From: Len Brown len.brown@intel.com
Under some conditions, MONITOR wakeups on Lunar Lake processors can be lost, resulting in significant user-visible delays.
Add LunarLake to X86_BUG_MONITOR so that wake_up_idle_cpu() always sends an IPI, avoiding this potential delay.
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219364
Cc: stable@vger.kernel.org # 6.11 Signed-off-by: Len Brown len.brown@intel.com --- v3 syntax tweak v2 leave smp_kick_mwait_play_dead() alone
arch/x86/kernel/cpu/intel.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index e7656cbef68d..4b5f3d052151 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -586,7 +586,9 @@ static void init_intel(struct cpuinfo_x86 *c) c->x86_vfm == INTEL_WESTMERE_EX)) set_cpu_bug(c, X86_BUG_CLFLUSH_MONITOR);
- if (boot_cpu_has(X86_FEATURE_MWAIT) && c->x86_vfm == INTEL_ATOM_GOLDMONT) + if (boot_cpu_has(X86_FEATURE_MWAIT) && + (c->x86_vfm == INTEL_ATOM_GOLDMONT || + c->x86_vfm == INTEL_LUNARLAKE_M)) set_cpu_bug(c, X86_BUG_MONITOR);
#ifdef CONFIG_X86_64