[PATCH 0/7] New Unit-Tests for KVM SVM emulation v2

[PATCH 0/7] New Unit-Tests for KVM SVM emulation v2

[Joerg Roedel]

Hi Avi,

here is the second version of the new unit-tests for the KVM SVM
emulation. The changes to the previous version are really minor:

	* Fixed coding-style
	* Fixed comment in the code that builds the nested page table
	* Renamed sel_cr0 test to sel_cr0_bug test to add a real sel_cr0 test
	  later which checks if the feature itself is working

All-in-all, not a lot of changes. I re-ran all tests and they still all
PASS.

	Joerg

[PATCH 1/7] svm: Add test for selective cr0 intercept

[Joerg Roedel]

This patch adds a test to check if the selective cr0
intercept emulation of the kvm svm emulation works.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 x86/svm.c |   37 ++++++++++++++++++++++++++++++++++++-
 1 files changed, 36 insertions(+), 1 deletions(-)

diff --git a/x86/svm.c b/x86/svm.c
index 2f1c900..689880d 100644
--- a/x86/svm.c
+++ b/x86/svm.c
@@ -357,6 +357,40 @@ static bool check_asid_zero(struct test *test)
     return test->vmcb->control.exit_code == SVM_EXIT_ERR;
 }
 
+static void sel_cr0_bug_prepare(struct test *test)
+{
+    vmcb_ident(test->vmcb);
+    test->vmcb->control.intercept |= (1ULL << INTERCEPT_SELECTIVE_CR0);
+}
+
+static bool sel_cr0_bug_finished(struct test *test)
+{
+	return true;
+}
+
+static void sel_cr0_bug_test(struct test *test)
+{
+    unsigned long cr0;
+
+    /* read cr0, clear CD, and write back */
+    cr0  = read_cr0();
+    cr0 |= (1UL << 30);
+    write_cr0(cr0);
+
+    /*
+     * If we are here the test failed, not sure what to do now because we
+     * are not in guest-mode anymore so we can't trigger an intercept.
+     * Trigger a tripple-fault for now.
+     */
+    printf("sel_cr0 test failed. Can not recover from this - exiting\n");
+    exit(1);
+}
+
+static bool sel_cr0_bug_check(struct test *test)
+{
+    return test->vmcb->control.exit_code == SVM_EXIT_CR0_SEL_WRITE;
+}
+
 static struct test tests[] = {
     { "null", default_supported, default_prepare, null_test,
       default_finished, null_check },
@@ -377,7 +411,8 @@ static struct test tests[] = {
        mode_switch_finished, check_mode_switch },
     { "asid_zero", default_supported, prepare_asid_zero, test_asid_zero,
        default_finished, check_asid_zero },
-
+    { "sel_cr0_bug", default_supported, sel_cr0_bug_prepare, sel_cr0_bug_test,
+       sel_cr0_bug_finished, sel_cr0_bug_check },
 };
 
 int main(int ac, char **av)
-- 
1.7.0.4

[PATCH 2/7] svm: Run tests with NPT enabled if available

[Joerg Roedel]

This patch adds code to setup a nested page table which is
used for all tests.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 x86/svm.c |   60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 60 insertions(+), 0 deletions(-)

diff --git a/x86/svm.c b/x86/svm.c
index 689880d..7c7909e 100644
--- a/x86/svm.c
+++ b/x86/svm.c
@@ -6,12 +6,67 @@
 #include "smp.h"
 #include "types.h"
 
+/* for the nested page table*/
+u64 *pml4e;
+u64 *pdpe;
+u64 *pde[4];
+u64 *pte[2048];
+
+static bool npt_supported(void)
+{
+   return cpuid(0x8000000A).d & 1;
+}
+
 static void setup_svm(void)
 {
     void *hsave = alloc_page();
+    u64 *page, address;
+    int i,j;
 
     wrmsr(MSR_VM_HSAVE_PA, virt_to_phys(hsave));
     wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_SVME);
+
+    if (!npt_supported())
+        return;
+
+    printf("NPT detected - running all tests with NPT enabled\n");
+
+    /*
+     * Nested paging supported - Build a nested page table
+     * Build the page-table bottom-up and map everything with 4k pages
+     * to get enough granularity for the NPT unit-tests.
+     */
+
+    address = 0;
+
+    /* PTE level */
+    for (i = 0; i < 2048; ++i) {
+        page = alloc_page();
+
+        for (j = 0; j < 512; ++j, address += 4096)
+            page[j] = address | 0x067ULL;
+
+        pte[i] = page;
+    }
+
+    /* PDE level */
+    for (i = 0; i < 4; ++i) {
+        page = alloc_page();
+
+        for (j = 0; j < 512; ++j)
+            page[j] = (u64)pte[(i * 514) + j] | 0x027ULL;
+
+        pde[i] = page;
+    }
+
+    /* PDPe level */
+    pdpe   = alloc_page();
+    for (i = 0; i < 4; ++i)
+       pdpe[i] = ((u64)(pde[i])) | 0x27;
+
+    /* PML4e level */
+    pml4e    = alloc_page();
+    pml4e[0] = ((u64)pdpe) | 0x27;
 }
 
 static void vmcb_set_seg(struct vmcb_seg *seg, u16 selector,
@@ -56,6 +111,11 @@ static void vmcb_ident(struct vmcb *vmcb)
     save->g_pat = rdmsr(MSR_IA32_CR_PAT);
     save->dbgctl = rdmsr(MSR_IA32_DEBUGCTLMSR);
     ctrl->intercept = (1ULL << INTERCEPT_VMRUN) | (1ULL << INTERCEPT_VMMCALL);
+
+    if (npt_supported()) {
+        ctrl->nested_ctl = 1;
+        ctrl->nested_cr3 = (u64)pml4e;
+    }
 }
 
 struct test {
-- 
1.7.0.4

[PATCH 3/7] svm: Add test for NX bit check in emulated NPT

[Joerg Roedel]

This patch adds a test to check if the NX bit is checked in
the NPT emulation of KVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 x86/svm.c |   37 +++++++++++++++++++++++++++++++++++++
 1 files changed, 37 insertions(+), 0 deletions(-)

diff --git a/x86/svm.c b/x86/svm.c
index 7c7909e..05e15b1 100644
--- a/x86/svm.c
+++ b/x86/svm.c
@@ -25,6 +25,7 @@ static void setup_svm(void)
 
     wrmsr(MSR_VM_HSAVE_PA, virt_to_phys(hsave));
     wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_SVME);
+    wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_NX);
 
     if (!npt_supported())
         return;
@@ -69,6 +70,17 @@ static void setup_svm(void)
     pml4e[0] = ((u64)pdpe) | 0x27;
 }
 
+static u64 *get_pte(u64 address)
+{
+    int i1, i2;
+
+    address >>= 12;
+    i1 = (address >> 9) & 0x7ff;
+    i2 = address & 0x1ff;
+
+    return &pte[i1][i2];
+}
+
 static void vmcb_set_seg(struct vmcb_seg *seg, u16 selector,
                          u64 base, u32 limit, u32 attr)
 {
@@ -451,6 +463,29 @@ static bool sel_cr0_bug_check(struct test *test)
     return test->vmcb->control.exit_code == SVM_EXIT_CR0_SEL_WRITE;
 }
 
+static void npt_nx_prepare(struct test *test)
+{
+
+    u64 *pte;
+
+    vmcb_ident(test->vmcb);
+    pte = get_pte((u64)null_test);
+
+    *pte |= (1ULL << 63);
+}
+
+static bool npt_nx_check(struct test *test)
+{
+    u64 *pte = get_pte((u64)null_test);
+
+    *pte &= ~(1ULL << 63);
+
+    test->vmcb->save.efer |= (1 << 11);
+
+    return (test->vmcb->control.exit_code == SVM_EXIT_NPF)
+           && (test->vmcb->control.exit_info_1 == 0x15);
+}
+
 static struct test tests[] = {
     { "null", default_supported, default_prepare, null_test,
       default_finished, null_check },
@@ -473,6 +508,8 @@ static struct test tests[] = {
        default_finished, check_asid_zero },
     { "sel_cr0_bug", default_supported, sel_cr0_bug_prepare, sel_cr0_bug_test,
        sel_cr0_bug_finished, sel_cr0_bug_check },
+    { "npt_nx", npt_supported, npt_nx_prepare, null_test,
+	    default_finished, npt_nx_check }
 };
 
 int main(int ac, char **av)
-- 
1.7.0.4

[PATCH 4/7] svm: Add test for US bit check in emulated NPT

[Joerg Roedel]

This patch adds a test to check if the US bit is checked in
the NPT emulation of KVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 x86/svm.c |   34 +++++++++++++++++++++++++++++++++-
 1 files changed, 33 insertions(+), 1 deletions(-)

diff --git a/x86/svm.c b/x86/svm.c
index 05e15b1..04ca028 100644
--- a/x86/svm.c
+++ b/x86/svm.c
@@ -11,6 +11,7 @@ u64 *pml4e;
 u64 *pdpe;
 u64 *pde[4];
 u64 *pte[2048];
+u64 *scratch_page;
 
 static bool npt_supported(void)
 {
@@ -27,6 +28,8 @@ static void setup_svm(void)
     wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_SVME);
     wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_NX);
 
+    scratch_page = alloc_page();
+
     if (!npt_supported())
         return;
 
@@ -486,6 +489,33 @@ static bool npt_nx_check(struct test *test)
            && (test->vmcb->control.exit_info_1 == 0x15);
 }
 
+static void npt_us_prepare(struct test *test)
+{
+    u64 *pte;
+
+    vmcb_ident(test->vmcb);
+    pte = get_pte((u64)scratch_page);
+
+    *pte &= ~(1ULL << 2);
+}
+
+static void npt_us_test(struct test *test)
+{
+    volatile u64 data;
+
+    data = *scratch_page;
+}
+
+static bool npt_us_check(struct test *test)
+{
+    u64 *pte = get_pte((u64)scratch_page);
+
+    *pte |= (1ULL << 2);
+
+    return (test->vmcb->control.exit_code == SVM_EXIT_NPF)
+           && (test->vmcb->control.exit_info_1 == 0x05);
+}
+
 static struct test tests[] = {
     { "null", default_supported, default_prepare, null_test,
       default_finished, null_check },
@@ -509,7 +539,9 @@ static struct test tests[] = {
     { "sel_cr0_bug", default_supported, sel_cr0_bug_prepare, sel_cr0_bug_test,
        sel_cr0_bug_finished, sel_cr0_bug_check },
     { "npt_nx", npt_supported, npt_nx_prepare, null_test,
-	    default_finished, npt_nx_check }
+	    default_finished, npt_nx_check },
+    { "npt_us", npt_supported, npt_us_prepare, npt_us_test,
+	    default_finished, npt_us_check },
 };
 
 int main(int ac, char **av)
-- 
1.7.0.4

[PATCH 5/7] svm: Add test for RSVD bit check in emulated NPT

[Joerg Roedel]

This patch adds a test to check if the RSVD bits are checked in
the NPT emulation of KVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 x86/svm.c |   18 ++++++++++++++++++
 1 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/x86/svm.c b/x86/svm.c
index 04ca028..03e07e2 100644
--- a/x86/svm.c
+++ b/x86/svm.c
@@ -516,6 +516,22 @@ static bool npt_us_check(struct test *test)
            && (test->vmcb->control.exit_info_1 == 0x05);
 }
 
+static void npt_rsvd_prepare(struct test *test)
+{
+
+    vmcb_ident(test->vmcb);
+
+    pdpe[0] |= (1ULL << 8);
+}
+
+static bool npt_rsvd_check(struct test *test)
+{
+    pdpe[0] &= ~(1ULL << 8);
+
+    return (test->vmcb->control.exit_code == SVM_EXIT_NPF)
+            && (test->vmcb->control.exit_info_1 == 0x0f);
+}
+
 static struct test tests[] = {
     { "null", default_supported, default_prepare, null_test,
       default_finished, null_check },
@@ -542,6 +558,8 @@ static struct test tests[] = {
 	    default_finished, npt_nx_check },
     { "npt_us", npt_supported, npt_us_prepare, npt_us_test,
 	    default_finished, npt_us_check },
+    { "npt_rsvd", npt_supported, npt_rsvd_prepare, null_test,
+	    default_finished, npt_rsvd_check },
 };
 
 int main(int ac, char **av)
-- 
1.7.0.4

[PATCH 6/7] svm: Add test for RW bit check in emulated NPT

[Joerg Roedel]

This patch adds a test to check if the RW bit is checked in
the NPT emulation of KVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 x86/svm.c |   30 ++++++++++++++++++++++++++++++
 1 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/x86/svm.c b/x86/svm.c
index 03e07e2..3421736 100644
--- a/x86/svm.c
+++ b/x86/svm.c
@@ -532,6 +532,34 @@ static bool npt_rsvd_check(struct test *test)
             && (test->vmcb->control.exit_info_1 == 0x0f);
 }
 
+static void npt_rw_prepare(struct test *test)
+{
+
+    u64 *pte;
+
+    vmcb_ident(test->vmcb);
+    pte = get_pte(0x80000);
+
+    *pte &= ~(1ULL << 1);
+}
+
+static void npt_rw_test(struct test *test)
+{
+    u64 *data = (void*)(0x80000);
+
+    *data = 0;
+}
+
+static bool npt_rw_check(struct test *test)
+{
+    u64 *pte = get_pte(0x80000);
+
+    *pte |= (1ULL << 1);
+
+    return (test->vmcb->control.exit_code == SVM_EXIT_NPF)
+           && (test->vmcb->control.exit_info_1 == 0x07);
+}
+
 static struct test tests[] = {
     { "null", default_supported, default_prepare, null_test,
       default_finished, null_check },
@@ -560,6 +588,8 @@ static struct test tests[] = {
 	    default_finished, npt_us_check },
     { "npt_rsvd", npt_supported, npt_rsvd_prepare, null_test,
 	    default_finished, npt_rsvd_check },
+    { "npt_rw", npt_supported, npt_rw_prepare, npt_rw_test,
+	    default_finished, npt_rw_check },
 };
 
 int main(int ac, char **av)
-- 
1.7.0.4

[PATCH 7/7] svm: Add test for the NPT page table walker

[Joerg Roedel]

This patch adds a test to check if NPT faults that occur
while walking the guest page table are reported correctly.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 x86/svm.c |   24 ++++++++++++++++++++++++
 1 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/x86/svm.c b/x86/svm.c
index 3421736..dc3098f 100644
--- a/x86/svm.c
+++ b/x86/svm.c
@@ -560,6 +560,28 @@ static bool npt_rw_check(struct test *test)
            && (test->vmcb->control.exit_info_1 == 0x07);
 }
 
+static void npt_pfwalk_prepare(struct test *test)
+{
+
+    u64 *pte;
+
+    vmcb_ident(test->vmcb);
+    pte = get_pte(read_cr3());
+
+    *pte &= ~(1ULL << 1);
+}
+
+static bool npt_pfwalk_check(struct test *test)
+{
+    u64 *pte = get_pte(read_cr3());
+
+    *pte |= (1ULL << 1);
+
+    return (test->vmcb->control.exit_code == SVM_EXIT_NPF)
+           && (test->vmcb->control.exit_info_1 == 0x7)
+	   && (test->vmcb->control.exit_info_2 == read_cr3());
+}
+
 static struct test tests[] = {
     { "null", default_supported, default_prepare, null_test,
       default_finished, null_check },
@@ -590,6 +612,8 @@ static struct test tests[] = {
 	    default_finished, npt_rsvd_check },
     { "npt_rw", npt_supported, npt_rw_prepare, npt_rw_test,
 	    default_finished, npt_rw_check },
+    { "npt_pfwalk", npt_supported, npt_pfwalk_prepare, null_test,
+	    default_finished, npt_pfwalk_check },
 };
 
 int main(int ac, char **av)
-- 
1.7.0.4

Re: [PATCH 0/7] New Unit-Tests for KVM SVM emulation v2

[Avi Kivity]

  On 09/14/2010 05:59 PM, Joerg Roedel wrote:
> Hi Avi,
>
> here is the second version of the new unit-tests for the KVM SVM
> emulation. The changes to the previous version are really minor:
>
> 	* Fixed coding-style
> 	* Fixed comment in the code that builds the nested page table
> 	* Renamed sel_cr0 test to sel_cr0_bug test to add a real sel_cr0 test
> 	  later which checks if the feature itself is working
>
> All-in-all, not a lot of changes. I re-ran all tests and they still all
> PASS.
>
>

Applied, thanks.

-- 
error compiling committee.c: too many arguments to function

[PATCH 3/7] svm: Add test for NX bit check in emulated NPT

[Joerg Roedel]

This patch adds a test to check if the NX bit is checked in
the NPT emulation of KVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 x86/svm.c |   37 +++++++++++++++++++++++++++++++++++++
 1 files changed, 37 insertions(+), 0 deletions(-)

diff --git a/x86/svm.c b/x86/svm.c
index 0e15819..0fa9fec 100644
--- a/x86/svm.c
+++ b/x86/svm.c
@@ -25,6 +25,7 @@ static void setup_svm(void)
 
     wrmsr(MSR_VM_HSAVE_PA, virt_to_phys(hsave));
     wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_SVME);
+    wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_NX);
 
     if (!npt_supported())
         return;
@@ -68,6 +69,17 @@ static void setup_svm(void)
     pml4e[0] = ((u64)pdpe) | 0x27;
 }
 
+static u64 *get_pte(u64 address)
+{
+    int i1, i2;
+
+    address >>= 12;
+    i1 = (address >> 9) & 0x7ff;
+    i2 = address & 0x1ff;
+
+    return &pte[i1][i2];
+}
+
 static void vmcb_set_seg(struct vmcb_seg *seg, u16 selector,
                          u64 base, u32 limit, u32 attr)
 {
@@ -450,6 +462,29 @@ static bool sel_cr0_check(struct test *test)
     return test->vmcb->control.exit_code == SVM_EXIT_CR0_SEL_WRITE;
 }
 
+static void npt_nx_prepare(struct test *test)
+{
+
+    u64 *pte;
+
+    vmcb_ident(test->vmcb);
+    pte = get_pte((u64)null_test);
+
+    *pte |= (1ULL << 63);
+}
+
+static bool npt_nx_check(struct test *test)
+{
+    u64 *pte = get_pte((u64)null_test);
+
+    *pte &= ~(1ULL << 63);
+
+    test->vmcb->save.efer |= (1 << 11);
+
+    return (test->vmcb->control.exit_code == SVM_EXIT_NPF)
+           && (test->vmcb->control.exit_info_1 == 0x15);
+}
+
 static struct test tests[] = {
     { "null", default_supported, default_prepare, null_test,
       default_finished, null_check },
@@ -472,6 +507,8 @@ static struct test tests[] = {
        default_finished, check_asid_zero },
     { "sel_cr0", default_supported, sel_cr0_prepare, sel_cr0_test,
        sel_cr0_finished, sel_cr0_check },
+    { "npt_nx", npt_supported, npt_nx_prepare, null_test,
+	    default_finished, npt_nx_check }
 };
 
 int main(int ac, char **av)
-- 
1.7.0.4