This is a note to let you know that I've just added the patch titled

    ACPI / processor: Fix failure of loading acpi-cpufreq driver

to the 3.14-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     acpi-processor-fix-failure-of-loading-acpi-cpufreq-driver.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 4985c32ee4241d1aba1beeac72294faa46aaff10 Mon Sep 17 00:00:00 2001
From: Lan Tianyu <[email protected]>
Date: Wed, 30 Apr 2014 15:46:33 +0800
Subject: ACPI / processor: Fix failure of loading acpi-cpufreq driver

From: Lan Tianyu <[email protected]>

commit 4985c32ee4241d1aba1beeac72294faa46aaff10 upstream.

According commit d640113fe (ACPI: processor: fix acpi_get_cpuid for UP
processor),  BIOS may not provide _MAT or MADT tables and acpi_get_apicid()
always returns -1. For these cases, original code will pass apic_id with
vaule of -1 to acpi_map_cpuid() and it will check the acpi_id. If acpi_id
is equal to zero, ignores apic_id and return zero for CPU0.

Commit b981513 (ACPI / scan: bail out early if failed to parse APIC
ID for CPU) changed the behavior. Return ENODEV when find apic_id is
less than zero after calling acpi_get_apicid(). This causes acpi-cpufreq
driver fails to be loaded on some machines. This patch is to fix it.

Fixes: b981513f806d (ACPI / scan: bail out early if failed to parse APIC ID for 
CPU)
References: https://bugzilla.kernel.org/show_bug.cgi?id=73781
Reported-and-tested-by: KATO Hiroshi <[email protected]>
Reported-and-tested-by: Stuart Foster <[email protected]>
Signed-off-by: Lan Tianyu <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/acpi/acpi_processor.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -170,6 +170,9 @@ static int acpi_processor_hotadd_init(st
        acpi_status status;
        int ret;
 
+       if (pr->apic_id == -1)
+               return -ENODEV;
+
        status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
        if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
                return -ENODEV;
@@ -260,10 +263,8 @@ static int acpi_processor_get_info(struc
        }
 
        apic_id = acpi_get_apicid(pr->handle, device_declaration, pr->acpi_id);
-       if (apic_id < 0) {
+       if (apic_id < 0)
                acpi_handle_debug(pr->handle, "failed to get CPU APIC ID.\n");
-               return -ENODEV;
-       }
        pr->apic_id = apic_id;
 
        cpu_index = acpi_map_cpuid(pr->apic_id, pr->acpi_id);


Patches currently in stable-queue which might be from [email protected] are

queue-3.14/acpi-processor-fix-failure-of-loading-acpi-cpufreq-driver.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to