Skip to contentSkip to conversation

Patch "ACPI: CPPC: Return error if _CPC is invalid on a CPU" has been added to the 4.7-stable tree

PATCH [email protected] 1 participant 1 message Sep 2, 2016

Subsystems (3)
lore
Share & tools
lore

[email protected]

author maintainer Applied
#0 lore raw

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

ACPI: CPPC: Return error if _CPC is invalid on a CPU

to the 4.7-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-cppc-return-error-if-_cpc-is-invalid-on-a-cpu.patch
and it can be found in the queue-4.7 subdirectory.

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

Quoted 1 line

From 8343c40d3de32ebfe8f48b043964e4ba0e7701f7 Mon Sep 17 00:00:00 2001

From: Hoan Tran <[email protected]>
Date: Fri, 17 Jun 2016 15:16:31 -0700
Subject: ACPI: CPPC: Return error if _CPC is invalid on a CPU

From: Hoan Tran <[email protected]>

commit 8343c40d3de32ebfe8f48b043964e4ba0e7701f7 upstream.

Based on 8.4.7.1 section of ACPI 6.1 specification, if the platform supports CPPC, the _CPC object must exist under all processor objects. If cpc_desc_ptr pointer is invalid on any CPUs, acpi_get_psd_map() should return error and CPPC cpufreq driver can not be registered.

---
 drivers/acpi/cppc_acpi.c |   18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)
drivers/acpi/cppc_acpi.c +12 -6
@@ -299,8 +299,10 @@ int acpi_get_psd_map(struct cpudata **al
 			continue;
 
 		cpc_ptr = per_cpu(cpc_desc_ptr, i);
-		if (!cpc_ptr)
-			continue;
+		if (!cpc_ptr) {
+			retval = -EFAULT;
+			goto err_ret;
+		}
 
 		pdomain = &(cpc_ptr->domain_info);
 		cpumask_set_cpu(i, pr->shared_cpu_map);
@@ -322,8 +324,10 @@ int acpi_get_psd_map(struct cpudata **al
 				continue;
 
 			match_cpc_ptr = per_cpu(cpc_desc_ptr, j);
-			if (!match_cpc_ptr)
-				continue;
+			if (!match_cpc_ptr) {
+				retval = -EFAULT;
+				goto err_ret;
+			}
 
 			match_pdomain = &(match_cpc_ptr->domain_info);
 			if (match_pdomain->domain != pdomain->domain)
@@ -353,8 +357,10 @@ int acpi_get_psd_map(struct cpudata **al
 				continue;
 
 			match_cpc_ptr = per_cpu(cpc_desc_ptr, j);
-			if (!match_cpc_ptr)
-				continue;
+			if (!match_cpc_ptr) {
+				retval = -EFAULT;
+				goto err_ret;
+			}
 
 			match_pdomain = &(match_cpc_ptr->domain_info);
 			if (match_pdomain->domain != pdomain->domain)

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

queue-4.7/acpi-cppc-return-error-if-_cpc-is-invalid-on-a-cpu.patch queue-4.7/acpi-cppc-prevent-cpc_desc_ptr-points-to-the-invalid-data.patch