4.13-stable review patch. If anyone has any objections, please let me know.
------------------ From: Hans de Goede <[email protected]> commit 594a30fb12424717a41c62323d2a8bf167dbccad upstream. When booting 4.13 on a VirtualBox VM on a Skylake host the following error shows up in the logs: [ 0.000000] [Firmware Bug]: TSC_DEADLINE disabled due to Errata; please update microcode to version: 0xb2 (or later) This is caused by apic_check_deadline_errata() only checking CPU model and not the X86_FEATURE_TSC_DEADLINE_TIMER flag (which VirtualBox does NOT export to the guest), combined with VirtualBox not exporting the micro-code version to the guest. This commit adds a check for X86_FEATURE_TSC_DEADLINE_TIMER to apic_check_deadline_errata(), silencing this error on VirtualBox VMs. Signed-off-by: Hans de Goede <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Cc: Frank Mehnert <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Michael Thayer <[email protected]> Cc: Michal Necasek <[email protected]> Cc: Peter Zijlstra <[email protected]> Fixes: bd9240a18e ("x86/apic: Add TSC_DEADLINE quirk due to errata") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/kernel/apic/apic.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -599,9 +599,13 @@ static const struct x86_cpu_id deadline_ static void apic_check_deadline_errata(void) { - const struct x86_cpu_id *m = x86_match_cpu(deadline_match); + const struct x86_cpu_id *m; u32 rev; + if (!boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) + return; + + m = x86_match_cpu(deadline_match); if (!m) return;
