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From: Dongxiao Xu <dongxiao.xu@intel.com>
To: xen-devel@lists.xen.org
Subject: [PATCH 01/10] nested vmx: emulate MSR bitmaps
Date: Tue,  4 Dec 2012 13:53:21 +0800	[thread overview]
Message-ID: <1354600410-3390-2-git-send-email-dongxiao.xu@intel.com> (raw)
In-Reply-To: <1354600410-3390-1-git-send-email-dongxiao.xu@intel.com>

In nested vmx virtualization for MSR bitmaps, L0 hypervisor will trap all the VM
exit from L2 guest by disable the MSR_BITMAP feature. When handling this VM exit,
L0 hypervisor judges whether L1 hypervisor uses MSR_BITMAP feature and the
corresponding bit is set to 1. If so, L0 will inject such VM exit into L1
hypervisor; otherwise, L0 will be responsible for handling this VM exit.

Signed-off-by: Dongxiao Xu <dongxiao.xu@intel.com>
---
 xen/arch/x86/hvm/vmx/vmcs.c        |   28 +++++++++++++++++++++++++
 xen/arch/x86/hvm/vmx/vvmx.c        |   39 ++++++++++++++++++++++++++++++++++-
 xen/include/asm-x86/hvm/vmx/vmcs.h |    1 +
 xen/include/asm-x86/hvm/vmx/vvmx.h |    1 +
 4 files changed, 67 insertions(+), 2 deletions(-)

diff --git a/xen/arch/x86/hvm/vmx/vmcs.c b/xen/arch/x86/hvm/vmx/vmcs.c
index 0fbdd75..205e705 100644
--- a/xen/arch/x86/hvm/vmx/vmcs.c
+++ b/xen/arch/x86/hvm/vmx/vmcs.c
@@ -674,6 +674,34 @@ void vmx_disable_intercept_for_msr(struct vcpu *v, u32 msr, int type)
 }
 
 /*
+ * access_type: read == 0, write == 1
+ */
+int vmx_check_msr_bitmap(unsigned long *msr_bitmap, u32 msr, int access_type)
+{
+    int ret = 1;
+    if ( !msr_bitmap )
+        return 1;
+
+    if ( msr <= 0x1fff )
+    {
+        if ( access_type == 0 )
+            ret = test_bit(msr, msr_bitmap + 0x000/BYTES_PER_LONG); /* read-low */
+        else if ( access_type == 1 )
+            ret = test_bit(msr, msr_bitmap + 0x800/BYTES_PER_LONG); /* write-low */
+    }
+    else if ( (msr >= 0xc0000000) && (msr <= 0xc0001fff) )
+    {
+        msr &= 0x1fff;
+        if ( access_type == 0 )
+            ret = test_bit(msr, msr_bitmap + 0x400/BYTES_PER_LONG); /* read-high */
+        else if ( access_type == 1 )
+            ret = test_bit(msr, msr_bitmap + 0xc00/BYTES_PER_LONG); /* write-high */
+    }
+    return ret;
+}
+
+
+/*
  * Switch VMCS between layer 1 & 2 guest
  */
 void vmx_vmcs_switch(struct vmcs_struct *from, struct vmcs_struct *to)
diff --git a/xen/arch/x86/hvm/vmx/vvmx.c b/xen/arch/x86/hvm/vmx/vvmx.c
index ed47780..719bfce 100644
--- a/xen/arch/x86/hvm/vmx/vvmx.c
+++ b/xen/arch/x86/hvm/vmx/vvmx.c
@@ -48,6 +48,7 @@ int nvmx_vcpu_initialise(struct vcpu *v)
     nvmx->intr.error_code = 0;
     nvmx->iobitmap[0] = NULL;
     nvmx->iobitmap[1] = NULL;
+    nvmx->msrbitmap = NULL;
     return 0;
 out:
     return -ENOMEM;
@@ -561,6 +562,17 @@ static void __clear_current_vvmcs(struct vcpu *v)
         __vmpclear(virt_to_maddr(nvcpu->nv_n2vmcx));
 }
 
+static void __map_msr_bitmap(struct vcpu *v)
+{
+    struct nestedvmx *nvmx = &vcpu_2_nvmx(v);
+    unsigned long gpa;
+
+    if ( nvmx->msrbitmap )
+        hvm_unmap_guest_frame (nvmx->msrbitmap); 
+    gpa = __get_vvmcs(vcpu_nestedhvm(v).nv_vvmcx, MSR_BITMAP);
+    nvmx->msrbitmap = hvm_map_guest_frame_ro(gpa >> PAGE_SHIFT);
+}
+
 static void __map_io_bitmap(struct vcpu *v, u64 vmcs_reg)
 {
     struct nestedvmx *nvmx = &vcpu_2_nvmx(v);
@@ -597,6 +609,10 @@ static void nvmx_purge_vvmcs(struct vcpu *v)
             nvmx->iobitmap[i] = NULL;
         }
     }
+    if ( nvmx->msrbitmap ) {
+        hvm_unmap_guest_frame(nvmx->msrbitmap);
+        nvmx->msrbitmap = NULL;
+    }
 }
 
 u64 nvmx_get_tsc_offset(struct vcpu *v)
@@ -1153,6 +1169,7 @@ int nvmx_handle_vmptrld(struct cpu_user_regs *regs)
         nvcpu->nv_vvmcx = hvm_map_guest_frame_rw(gpa >> PAGE_SHIFT);
         nvcpu->nv_vvmcxaddr = gpa;
         map_io_bitmap_all (v);
+        __map_msr_bitmap(v);
     }
 
     vmreturn(regs, VMSUCCEED);
@@ -1270,6 +1287,9 @@ int nvmx_handle_vmwrite(struct cpu_user_regs *regs)
               vmcs_encoding == IO_BITMAP_B_HIGH )
         __map_io_bitmap (v, IO_BITMAP_B);
 
+    if ( vmcs_encoding == MSR_BITMAP || vmcs_encoding == MSR_BITMAP_HIGH )
+        __map_msr_bitmap(v);
+
     vmreturn(regs, VMSUCCEED);
     return X86EMUL_OKAY;
 }
@@ -1320,6 +1340,7 @@ int nvmx_msr_read_intercept(unsigned int msr, u64 *msr_content)
                CPU_BASED_RDTSC_EXITING |
                CPU_BASED_MONITOR_TRAP_FLAG |
                CPU_BASED_VIRTUAL_NMI_PENDING |
+               CPU_BASED_ACTIVATE_MSR_BITMAP |
                CPU_BASED_ACTIVATE_SECONDARY_CONTROLS;
         /* bit 1, 4-6,8,13-16,26 must be 1 (refer G4 of SDM) */
         tmp = ( (1<<26) | (0xf << 13) | 0x100 | (0x7 << 4) | 0x2);
@@ -1497,8 +1518,6 @@ int nvmx_n2_vmexit_handler(struct cpu_user_regs *regs,
     case EXIT_REASON_TRIPLE_FAULT:
     case EXIT_REASON_TASK_SWITCH:
     case EXIT_REASON_CPUID:
-    case EXIT_REASON_MSR_READ:
-    case EXIT_REASON_MSR_WRITE:
     case EXIT_REASON_VMCALL:
     case EXIT_REASON_VMCLEAR:
     case EXIT_REASON_VMLAUNCH:
@@ -1514,6 +1533,22 @@ int nvmx_n2_vmexit_handler(struct cpu_user_regs *regs,
         /* inject to L1 */
         nvcpu->nv_vmexit_pending = 1;
         break;
+    case EXIT_REASON_MSR_READ:
+    case EXIT_REASON_MSR_WRITE:
+    {
+        int status;
+        ctrl = __n2_exec_control(v);
+        if ( ctrl & CPU_BASED_ACTIVATE_MSR_BITMAP )
+        {
+            status = vmx_check_msr_bitmap(nvmx->msrbitmap, regs->ecx,
+                         !!(exit_reason == EXIT_REASON_MSR_WRITE));
+            if ( status )
+                nvcpu->nv_vmexit_pending = 1;
+        }
+        else
+            nvcpu->nv_vmexit_pending = 1;
+        break;
+    }
     case EXIT_REASON_IO_INSTRUCTION:
         ctrl = __n2_exec_control(v);
         if ( ctrl & CPU_BASED_ACTIVATE_IO_BITMAP )
diff --git a/xen/include/asm-x86/hvm/vmx/vmcs.h b/xen/include/asm-x86/hvm/vmx/vmcs.h
index cc92f69..14ac773 100644
--- a/xen/include/asm-x86/hvm/vmx/vmcs.h
+++ b/xen/include/asm-x86/hvm/vmx/vmcs.h
@@ -427,6 +427,7 @@ int vmx_add_host_load_msr(u32 msr);
 void vmx_vmcs_switch(struct vmcs_struct *from, struct vmcs_struct *to);
 void vmx_set_eoi_exit_bitmap(struct vcpu *v, u8 vector);
 void vmx_clear_eoi_exit_bitmap(struct vcpu *v, u8 vector);
+int vmx_check_msr_bitmap(unsigned long *msr_bitmap, u32 msr, int access_type);
 
 #endif /* ASM_X86_HVM_VMX_VMCS_H__ */
 
diff --git a/xen/include/asm-x86/hvm/vmx/vvmx.h b/xen/include/asm-x86/hvm/vmx/vvmx.h
index b9137b8..067fbe4 100644
--- a/xen/include/asm-x86/hvm/vmx/vvmx.h
+++ b/xen/include/asm-x86/hvm/vmx/vvmx.h
@@ -26,6 +26,7 @@
 struct nestedvmx {
     paddr_t    vmxon_region_pa;
     void       *iobitmap[2];		/* map (va) of L1 guest I/O bitmap */
+    void       *msrbitmap;		/* map (va) of L1 guest MSR bitmap */
     /* deferred nested interrupt */
     struct {
         unsigned long intr_info;
-- 
1.7.1

  reply	other threads:[~2012-12-04  5:53 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-12-04  5:53 [PATCH 00/10] nested vmx: bug fixes and feature enabling Dongxiao Xu
2012-12-04  5:53 ` Dongxiao Xu [this message]
2012-12-04  5:53 ` [PATCH 02/10] nested vmx: expose bit 55 of IA32_VMX_BASIC_MSR to guest VMM Dongxiao Xu
2012-12-04  9:59   ` Jan Beulich
2012-12-05  1:35     ` Xu, Dongxiao
2012-12-04  5:53 ` [PATCH 03/10] nested vmx: fix rflags status in virtual vmexit Dongxiao Xu
2012-12-04  5:53 ` [PATCH 04/10] nested vmx: fix handling of RDTSC Dongxiao Xu
2012-12-04  5:53 ` [PATCH 05/10] nested vmx: fix DR access VM exit Dongxiao Xu
2012-12-04 10:02   ` Jan Beulich
2012-12-05  1:27     ` Xu, Dongxiao
2012-12-04  5:53 ` [PATCH 06/10] nested vmx: enable IA32E mode while do VM entry Dongxiao Xu
2012-12-04 10:03   ` Jan Beulich
2012-12-05  1:26     ` Xu, Dongxiao
2012-12-04  5:53 ` [PATCH 07/10] nested vmx: enable "Virtualize APIC accesses" feature for L1 VMM Dongxiao Xu
2012-12-04  5:53 ` [PATCH 08/10] nested vmx: enable PAUSE and RDPMC exiting " Dongxiao Xu
2012-12-04  5:53 ` [PATCH 09/10] nested vmx: fix interrupt delivery to L2 guest Dongxiao Xu
2012-12-04  5:53 ` [PATCH 10/10] nested vmx: check host ability when intercept MSR read Dongxiao Xu
2012-12-04 10:05 ` [PATCH 00/10] nested vmx: bug fixes and feature enabling Jan Beulich
2012-12-05  1:37   ` Xu, Dongxiao

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