[tip: x86/core] x86/bugs: Add retbleed=force

[tip-bot2 for Peter Zijlstra (Intel)]

The following commit has been merged into the x86/core branch of tip:

Commit-ID:     5c9a92dec3235b0c1d51e92860f8014753161593
Gitweb:        https://git.kernel.org/tip/5c9a92dec3235b0c1d51e92860f8014753161593
Author:        Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
AuthorDate:    Mon, 17 Oct 2022 16:41:20 +02:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Mon, 17 Oct 2022 16:41:20 +02:00

x86/bugs: Add retbleed=force

Debug aid, allows running retbleed=force,stuff on non-affected uarchs

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 arch/x86/kernel/cpu/bugs.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index e6c23ea..b307b83 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -838,6 +838,8 @@ static int __init retbleed_parse_cmdline(char *str)
 			retbleed_cmd = RETBLEED_CMD_STUFF;
 		} else if (!strcmp(str, "nosmt")) {
 			retbleed_nosmt = true;
+		} else if (!strcmp(str, "force")) {
+			setup_force_cpu_bug(X86_BUG_RETBLEED);
 		} else {
 			pr_err("Ignoring unknown retbleed option (%s).", str);
 		}