Below two commits should go into 2.6.27 2.6.28 2.6.29 stable as suggested by Len. 87ad57bacb25c3f24c54f142ef445f68277705f0 7d60e8ab0d5507229dfbdf456501cc378610fa01 The first commit can't be applied, below patch is updated which should apply to the branches. The second commit can apply directly. When AMD C1E is enabled, local APIC timer will stop even in C1. This patch uses broadcast ipi to replace local APIC timer in C1. http://bugzilla.kernel.org/show_bug.cgi?id=13233 [ impact: avoid boot hang in AMD CPU with C1E enabled ] Tested-by: Dmitry Lyzhyn <thisistempbox@xxxxxxxxx> Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx> --- drivers/acpi/processor_idle.c | 6 ++++++ 1 file changed, 6 insertions(+) Index: linux/drivers/acpi/processor_idle.c =================================================================== --- linux.orig/drivers/acpi/processor_idle.c 2009-06-02 09:27:53.000000000 +0800 +++ linux/drivers/acpi/processor_idle.c 2009-06-02 09:32:36.000000000 +0800 @@ -212,6 +212,9 @@ static void acpi_timer_check_state(int s struct acpi_processor_power *pwr = &pr->power; u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2; + if (boot_cpu_has(X86_FEATURE_AMDC1E)) + type = ACPI_STATE_C1; + /* * Check, if one of the previous states already marked the lapic * unstable @@ -648,6 +651,7 @@ static int acpi_processor_power_verify(s switch (cx->type) { case ACPI_STATE_C1: cx->valid = 1; + acpi_timer_check_state(i, pr, cx); break; case ACPI_STATE_C2: @@ -871,12 +875,14 @@ static int acpi_idle_enter_c1(struct cpu return 0; } + acpi_state_timer_broadcast(pr, cx, 1); t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); acpi_idle_do_entry(cx); t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); local_irq_enable(); cx->usage++; + acpi_state_timer_broadcast(pr, cx, 0); return ticks_elapsed_in_us(t1, t2); } -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html