From 2203d6ed448ff3b777ee6bb614a53e686b483e5b Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 18 Nov 2005 07:29:51 -0800 Subject: [PATCH] Fix ACPI processor power block initialization Properly clear the memory, and set "pr->flags.power" only if a C2 or deeper state is valid (to make the code match both the comment and previous behaviour). This fixes a boot-time lockup reported by Maneesh Soni when using "maxcpus=1". Acked-by: Maneesh Soni Signed-off-by: Linus Torvalds --- drivers/acpi/processor_idle.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 573b6a97bb1..70d8a6ec092 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -514,8 +514,6 @@ static int acpi_processor_set_power_policy(struct acpi_processor *pr) static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) { - int i; - ACPI_FUNCTION_TRACE("acpi_processor_get_power_info_fadt"); if (!pr) @@ -524,8 +522,7 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) if (!pr->pblk) return_VALUE(-ENODEV); - for (i = 0; i < ACPI_PROCESSOR_MAX_POWER; i++) - memset(pr->power.states, 0, sizeof(struct acpi_processor_cx)); + memset(pr->power.states, 0, sizeof(pr->power.states)); /* if info is obtained from pblk/fadt, type equals state */ pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; @@ -555,13 +552,9 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) static int acpi_processor_get_power_info_default_c1(struct acpi_processor *pr) { - int i; - ACPI_FUNCTION_TRACE("acpi_processor_get_power_info_default_c1"); - for (i = 0; i < ACPI_PROCESSOR_MAX_POWER; i++) - memset(&(pr->power.states[i]), 0, - sizeof(struct acpi_processor_cx)); + memset(pr->power.states, 0, sizeof(pr->power.states)); /* if info is obtained from pblk/fadt, type equals state */ pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; @@ -873,7 +866,8 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr) for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { if (pr->power.states[i].valid) { pr->power.count = i; - pr->flags.power = 1; + if (pr->power.states[i].type >= ACPI_STATE_C2) + pr->flags.power = 1; } } -- 2.41.0