[v6,10/11] tools/libguest: Set distinct x2APIC IDs for each vCPU

Commit Message

Alejandro Vallejo Oct. 1, 2024, 12:38 p.m. UTC

Have toolstack populate the new x2APIC ID in the LAPIC save record with
the proper IDs intended for each vCPU.

Signed-off-by: Alejandro Vallejo <[e-mail]>
---
v6:
  * Rely on the new LUT in xc_dom_image rather than recalculating APIC IDs.
---
 tools/libs/guest/xg_dom_x86.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

Patch

diff --git a/tools/libs/guest/xg_dom_x86.c b/tools/libs/guest/xg_dom_x86.c
index c98229317db7..38486140ed15 100644
--- a/tools/libs/guest/xg_dom_x86.c
+++ b/tools/libs/guest/xg_dom_x86.c
@@ -1004,11 +1004,14 @@  static int vcpu_hvm(struct xc_dom_image *dom)
         HVM_SAVE_TYPE(HEADER) header;
         struct hvm_save_descriptor mtrr_d;
         HVM_SAVE_TYPE(MTRR) mtrr;
+        struct hvm_save_descriptor lapic_d;
+        HVM_SAVE_TYPE(LAPIC) lapic;
         struct hvm_save_descriptor end_d;
         HVM_SAVE_TYPE(END) end;
     } vcpu_ctx;
-    /* Context from full_ctx */
+    /* Contexts from full_ctx */
     const HVM_SAVE_TYPE(MTRR) *mtrr_record;
+    const HVM_SAVE_TYPE(LAPIC) *lapic_record;
     /* Raw context as taken from Xen */
     uint8_t *full_ctx = NULL;
     int rc;
@@ -1111,6 +1114,8 @@  static int vcpu_hvm(struct xc_dom_image *dom)
     vcpu_ctx.mtrr_d.typecode = HVM_SAVE_CODE(MTRR);
     vcpu_ctx.mtrr_d.length = HVM_SAVE_LENGTH(MTRR);
     vcpu_ctx.mtrr = *mtrr_record;
+    vcpu_ctx.lapic_d.typecode = HVM_SAVE_CODE(LAPIC);
+    vcpu_ctx.lapic_d.length = HVM_SAVE_LENGTH(LAPIC);
     vcpu_ctx.end_d = bsp_ctx.end_d;
     vcpu_ctx.end = bsp_ctx.end;
 
@@ -1125,6 +1130,18 @@  static int vcpu_hvm(struct xc_dom_image *dom)
     {
         vcpu_ctx.mtrr_d.instance = i;
 
+        lapic_record = hvm_get_save_record(full_ctx, HVM_SAVE_CODE(LAPIC), i);
+        if ( !lapic_record )
+        {
+            xc_dom_panic(dom->xch, XC_INTERNAL_ERROR,
+                         "%s: unable to get LAPIC[%d] save record", __func__, i);
+            goto out;
+        }
+
+        vcpu_ctx.lapic = *lapic_record;
+        vcpu_ctx.lapic.x2apic_id = dom->cpu_to_apicid[i];
+        vcpu_ctx.lapic_d.instance = i;
+
         rc = xc_domain_hvm_setcontext(dom->xch, dom->guest_domid,
                                       (uint8_t *)&vcpu_ctx, sizeof(vcpu_ctx));
         if ( rc != 0 )