x86/sev: Create snp_prepare()

Browse source

In preparation for delayed SNP initialization, create a function snp_prepare()
that does the necessary architecture setup.  Export this function for the ccp
module to allow it to do the setup as necessary.

Introduce a cpu_read_lock/unlock() wrapper around the MFDM and SNP enable.
While CPU hotplug is not supported, this makes sure that the bit setting
happens on the same set of CPUs in both cases.

This improvement was suggested by Sashiko:

  https://sashiko.dev/#/patchset/20260324161301.1353976-1-tycho%40kernel.org

Also move {mfd,snp}_enable() out of the __init section, since these will be
called later.

Signed-off-by: Tycho Andersen (AMD) <tycho@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://patch.msgid.link/20260326161110.1764303-3-tycho@kernel.org

...

This commit is contained in:

Tycho Andersen (AMD) 2026-03-26 10:11:05 -06:00 • committed by Borislav Petkov (AMD)

parent 9c016c3f49

commit ca2ca373ec

2 changed files with 32 additions and 19 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

2

arch/x86/include/asm/sev.h

View file

49

arch/x86/virt/svm/sev.c

View file