Merge tag 'x86_urgent_for_v6.0-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Dave Hansen:

 - A performance fix for recent large AMD systems that avoids an ancient
   cpu idle hardware workaround

 - A new Intel model number. Folks like these upstream as soon as
   possible so that each developer doing feature development doesn't
   need to carry their own #define

 - SGX fixes for a userspace crash and a rare kernel warning

* tag 'x86_urgent_for_v6.0-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ACPI: processor idle: Practically limit "Dummy wait" workaround to old Intel systems
  x86/sgx: Handle VA page allocation failure for EAUG on PF.
  x86/sgx: Do not fail on incomplete sanitization on premature stop of ksgxd
  x86/cpu: Add CPU model numbers for Meteor Lake

1 files changed, 20 insertions, 3 deletions

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 16a1663d02d4..9f40917c49ef 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -531,10 +531,27 @@ static void wait_for_freeze(void)
 	/* No delay is needed if we are in guest */
 	if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
 		return;
+	/*
+	 * Modern (>=Nehalem) Intel systems use ACPI via intel_idle,
+	 * not this code.  Assume that any Intel systems using this
+	 * are ancient and may need the dummy wait.  This also assumes
+	 * that the motivating chipset issue was Intel-only.
+	 */
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
+		return;
 #endif
-	/* Dummy wait op - must do something useless after P_LVL2 read
-	   because chipsets cannot guarantee that STPCLK# signal
-	   gets asserted in time to freeze execution properly. */
+	/*
+	 * Dummy wait op - must do something useless after P_LVL2 read
+	 * because chipsets cannot guarantee that STPCLK# signal gets
+	 * asserted in time to freeze execution properly
+	 *
+	 * This workaround has been in place since the original ACPI
+	 * implementation was merged, circa 2002.
+	 *
+	 * If a profile is pointing to this instruction, please first
+	 * consider moving your system to a more modern idle
+	 * mechanism.
+	 */
 	inl(acpi_gbl_FADT.xpm_timer_block.address);
 }