linux-kernel - [PATCH 1/4] hotplug, x86: Fix online state in cpu0 debug interface

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 17 Aug 2013 13:46:56 -0600
From:	Toshi Kani <toshi.kani@...com>
To:	mingo@...hat.com, hpa@...ux.intel.com, tglx@...utronix.de,
	gregkh@...uxfoundation.org, benh@...nel.crashing.org
Cc:	x86@...nel.org, linuxppc-dev@...ts.ozlabs.org,
	linux-kernel@...r.kernel.org, rjw@...k.pl, fenghua.yu@...el.com,
	bp@...e.de, srivatsa.bhat@...ux.vnet.ibm.com,
	isimatu.yasuaki@...fujitsu.com, Toshi Kani <toshi.kani@...com>
Subject: [PATCH 1/4] hotplug, x86: Fix online state in cpu0 debug interface

_debug_hotplug_cpu() is a debug interface that puts cpu0 offline during
boot-up when CONFIG_DEBUG_HOTPLUG_CPU0 is set.  After cpu0 is put offline
in this interface, however, /sys/devices/system/cpu/cpu0/online still
shows 1 (online).

This patch fixes _debug_hotplug_cpu() to update dev->offline when CPU
online/offline operation succeeded.

Signed-off-by: Toshi Kani <toshi.kani@...com>
---
 arch/x86/kernel/topology.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c
index 6e60b5f..5823bbd 100644
--- a/arch/x86/kernel/topology.c
+++ b/arch/x86/kernel/topology.c
@@ -72,16 +72,19 @@ int __ref _debug_hotplug_cpu(int cpu, int action)
 		ret = cpu_down(cpu);
 		if (!ret) {
 			pr_info("CPU %u is now offline\n", cpu);
+			dev->offline = true;
 			kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
 		} else
 			pr_debug("Can't offline CPU%d.\n", cpu);
 		break;
 	case 1:
 		ret = cpu_up(cpu);
-		if (!ret)
+		if (!ret) {
+			dev->offline = false;
 			kobject_uevent(&dev->kobj, KOBJ_ONLINE);
-		else
+		} else {
 			pr_debug("Can't online CPU%d.\n", cpu);
+		}
 		break;
 	default:
 		ret = -EINVAL;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/