Revert "arch/x86: Add registers to vm_event"

This reverts commit da61a2102f, because
it breaks !CONFIG_HVM builds.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>

xen/arch/x86/vm_event.c

@@ -122,66 +122,11 @@ void vm_event_monitor_next_interrupt(struct vcpu *v)
     v->arch.monitor.next_interrupt_enabled = true;
 }
 
-static void vm_event_pack_segment_register(enum x86_segment segment,
-                                           struct vm_event_regs_x86 *reg)
-{
-    struct segment_register seg;
-
-    hvm_get_segment_register(current, segment, &seg);
-
-    switch ( segment )
-    {
-    case x86_seg_ss:
-        reg->ss_base = seg.base;
-        reg->ss.limit = seg.g ? seg.limit >> 12 : seg.limit;
-        reg->ss.ar = seg.attr;
-        reg->ss_sel = seg.sel;
-        break;
-
-    case x86_seg_fs:
-        reg->fs_base = seg.base;
-        reg->fs.limit = seg.g ? seg.limit >> 12 : seg.limit;
-        reg->fs.ar = seg.attr;
-        reg->fs_sel = seg.sel;
-        break;
-
-    case x86_seg_gs:
-        reg->gs_base = seg.base;
-        reg->gs.limit = seg.g ? seg.limit >> 12 : seg.limit;
-        reg->gs.ar = seg.attr;
-        reg->gs_sel = seg.sel;
-        break;
-
-    case x86_seg_cs:
-        reg->cs_base = seg.base;
-        reg->cs.limit = seg.g ? seg.limit >> 12 : seg.limit;
-        reg->cs.ar = seg.attr;
-        reg->cs_sel = seg.sel;
-        break;
-
-    case x86_seg_ds:
-        reg->ds_base = seg.base;
-        reg->ds.limit = seg.g ? seg.limit >> 12 : seg.limit;
-        reg->ds.ar = seg.attr;
-        reg->ds_sel = seg.sel;
-        break;
-
-    case x86_seg_es:
-        reg->es_base = seg.base;
-        reg->es.limit = seg.g ? seg.limit >> 12 : seg.limit;
-        reg->es.ar = seg.attr;
-        reg->es_sel = seg.sel;
-        break;
-
-    default:
-        ASSERT_UNREACHABLE();
-    }
-}
-
 void vm_event_fill_regs(vm_event_request_t *req)
 {
 #ifdef CONFIG_HVM
     const struct cpu_user_regs *regs = guest_cpu_user_regs();
+    struct segment_register seg;
     struct hvm_hw_cpu ctxt = {};
     struct vcpu *curr = current;
 
@@ -225,15 +170,14 @@ void vm_event_fill_regs(vm_event_request_t *req)
     req->data.regs.x86.msr_star = ctxt.msr_star;
     req->data.regs.x86.msr_lstar = ctxt.msr_lstar;
 
-    vm_event_pack_segment_register(x86_seg_fs, &req->data.regs.x86);
-    vm_event_pack_segment_register(x86_seg_gs, &req->data.regs.x86);
-    vm_event_pack_segment_register(x86_seg_cs, &req->data.regs.x86);
-    vm_event_pack_segment_register(x86_seg_ss, &req->data.regs.x86);
-    vm_event_pack_segment_register(x86_seg_ds, &req->data.regs.x86);
-    vm_event_pack_segment_register(x86_seg_es, &req->data.regs.x86);
+    hvm_get_segment_register(curr, x86_seg_fs, &seg);
+    req->data.regs.x86.fs_base = seg.base;
 
-    req->data.regs.x86.shadow_gs = ctxt.shadow_gs;
-    req->data.regs.x86.dr6 = ctxt.dr6;
+    hvm_get_segment_register(curr, x86_seg_gs, &seg);
+    req->data.regs.x86.gs_base = seg.base;
+
+    hvm_get_segment_register(curr, x86_seg_cs, &seg);
+    req->data.regs.x86.cs_arbytes = seg.attr;
 #endif
 }
 

xen/include/public/vm_event.h

@@ -29,7 +29,7 @@
 
 #include "xen.h"
 
-#define VM_EVENT_INTERFACE_VERSION 0x00000004
+#define VM_EVENT_INTERFACE_VERSION 0x00000003
 
 #if defined(__XEN__) || defined(__XEN_TOOLS__)
 
@@ -157,12 +157,6 @@
 #define VM_EVENT_X86_CR4    2
 #define VM_EVENT_X86_XCR0   3
 
-/* The limit field is right-shifted by 12 bits if .ar.g is set. */
-struct vm_event_x86_selector_reg {
-    uint32_t limit  :    20;
-    uint32_t ar     :    12;
-};
-
 /*
  * Using custom vCPU structs (i.e. not hvm_hw_cpu) for both x86 and ARM
  * so as to not fill the vm_event ring buffer too quickly.
@@ -185,7 +179,6 @@ struct vm_event_regs_x86 {
     uint64_t r14;
     uint64_t r15;
     uint64_t rflags;
-    uint64_t dr6;
     uint64_t dr7;
     uint64_t rip;
     uint64_t cr0;
@@ -198,25 +191,9 @@ struct vm_event_regs_x86 {
     uint64_t msr_efer;
     uint64_t msr_star;
     uint64_t msr_lstar;
-    uint32_t cs_base;
-    uint32_t ss_base;
-    uint32_t ds_base;
-    uint32_t es_base;
     uint64_t fs_base;
     uint64_t gs_base;
-    struct vm_event_x86_selector_reg cs;
-    struct vm_event_x86_selector_reg ss;
-    struct vm_event_x86_selector_reg ds;
-    struct vm_event_x86_selector_reg es;
-    struct vm_event_x86_selector_reg fs;
-    struct vm_event_x86_selector_reg gs;
-    uint64_t shadow_gs;
-    uint16_t cs_sel;
-    uint16_t ss_sel;
-    uint16_t ds_sel;
-    uint16_t es_sel;
-    uint16_t fs_sel;
-    uint16_t gs_sel;
+    uint32_t cs_arbytes;
     uint32_t _pad;
 };