Merge tag 'x86_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:

 - Fix a couple of SWAPGS fencing issues in the x86 entry code

 - Use the proper operand types in __{get,put}_user() to prevent
   truncation in SEV-ES string io

 - Make sure the kernel mappings are present in trampoline_pgd in order
   to prevent any potential accesses to unmapped memory after switching
   to it

 - Fix a trivial list corruption in objtool's pv_ops validation

 - Disable the clocksource watchdog for TSC on platforms which claim
   that the TSC is constant, doesn't stop in sleep states, CPU has TSC
   adjust and the number of sockets of the platform are max 2, to
   prevent erroneous markings of the TSC as unstable.

 - Make sure TSC adjust is always checked not only when going idle

 - Prevent a stack leak by initializing struct _fpx_sw_bytes properly in
   the FPU code

 - Fix INTEL_FAM6_RAPTORLAKE define naming to adhere to the convention

* tag 'x86_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/xen: Add xenpv_restore_regs_and_return_to_usermode()
  x86/entry: Use the correct fence macro after swapgs in kernel CR3
  x86/entry: Add a fence for kernel entry SWAPGS in paranoid_entry()
  x86/sev: Fix SEV-ES INS/OUTS instructions for word, dword, and qword
  x86/64/mm: Map all kernel memory into trampoline_pgd
  objtool: Fix pv_ops noinstr validation
  x86/tsc: Disable clocksource watchdog for TSC on qualified platorms
  x86/tsc: Add a timer to make sure TSC_adjust is always checked
  x86/fpu/signal: Initialize sw_bytes in save_xstate_epilog()
  x86/cpu: Drop spurious underscore from RAPTOR_LAKE #define

1 files changed, 41 insertions, 0 deletions

diff --git a/arch/x86/kernel/tsc_sync.c b/arch/x86/kernel/tsc_sync.c
index 50a4515fe0ad..9452dc9664b5 100644
--- a/arch/x86/kernel/tsc_sync.c
+++ b/arch/x86/kernel/tsc_sync.c
@@ -30,6 +30,7 @@ struct tsc_adjust {
 };
 
 static DEFINE_PER_CPU(struct tsc_adjust, tsc_adjust);
+static struct timer_list tsc_sync_check_timer;
 
 /*
  * TSC's on different sockets may be reset asynchronously.
@@ -77,6 +78,46 @@ void tsc_verify_tsc_adjust(bool resume)
 	}
 }
 
+/*
+ * Normally the tsc_sync will be checked every time system enters idle
+ * state, but there is still caveat that a system won't enter idle,
+ * either because it's too busy or configured purposely to not enter
+ * idle.
+ *
+ * So setup a periodic timer (every 10 minutes) to make sure the check
+ * is always on.
+ */
+
+#define SYNC_CHECK_INTERVAL		(HZ * 600)
+
+static void tsc_sync_check_timer_fn(struct timer_list *unused)
+{
+	int next_cpu;
+
+	tsc_verify_tsc_adjust(false);
+
+	/* Run the check for all onlined CPUs in turn */
+	next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
+	if (next_cpu >= nr_cpu_ids)
+		next_cpu = cpumask_first(cpu_online_mask);
+
+	tsc_sync_check_timer.expires += SYNC_CHECK_INTERVAL;
+	add_timer_on(&tsc_sync_check_timer, next_cpu);
+}
+
+static int __init start_sync_check_timer(void)
+{
+	if (!cpu_feature_enabled(X86_FEATURE_TSC_ADJUST) || tsc_clocksource_reliable)
+		return 0;
+
+	timer_setup(&tsc_sync_check_timer, tsc_sync_check_timer_fn, 0);
+	tsc_sync_check_timer.expires = jiffies + SYNC_CHECK_INTERVAL;
+	add_timer(&tsc_sync_check_timer);
+
+	return 0;
+}
+late_initcall(start_sync_check_timer);
+
 static void tsc_sanitize_first_cpu(struct tsc_adjust *cur, s64 bootval,
 				   unsigned int cpu, bool bootcpu)
 {