From accd846698439ba18250e8fd5681af280446b853 Mon Sep 17 00:00:00 2001
From: Andrej Gelenberg <andrej.gelenberg@udo.edu>
Date: Fri, 14 May 2010 15:15:58 -0700
Subject: [PATCH 1/6] [CPUFREQ] revert "[CPUFREQ] remove rwsem lock from
 CPUFREQ_GOV_STOP call (second call site)"

395913d0b1db37092ea3d9d69b832183b1dd84c5 ("[CPUFREQ] remove rwsem lock
from CPUFREQ_GOV_STOP call (second call site)") is not needed, because
there is no rwsem lock in cpufreq_ondemand and cpufreq_conservative
anymore.  Lock should not be released until the work done.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=1594

Signed-off-by: Andrej Gelenberg <andrej.gelenberg@udo.edu>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Dave Jones <davej@redhat.com>
---
 drivers/cpufreq/cpufreq.c | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 063b2184caf55..8f22ce1ea6844 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1762,17 +1762,8 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
 			dprintk("governor switch\n");
 
 			/* end old governor */
-			if (data->governor) {
-				/*
-				 * Need to release the rwsem around governor
-				 * stop due to lock dependency between
-				 * cancel_delayed_work_sync and the read lock
-				 * taken in the delayed work handler.
-				 */
-				unlock_policy_rwsem_write(data->cpu);
+			if (data->governor)
 				__cpufreq_governor(data, CPUFREQ_GOV_STOP);
-				lock_policy_rwsem_write(data->cpu);
-			}
 
 			/* start new governor */
 			data->governor = policy->governor;

From 6f90388ac98e8cb2c63e307ffb13871a6b87f29b Mon Sep 17 00:00:00 2001
From: Xiaotian Feng <dfeng@redhat.com>
Date: Tue, 20 Jul 2010 20:11:02 +0800
Subject: [PATCH 2/6] [CPUFREQ] fix memory leak in cpufreq_add_dev

We didn't free policy->related_cpus in error path err_unlock_policy.
This is catched by following kmemleak report:

unreferenced object 0xffff88022a0b96d0 (size 512):
  comm "modprobe", pid 886, jiffies 4294689177 (age 780.694s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff8111ebe5>] create_object+0x186/0x281
    [<ffffffff814fad4f>] kmemleak_alloc+0x60/0xa7
    [<ffffffff8111127a>] kmem_cache_alloc_node_notrace+0x120/0x142
    [<ffffffff81262e4f>] alloc_cpumask_var_node+0x2c/0xd7
    [<ffffffff81262f0b>] alloc_cpumask_var+0x11/0x13
    [<ffffffff81262f1c>] zalloc_cpumask_var+0xf/0x11
    [<ffffffff8140fac0>] cpufreq_add_dev+0x11f/0x547
    [<ffffffff81334bda>] sysdev_driver_register+0xc2/0x11d
    [<ffffffff8140e334>] cpufreq_register_driver+0xcb/0x1b8
    [<ffffffffa032e040>] 0xffffffffa032e040
    [<ffffffff810021ba>] do_one_initcall+0x5e/0x15c
    [<ffffffff81087f94>] sys_init_module+0xa6/0x1e6
    [<ffffffff81009bc2>] system_call_fastpath+0x16/0x1b
    [<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Dave Jones <davej@redhat.com>
---
 drivers/cpufreq/cpufreq.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 8f22ce1ea6844..938b74ea9ffbe 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1077,6 +1077,7 @@ static int cpufreq_add_dev(struct sys_device *sys_dev)
 
 err_unlock_policy:
 	unlock_policy_rwsem_write(cpu);
+	free_cpumask_var(policy->related_cpus);
 err_free_cpumask:
 	free_cpumask_var(policy->cpus);
 err_free_policy:

From 47f8bcf362410b631a4d99ff5c79ec6b9dd3ace6 Mon Sep 17 00:00:00 2001
From: Matthew Garrett <mjg@redhat.com>
Date: Tue, 20 Jul 2010 13:52:00 -0400
Subject: [PATCH 3/6] [CPUFREQ] pcc driver should check for pcch method before
 calling _OSC

The pcc specification documents an _OSC method that's incompatible with the
one defined as part of the ACPI spec. This shouldn't be a problem as both
are supposed to be guarded with a UUID. Unfortunately approximately nobody
(including HP, who wrote this spec) properly check the UUID on entry to the
_OSC call. Right now this could result in surprising behaviour if the pcc
driver performs an _OSC call on a machine that doesn't implement the pcc
specification. Check whether the PCCH method exists first in order to reduce
this probability.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Signed-off-by: Dave Jones <davej@redhat.com>
---
 arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
index ce7cde713e717..01bd25c3c7ca6 100644
--- a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
@@ -397,13 +397,17 @@ static int __init pcc_cpufreq_probe(void)
 	struct pcc_memory_resource *mem_resource;
 	struct pcc_register_resource *reg_resource;
 	union acpi_object *out_obj, *member;
-	acpi_handle handle, osc_handle;
+	acpi_handle handle, osc_handle, pcch_handle;
 	int ret = 0;
 
 	status = acpi_get_handle(NULL, "\\_SB", &handle);
 	if (ACPI_FAILURE(status))
 		return -ENODEV;
 
+	status = acpi_get_handle(handle, "PCCH", &pcch_handle);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
 	status = acpi_get_handle(handle, "_OSC", &osc_handle);
 	if (ACPI_SUCCESS(status)) {
 		ret = pcc_cpufreq_do_osc(&osc_handle);

From 3847d223f2e4da5ceb47ea8996618010192f3197 Mon Sep 17 00:00:00 2001
From: Daniel J Blueman <daniel.blueman@gmail.com>
Date: Fri, 23 Jul 2010 23:06:52 +0100
Subject: [PATCH 4/6] [CPUFREQ] fix double freeing in error path of pcc-cpufreq

Prevent double freeing on error path.

Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
---
 arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
index 01bd25c3c7ca6..900702888bfb9 100644
--- a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
@@ -368,22 +368,16 @@ static int __init pcc_cpufreq_do_osc(acpi_handle *handle)
 		return -ENODEV;
 
 	out_obj = output.pointer;
-	if (out_obj->type != ACPI_TYPE_BUFFER) {
-		ret = -ENODEV;
-		goto out_free;
-	}
+	if (out_obj->type != ACPI_TYPE_BUFFER)
+		return -ENODEV;
 
 	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
-	if (errors) {
-		ret = -ENODEV;
-		goto out_free;
-	}
+	if (errors)
+		return -ENODEV;
 
 	supported = *((u32 *)(out_obj->buffer.pointer + 4));
-	if (!(supported & 0x1)) {
-		ret = -ENODEV;
-		goto out_free;
-	}
+	if (!(supported & 0x1))
+		return -ENODEV;
 
 out_free:
 	kfree(output.pointer);

From 179ee43465343d1f8f2a4af25ead4ae15e43fa6e Mon Sep 17 00:00:00 2001
From: Matthew Garrett <mjg@redhat.com>
Date: Thu, 15 Jul 2010 11:44:00 -0400
Subject: [PATCH 5/6] [CPUFREQ] Fix PCC driver error path

The PCC cpufreq driver unmaps the mailbox address range if any CPUs fail to
initialise, but doesn't do anything to remove the registered CPUs from the
cpufreq core resulting in failures further down the line. We're better off
simply returning a failure - the cpufreq core will unregister us cleanly if
we end up with no successfully registered CPUs. Tidy up the failure path
and also add a sanity check to ensure that the firmware gives us a realistic
frequency - the core deals badly with that being set to 0.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Signed-off-by: Dave Jones <davej@redhat.com>
---
 arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
index 900702888bfb9..a36de5bbb6222 100644
--- a/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/pcc-cpufreq.c
@@ -541,13 +541,13 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 
 	if (!pcch_virt_addr) {
 		result = -1;
-		goto pcch_null;
+		goto out;
 	}
 
 	result = pcc_get_offset(cpu);
 	if (result) {
 		dprintk("init: PCCP evaluation failed\n");
-		goto free;
+		goto out;
 	}
 
 	policy->max = policy->cpuinfo.max_freq =
@@ -556,14 +556,15 @@ static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy)
 		ioread32(&pcch_hdr->minimum_frequency) * 1000;
 	policy->cur = pcc_get_freq(cpu);
 
+	if (!policy->cur) {
+		dprintk("init: Unable to get current CPU frequency\n");
+		result = -EINVAL;
+		goto out;
+	}
+
 	dprintk("init: policy->max is %d, policy->min is %d\n",
 		policy->max, policy->min);
-
-	return 0;
-free:
-	pcc_clear_mapping();
-	free_percpu(pcc_cpu_info);
-pcch_null:
+out:
 	return result;
 }
 

From 3581ced3b6ac289b5cd31663b34914a7347186a6 Mon Sep 17 00:00:00 2001
From: Borislav Petkov <borislav.petkov@amd.com>
Date: Thu, 8 Jul 2010 17:55:30 +0200
Subject: [PATCH 6/6] [CPUFREQ] powernow-k8: Limit Pstate transition latency
 check

The Pstate transition latency check was added for broken F10h BIOSen
which wrongly contain a value of 0 for transition and bus master
latency. Fam11h and later, however, (will) have similar transition
latency so extend that behavior for them too.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>
---
 arch/x86/kernel/cpu/cpufreq/powernow-k8.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
index 7ec2123838e6f..3e90cce3dc8bf 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
@@ -1023,13 +1023,12 @@ static int get_transition_latency(struct powernow_k8_data *data)
 	}
 	if (max_latency == 0) {
 		/*
-		 * Fam 11h always returns 0 as transition latency.
-		 * This is intended and means "very fast". While cpufreq core
-		 * and governors currently can handle that gracefully, better
-		 * set it to 1 to avoid problems in the future.
-		 * For all others it's a BIOS bug.
+		 * Fam 11h and later may return 0 as transition latency. This
+		 * is intended and means "very fast". While cpufreq core and
+		 * governors currently can handle that gracefully, better set it
+		 * to 1 to avoid problems in the future.
 		 */
-		if (boot_cpu_data.x86 != 0x11)
+		if (boot_cpu_data.x86 < 0x11)
 			printk(KERN_ERR FW_WARN PFX "Invalid zero transition "
 				"latency\n");
 		max_latency = 1;