[xen master] x86/svm: Provide EXITINFO decodes for Exceptions/NPF intercepts

[patchbot@xxxxxxx]

commit ddaf7bb0cfd27369252de52e4b03410c4065bad2
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Fri Mar 17 11:10:06 2023 +0000
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Thu Apr 6 15:39:12 2023 +0100

    x86/svm: Provide EXITINFO decodes for Exceptions/NPF intercepts
    
    Exceptions and NPF intercepts almost have the same layout, but NPF has bits
    above 31 in the error code, and the name for exitinfo2 really does want
    distinguishing between cr2 and gpa.
    
    In nsvm_vcpu_vmexit_inject() rearrange VMEXIT_NPF to fall through instead of
    repeating the exitinfo1 write.  Use the fallthrough pseudo keyword instead 
of
    a comment.
    
    In VMEXIT_NPF, as we're editing the printk() anyway, switch to using the 
newer
    domain_crash() form.
    
    No functional change.
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/arch/x86/hvm/svm/nestedsvm.c        |  9 +++------
 xen/arch/x86/hvm/svm/svm.c              | 23 ++++++++++-------------
 xen/arch/x86/include/asm/hvm/svm/vmcb.h | 10 ++++++++++
 3 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/xen/arch/x86/hvm/svm/nestedsvm.c b/xen/arch/x86/hvm/svm/nestedsvm.c
index 2003f28f66..51e437e73a 100644
--- a/xen/arch/x86/hvm/svm/nestedsvm.c
+++ b/xen/arch/x86/hvm/svm/nestedsvm.c
@@ -824,14 +824,11 @@ nsvm_vcpu_vmexit_inject(struct vcpu *v, struct 
cpu_user_regs *regs,
                 ns_vmcb->exit_int_info = ns_vmcb->event_inj;
             break;
         case VMEXIT_EXCEPTION_PF:
-            ns_vmcb->_cr2 = ns_vmcb->exitinfo2;
-            /* fall through */
+            ns_vmcb->_cr2 = ns_vmcb->ei.exc.cr2;
+            fallthrough;
         case VMEXIT_NPF:
-            /* PF error code */
-            ns_vmcb->exitinfo1 = svm->ns_vmexit.exitinfo1;
-            /* fault address */
             ns_vmcb->exitinfo2 = svm->ns_vmexit.exitinfo2;
-            break;
+            fallthrough;
         case VMEXIT_EXCEPTION_NP:
         case VMEXIT_EXCEPTION_SS:
         case VMEXIT_EXCEPTION_GP:
diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c
index 1b32ef77b6..1af7e8edf4 100644
--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -2808,9 +2808,9 @@ void svm_vmexit_handler(void)
 
     case VMEXIT_EXCEPTION_PF:
     {
-        unsigned long va;
-        va = vmcb->exitinfo2;
-        regs->error_code = vmcb->exitinfo1;
+        unsigned long va = vmcb->ei.exc.cr2;
+
+        regs->error_code = vmcb->ei.exc.ec;
         HVM_DBG_LOG(DBG_LEVEL_VMMU,
                     "eax=%lx, ebx=%lx, ecx=%lx, edx=%lx, esi=%lx, edi=%lx",
                     regs->rax, regs->rbx, regs->rcx,
@@ -2838,7 +2838,7 @@ void svm_vmexit_handler(void)
 
     case VMEXIT_EXCEPTION_AC:
         HVMTRACE_1D(TRAP, X86_EXC_AC);
-        hvm_inject_hw_exception(X86_EXC_AC, vmcb->exitinfo1);
+        hvm_inject_hw_exception(X86_EXC_AC, vmcb->ei.exc.ec);
         break;
 
     case VMEXIT_EXCEPTION_UD:
@@ -3051,18 +3051,15 @@ void svm_vmexit_handler(void)
     case VMEXIT_NPF:
         if ( cpu_has_svm_decode )
             v->arch.hvm.svm.cached_insn_len = vmcb->guest_ins_len & 0xf;
-        rc = vmcb->exitinfo1 & PFEC_page_present
-             ? p2m_pt_handle_deferred_changes(vmcb->exitinfo2) : 0;
+        rc = vmcb->ei.npf.ec & PFEC_page_present
+             ? p2m_pt_handle_deferred_changes(vmcb->ei.npf.gpa) : 0;
         if ( rc == 0 )
             /* If no recal adjustments were being made - handle this fault */
-            svm_do_nested_pgfault(v, regs, vmcb->exitinfo1, vmcb->exitinfo2);
+            svm_do_nested_pgfault(v, regs, vmcb->ei.npf.ec, vmcb->ei.npf.gpa);
         else if ( rc < 0 )
-        {
-            printk(XENLOG_G_ERR
-                   "%pv: Error %d handling NPF (gpa=%08lx ec=%04lx)\n",
-                   v, rc, vmcb->exitinfo2, vmcb->exitinfo1);
-            domain_crash(v->domain);
-        }
+            domain_crash(v->domain,
+                         "%pv: Error %d handling NPF (gpa=%08lx ec=%04lx)\n",
+                         v, rc, vmcb->ei.npf.gpa, vmcb->ei.npf.ec);
         v->arch.hvm.svm.cached_insn_len = 0;
         break;
 
diff --git a/xen/arch/x86/include/asm/hvm/svm/vmcb.h 
b/xen/arch/x86/include/asm/hvm/svm/vmcb.h
index 6cd1c4cfe4..8ec2ce6cdf 100644
--- a/xen/arch/x86/include/asm/hvm/svm/vmcb.h
+++ b/xen/arch/x86/include/asm/hvm/svm/vmcb.h
@@ -436,6 +436,12 @@ struct vmcb_struct {
             uint64_t exitinfo2; /* offset 0x80 */
         };
         union {
+            struct {
+                uint32_t ec; /* #NP, #SS, #GP, #PF, #AC */
+                uint32_t :32;
+
+                uint64_t cr2; /* #PF */
+            } exc;
             struct {
                 bool     in:1;
                 bool     :1;
@@ -455,6 +461,10 @@ struct vmcb_struct {
                 uint64_t :59;
                 bool     mov_insn:1; /* MOV, as opposed to LMSW, CLTS, etc */
             } mov_cr;
+            struct {
+                uint64_t ec;
+                uint64_t gpa;
+            } npf;
             struct {
                 uint16_t sel;
                 uint64_t :48;
--
generated by git-patchbot for /home/xen/git/xen.git#master