| Message ID | 20210520211708.70069-1-krish.sadhukhan@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | nSVM: Test: Test VMRUN's canonicalization of segement base addresses | expand |
On Thu, May 20, 2021 at 3:06 PM Krish Sadhukhan <krish.sadhukhan@oracle.com> wrote: > > According to section "Canonicalization and Consistency Checks" in APM vol 2, > > VMRUN canonicalizes (i.e., sign-extend to bit 63) all base addresses > in the segment registers that have been loaded. > > Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> > --- > x86/svm_tests.c | 29 +++++++++++++++++++++++++++++ > 1 file changed, 29 insertions(+) > > diff --git a/x86/svm_tests.c b/x86/svm_tests.c > index d689e73..8387bea 100644 > --- a/x86/svm_tests.c > +++ b/x86/svm_tests.c > @@ -2499,6 +2499,34 @@ static void test_msrpm_iopm_bitmap_addrs(void) > vmcb->control.intercept = saved_intercept; > } > > +#define TEST_CANONICAL(seg_base, msg) \ > + saved_addr = seg_base; \ > + seg_base = (seg_base & ((1ul << addr_limit) - 1)) | noncanonical_mask; \ > + report(svm_vmrun() == SVM_EXIT_VMMCALL, "Test %s.base for canonical form: %lx", msg, seg_base); \ > + seg_base = saved_addr; This is messy. Why not just set seg_base to NONCANONICAL before svm_vmrun() and then check to see that it's equal to canonicalize(NONCANONICAL) after #VMEXIT? > +/* > + * VMRUN canonicalizes (i.e., sign-extend to bit 63) all base addresses > + • in the segment registers that have been loaded. > + */ > +static void test_vmrun_canonicalization(void) > +{ > + u64 saved_addr; > + u8 addr_limit = cpuid_maxphyaddr(); What constitutes a canonical address depends on the maximum *virtual* address width supported, not the maximum physical address width supported. > + u64 noncanonical_mask = NONCANONICAL & ~((1ul << addr_limit) - 1); > + > + TEST_CANONICAL(vmcb->save.es.base, "ES"); > + TEST_CANONICAL(vmcb->save.cs.base, "CS"); > + TEST_CANONICAL(vmcb->save.ss.base, "SS"); > + TEST_CANONICAL(vmcb->save.ds.base, "DS"); > + TEST_CANONICAL(vmcb->save.fs.base, "FS"); > + TEST_CANONICAL(vmcb->save.gs.base, "GS"); > + TEST_CANONICAL(vmcb->save.gdtr.base, "GDTR"); > + TEST_CANONICAL(vmcb->save.ldtr.base, "LDTR"); > + TEST_CANONICAL(vmcb->save.idtr.base, "IDTR"); > + TEST_CANONICAL(vmcb->save.tr.base, "TR"); There are only 8 segment registers. GDTR and IDTR are not segment registers. They may be canonicalized by VMRUN/#VMEXIT, but they are not segment registers. > +} > + > static void svm_guest_state_test(void) > { > test_set_guest(basic_guest_main); > @@ -2508,6 +2536,7 @@ static void svm_guest_state_test(void) > test_cr4(); > test_dr(); > test_msrpm_iopm_bitmap_addrs(); > + test_vmrun_canonicalization(); > } > > > -- > 2.27.0 >
diff --git a/x86/svm_tests.c b/x86/svm_tests.c index d689e73..8387bea 100644 --- a/x86/svm_tests.c +++ b/x86/svm_tests.c @@ -2499,6 +2499,34 @@ static void test_msrpm_iopm_bitmap_addrs(void) vmcb->control.intercept = saved_intercept; } +#define TEST_CANONICAL(seg_base, msg) \ + saved_addr = seg_base; \ + seg_base = (seg_base & ((1ul << addr_limit) - 1)) | noncanonical_mask; \ + report(svm_vmrun() == SVM_EXIT_VMMCALL, "Test %s.base for canonical form: %lx", msg, seg_base); \ + seg_base = saved_addr; + +/* + * VMRUN canonicalizes (i.e., sign-extend to bit 63) all base addresses + • in the segment registers that have been loaded. + */ +static void test_vmrun_canonicalization(void) +{ + u64 saved_addr; + u8 addr_limit = cpuid_maxphyaddr(); + u64 noncanonical_mask = NONCANONICAL & ~((1ul << addr_limit) - 1); + + TEST_CANONICAL(vmcb->save.es.base, "ES"); + TEST_CANONICAL(vmcb->save.cs.base, "CS"); + TEST_CANONICAL(vmcb->save.ss.base, "SS"); + TEST_CANONICAL(vmcb->save.ds.base, "DS"); + TEST_CANONICAL(vmcb->save.fs.base, "FS"); + TEST_CANONICAL(vmcb->save.gs.base, "GS"); + TEST_CANONICAL(vmcb->save.gdtr.base, "GDTR"); + TEST_CANONICAL(vmcb->save.ldtr.base, "LDTR"); + TEST_CANONICAL(vmcb->save.idtr.base, "IDTR"); + TEST_CANONICAL(vmcb->save.tr.base, "TR"); +} + static void svm_guest_state_test(void) { test_set_guest(basic_guest_main); @@ -2508,6 +2536,7 @@ static void svm_guest_state_test(void) test_cr4(); test_dr(); test_msrpm_iopm_bitmap_addrs(); + test_vmrun_canonicalization(); }
According to section "Canonicalization and Consistency Checks" in APM vol 2, VMRUN canonicalizes (i.e., sign-extend to bit 63) all base addresses in the segment registers that have been loaded. Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> --- x86/svm_tests.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+)