Re: [PATCH v2 07/21] coco/tdx-host: Expose P-SEAMLDR information via sysfs

[dan.j.williams]

Sagi Shahar wrote:
> On Tue, Sep 30, 2025 at 9:55 PM Chao Gao <chao.gao@xxxxxxxxx> wrote:
> >
> > TDX Module updates require userspace to select the appropriate module
> > to load. Expose necessary information to facilitate this decision. Two
> > values are needed:
> >
> > - P-SEAMLDR version: for compatibility checks between TDX Module and
> >                      P-SEAMLDR
> > - num_remaining_updates: indicates how many updates can be performed
> >
> > Expose them as tdx-host device attributes.
> >
> > Note that P-SEAMLDR sysfs nodes are hidden when INTEL_TDX_MODULE_UPDATE
> > isn't enabled or when P-SEAMLDR isn't loaded by BIOS, both of which
> > cause seamldr_get_info() to return NULL.
> >
> > Signed-off-by: Chao Gao <chao.gao@xxxxxxxxx>
> > Tested-by: Farrah Chen <farrah.chen@xxxxxxxxx>
> > ---
> >  .../ABI/testing/sysfs-devices-faux-tdx-host   | 25 ++++++++
> >  drivers/virt/coco/tdx-host/tdx-host.c         | 63 ++++++++++++++++++-
> >  2 files changed, 87 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/ABI/testing/sysfs-devices-faux-tdx-host b/Documentation/ABI/testing/sysfs-devices-faux-tdx-host
> 
> Trying to apply this patch locally fails because
> sysfs-devices-faux-tdx-host does not exist. There are also conflicts
> around drivers/virt/coco/tdx-host/tdx-host.c.
> 
> I'm looking at the base commit specified in the cover letter [1] but
> even the current head of the tsm/tdx tree [2] doesn't have the
> sysfs-devices-faux-tdx-host file. Are there any other dependencies for
> this series?

I hit the same head scratcher, but then realized that Chao did say that
you also need to apply:

https://lore.kernel.org/linux-coco/20251001022309.277238-1-chao.gao@xxxxxxxxx

...so:

git checkout -b $branch 9332e088937f
b4 shazam 20251001022309.277238-1-chao.gao@xxxxxxxxx
b4 shazam 20251001025442.427697-1-chao.gao@xxxxxxxxx

...works for me.