The patch titled ACPI: move timer broadcast and pmtimer access before C3 arbiter shutdown has been added to the -mm tree. Its filename is acpi-move-timer-broadcast-and-pmtimer-access-before-c3-arbiter-shutdown.patch *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this ------------------------------------------------------ Subject: ACPI: move timer broadcast and pmtimer access before C3 arbiter shutdown From: Udo A. Steinberg <us15@xxxxxxxxxxxxxxxxxxxx> The chipset doc for IHC4 tells us: 1.In general, software should not attempt any non-posted accesses during arbiter disable except to the ICH4's power management registers. This implies that interrupt handlers for any unmasked hardware interrupts and SMI/NMI should check ARB_DIS status before reading from ICH devices. So it's not a good idea to access ICH devices after arbiter shut down. Signed-off-by: Udo A. Steinberg <us15@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Len Brown <lenb@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/acpi/processor_idle.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletion(-) diff -puN drivers/acpi/processor_idle.c~acpi-move-timer-broadcast-and-pmtimer-access-before-c3-arbiter-shutdown drivers/acpi/processor_idle.c --- a/drivers/acpi/processor_idle.c~acpi-move-timer-broadcast-and-pmtimer-access-before-c3-arbiter-shutdown +++ a/drivers/acpi/processor_idle.c @@ -989,6 +989,12 @@ static int acpi_idle_enter_c3(struct cpu return 0; } + /* + * Must be done before busmaster disable as we might need to + * access HPET ! + */ + acpi_state_timer_broadcast(pr, cx, 1); + /* disable bus master */ if (pr->flags.bm_check) { spin_lock(&c3_lock); @@ -1008,7 +1014,6 @@ static int acpi_idle_enter_c3(struct cpu /* Get start time (ticks) */ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); - acpi_state_timer_broadcast(pr, cx, 1); acpi_idle_do_entry(cx); t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); _ Patches currently in -mm which might be from us15@xxxxxxxxxxxxxxxxxxxx are acpi-move-timer-broadcast-and-pmtimer-access-before-c3-arbiter-shutdown.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html