Changeset 100877 in vbox for trunk/src/VBox/VMM

Timestamp:

Aug 15, 2023 8:13:22 AM (17 months ago)

Author:

vboxsync

Message:

VMM/NEMR3Native-darwin: Disable intercepting #DB exceptions and mov drX instructions as it currently breaks using a debugger inside the guest. This will break using the hypervisor debugger but only very few people use it anyway and even less on macOS, bugref:10504

File:

• trunk/src/VBox/VMM/VMMR3/NEMR3Native-darwin.cpp (modified) (5 diffs)

trunk/src/VBox/VMM/VMMR3/NEMR3Native-darwin.cpp

@@ -1583 +1583 @@
     }
 
+    /** @todo The DRx handling is not quite correct breaking debugging inside the guest with gdb,
+     * see @ticketref{21413} and @ticketref{21546}, so this is disabled for now. See @bugref{10504}
+     * as well.
+     */
+#if 0
     if (fInterceptMovDRx)
         uProcCtls |= VMX_PROC_CTLS_MOV_DR_EXIT;
     else
         uProcCtls &= ~VMX_PROC_CTLS_MOV_DR_EXIT;
+#endif
 
     /*
@@ -1598 +1604 @@
         pVmcsInfo->u32ProcCtls = uProcCtls;
     }
+
+    /*
+     * Update guest DR7.
+     */
+    int rc = nemR3DarwinWriteVmcs64(pVCpu, VMX_VMCS_GUEST_DR7, u64GuestDr7);
+    AssertRC(rc);
 
     /*
@@ -1611 +1623 @@
 
         uint32_t fIntrState = 0;
-        int rc = nemR3DarwinReadVmcs32(pVCpu, VMX_VMCS32_GUEST_INT_STATE, &fIntrState);
+        rc = nemR3DarwinReadVmcs32(pVCpu, VMX_VMCS32_GUEST_INT_STATE, &fIntrState);
         AssertRC(rc);
 
@@ -2676 +2688 @@
     uint32_t const fZap = g_HmMsrs.u.vmx.ProcCtls.n.allowed1;     /* Bits cleared here must be cleared in the VMCS. */
 
+    /** @todo The DRx handling is not quite correct breaking debugging inside the guest with gdb,
+     * see @ticketref{21413} and @ticketref{21546}, so intercepting mov drX is disabled for now. See @bugref{10504}
+     * as well. This will break the hypervisor debugger but only very few people use it and even less on macOS
+     * using the NEM backend.
+     */
     fVal |= VMX_PROC_CTLS_HLT_EXIT                                    /* HLT causes a VM-exit. */
 //         |  VMX_PROC_CTLS_USE_TSC_OFFSETTING                          /* Use TSC-offsetting. */
-         |  VMX_PROC_CTLS_MOV_DR_EXIT                                 /* MOV DRx causes a VM-exit. */
+//         |  VMX_PROC_CTLS_MOV_DR_EXIT                                 /* MOV DRx causes a VM-exit. */
          |  VMX_PROC_CTLS_UNCOND_IO_EXIT                              /* All IO instructions cause a VM-exit. */
          |  VMX_PROC_CTLS_RDPMC_EXIT                                  /* RDPMC causes a VM-exit. */
@@ -2783 +2800 @@
      *       recursive #DBs can cause a CPU hang.
      */
+    /** @todo The DRx handling is not quite correct breaking debugging inside the guest with gdb,
+     * see @ticketref{21413} and @ticketref{21546}, so intercepting #DB is disabled for now. See @bugref{10504}
+     * as well. This will break the hypervisor debugger but only very few people use it and even less on macOS
+     * using the NEM backend.
+     */
     uint32_t const uXcptBitmap = RT_BIT(X86_XCPT_AC)
-                               | RT_BIT(X86_XCPT_DB);
+                               /*| RT_BIT(X86_XCPT_DB)*/;
 
     /* Commit it to the VMCS. */