lkml.org 
[lkml]   [2022]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 30/30] RFC: KVM: Remove cpus_hardware_enabled and related sanity check
Date
From: Isaku Yamahata <isaku.yamahata@intel.com>

cpus_hardware_enabled mask seems incomplete protection against other kernel
component using CPU virtualization feature. Because it's obscure and
incomplete, remove the check.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
virt/kvm/kvm_arch.c | 15 +--------------
1 file changed, 1 insertion(+), 14 deletions(-)

diff --git a/virt/kvm/kvm_arch.c b/virt/kvm/kvm_arch.c
index 076a55d59988..e7708bfa0360 100644
--- a/virt/kvm/kvm_arch.c
+++ b/virt/kvm/kvm_arch.c
@@ -12,23 +12,16 @@

#include <linux/kvm_host.h>

-static cpumask_t cpus_hardware_enabled = CPU_MASK_NONE;
-
static int __hardware_enable(void)
{
- int cpu = raw_smp_processor_id();
int r;

WARN_ON_ONCE(preemptible());

- if (cpumask_test_cpu(cpu, &cpus_hardware_enabled))
- return 0;
r = kvm_arch_hardware_enable();
if (r)
pr_warn("kvm: enabling virtualization on CPU%d failed during %pSb\n",
- cpu, __builtin_return_address(0));
- else
- cpumask_set_cpu(cpu, &cpus_hardware_enabled);
+ smp_processor_id(), __builtin_return_address(0));
return r;
}

@@ -42,13 +35,7 @@ static void hardware_enable(void *arg)

static void hardware_disable(void *junk)
{
- int cpu = raw_smp_processor_id();
-
WARN_ON_ONCE(preemptible());
-
- if (!cpumask_test_cpu(cpu, &cpus_hardware_enabled))
- return;
- cpumask_clear_cpu(cpu, &cpus_hardware_enabled);
kvm_arch_hardware_disable();
}

--
2.25.1
\
 
 \ /
  Last update: 2022-09-22 20:26    [W:0.275 / U:0.388 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site