From a664ec9158eeddd75121d39c9a0758016097fa96 Mon Sep 17 00:00:00 2001 From: Rodrigo Branco Date: Tue, 3 Jan 2023 14:17:51 -0600 Subject: [PATCH] x86/bugs: Flush IBP in ib_prctl_set() We missed the window between the TIF flag update and the next reschedule. Signed-off-by: Rodrigo Branco Reviewed-by: Borislav Petkov (AMD) Signed-off-by: Ingo Molnar Cc: --- 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 d970ddb..bca0bd8 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1981,6 +1981,8 @@ static int ib_prctl_set(struct task_struct *task, unsigned long ctrl) if (ctrl == PR_SPEC_FORCE_DISABLE) task_set_spec_ib_force_disable(task); task_update_spec_tif(task); + if (task == current) + indirect_branch_prediction_barrier(); break; default: return -ERANGE; -- 2.7.4