[PATCH v4 2/2] KVM: set/unset crash_clear_loaded_vmcss and vmclear_skippedin kvm_intel module

From: zhangyanfei
Date: Wed Nov 14 2012 - 04:33:47 EST


Signed-off-by: Zhang Yanfei <zhangyanfei@xxxxxxxxxxxxxx>
---
arch/x86/kvm/vmx.c | 32 ++++++++++++++++++++++++++++++++
1 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 4ff0ab9..029ec7b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -41,6 +41,7 @@
#include <asm/i387.h>
#include <asm/xcr.h>
#include <asm/perf_event.h>
+#include <asm/kexec.h>

#include "trace.h"

@@ -963,6 +964,20 @@ static void vmcs_load(struct vmcs *vmcs)
vmcs, phys_addr);
}

+static inline void enable_vmclear_in_kdump(int cpu)
+{
+#ifdef CONFIG_KEXEC
+ per_cpu(vmclear_skipped, cpu) = 0;
+#endif
+}
+
+static inline void disable_vmclear_in_kdump(int cpu)
+{
+#ifdef CONFIG_KEXEC
+ per_cpu(vmclear_skipped, cpu) = 1;
+#endif
+}
+
static void __loaded_vmcs_clear(void *arg)
{
struct loaded_vmcs *loaded_vmcs = arg;
@@ -972,8 +987,10 @@ static void __loaded_vmcs_clear(void *arg)
return; /* vcpu migration can race with cpu offline */
if (per_cpu(current_vmcs, cpu) == loaded_vmcs->vmcs)
per_cpu(current_vmcs, cpu) = NULL;
+ disable_vmclear_in_kdump(cpu);
list_del(&loaded_vmcs->loaded_vmcss_on_cpu_link);
loaded_vmcs_init(loaded_vmcs);
+ enable_vmclear_in_kdump(cpu);
}

static void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs)
@@ -1491,8 +1508,10 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)

kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
local_irq_disable();
+ disable_vmclear_in_kdump(cpu);
list_add(&vmx->loaded_vmcs->loaded_vmcss_on_cpu_link,
&per_cpu(loaded_vmcss_on_cpu, cpu));
+ enable_vmclear_in_kdump(cpu);
local_irq_enable();

/*
@@ -2302,6 +2321,9 @@ static int hardware_enable(void *garbage)
return -EBUSY;

INIT_LIST_HEAD(&per_cpu(loaded_vmcss_on_cpu, cpu));
+
+ enable_vmclear_in_kdump(cpu);
+
rdmsrl(MSR_IA32_FEATURE_CONTROL, old);

test_bits = FEATURE_CONTROL_LOCKED;
@@ -2333,6 +2355,8 @@ static void vmclear_local_loaded_vmcss(void)
list_for_each_entry_safe(v, n, &per_cpu(loaded_vmcss_on_cpu, cpu),
loaded_vmcss_on_cpu_link)
__loaded_vmcs_clear(v);
+
+ disable_vmclear_in_kdump(cpu);
}


@@ -7230,6 +7254,10 @@ static int __init vmx_init(void)
if (r)
goto out3;

+#ifdef CONFIG_KEXEC
+ crash_clear_loaded_vmcss = vmclear_local_loaded_vmcss;
+#endif
+
vmx_disable_intercept_for_msr(MSR_FS_BASE, false);
vmx_disable_intercept_for_msr(MSR_GS_BASE, false);
vmx_disable_intercept_for_msr(MSR_KERNEL_GS_BASE, true);
@@ -7265,6 +7293,10 @@ static void __exit vmx_exit(void)
free_page((unsigned long)vmx_io_bitmap_b);
free_page((unsigned long)vmx_io_bitmap_a);

+#ifdef CONFIG_KEXEC
+ crash_clear_loaded_vmcss = NULL;
+#endif
+
kvm_exit();
}

--
1.7.1
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