Re: [PATCH v8 -tip 13/26] kernel/entry: Add support for core-wide protection of kernel-mode

From: Randy Dunlap
Date: Mon Oct 19 2020 - 23:42:15 EST


On 10/19/20 6:43 PM, Joel Fernandes (Google) wrote:

---
.../admin-guide/kernel-parameters.txt | 7 +
include/linux/entry-common.h | 2 +-
include/linux/sched.h | 12 +
kernel/entry/common.c | 25 +-
kernel/sched/core.c | 229 ++++++++++++++++++
kernel/sched/sched.h | 3 +
6 files changed, 275 insertions(+), 3 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3236427e2215..48567110f709 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4678,6 +4678,13 @@
sbni= [NET] Granch SBNI12 leased line adapter
+ sched_core_protect_kernel=

Needs a list of possible values after '=', along with telling us
what the default value/setting is.


+ [SCHED_CORE] Pause SMT siblings of a core running in
+ user mode, if at least one of the siblings of the core
+ is running in kernel mode. This is to guarantee that
+ kernel data is not leaked to tasks which are not trusted
+ by the kernel.
+


thanks.