammedov wrote:
On Fri, 27 Apr 2018 15:53:14 -0600
Ross Zwisler <ross.zwisler(a)linux.intel.com> wrote:
> Add a device command line option to allow the user to control the Platform
> Capabilities Structure in the virtualized NFIT.
> Signed-off-by: Ross Zwisler <ross.zwisler(a)linux.intel.com>
> docs/nvdimm.txt | 22 ++++++++++++++++++++++
> hw/acpi/nvdimm.c | 29 +++++++++++++++++++++++++----
> hw/mem/nvdimm.c | 28 ++++++++++++++++++++++++++++
> include/hw/mem/nvdimm.h | 6 ++++++
> 4 files changed, 81 insertions(+), 4 deletions(-)
> diff --git a/docs/nvdimm.txt b/docs/nvdimm.txt
> index e903d8bb09..13a2c15b70 100644
> --- a/docs/nvdimm.txt
> +++ b/docs/nvdimm.txt
> @@ -153,3 +153,25 @@ guest NVDIMM region mapping structure. This unarmed flag
> guest software that this vNVDIMM device contains a region that cannot
> accept persistent writes. In result, for example, the guest Linux
> NVDIMM driver, marks such vNVDIMM device as read-only.
> +Platform Capabilities
> +ACPI 6.2 Errata A added support for a new Platform Capabilities Structure
> +which allows the platform to communicate what features it supports related to
> +NVDIMM data durability. Users can provide a capabilities value to a guest via
> +the optional "cap" device command line option:
> + -device nvdimm,id=nvdimm1,memdev=mem1,cap=3
> +As of ACPI 6.2 Errata A, the following values are valid for the bottom two
> +2 - Memory Controller Flush to NVDIMM Durability on Power Loss Capable.
> +3 - CPU Cache Flush to NVDIMM Durability on Power Loss Capable.
> +For a complete list of the flags available please consult the ACPI spec.
> +These platform capabilities apply to the entire virtual platform, so it is
> +recommended that only one "cap" device command option be given per
> +machine. This value will apply to all NVDIMMs in the virtual platform.
This looks like it should be machine property instead of per device one,
you can get rid of static variable and mismatch check and a weird nvdimm CLI
option that implies that the option is per device.
Yep, that's much better. I have this implemented and ready to go.
Also an extra patch to for make check that will test setting
would be nice (an extra testcase in tests/bios-tables-test.c)
Hmm...I've been looking at this, and it doesn't look like there is any
verification around a lot of the ACPI tables (NFIT, SRAT, etc).
I've verified my patch by interacting with a guest with various settings - is
this good enough, or do you really want me to test the value (which I think
would just be "do I get out what I put in at the command line") via the unit
Thank you for the review.