xen/public: Obsolete HVM_PARAM_PAE_ENABLED

Xen has never acted upon the value of HVM_PARAM_PAE_ENABLED, contrary perhaps
to expectations based on how other boolean fields work.

It was only ever used as a non-standard calling convention for
xc_cpuid_apply_policy() but that has been fixed now.

Purge its use, and any possible confusion over its behaviour, by having Xen
reject any attempts to use it.  Forgo setting it up in libxl's
hvm_set_conf_params().  The only backwards compatibility necessary is to have
the HVM restore stream discard it if found.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>

diff --git a/tools/libxc/xc_sr_restore_x86_hvm.c b/tools/libxc/xc_sr_restore_x86_hvm.c
index 3f78248f32fec239db77b0e483b0195211e6b974..adbdf1ae5f97da4db74c0d8129832faabb012277 100644 (file)
--- a/tools/libxc/xc_sr_restore_x86_hvm.c
+++ b/tools/libxc/xc_sr_restore_x86_hvm.c
@@ -72,6 +72,16 @@ static int handle_hvm_params(struct xc_sr_context *ctx,
         case HVM_PARAM_BUFIOREQ_PFN:
             xc_clear_domain_page(xch, ctx->domid, entry->value);
             break;
+
+        case HVM_PARAM_PAE_ENABLED:
+            /*
+             * This HVM_PARAM only ever existed to pass data into
+             * xc_cpuid_apply_policy().  The function has now been updated to
+             * use a normal calling convention, making the param obsolete.
+             *
+             * Discard if we find it in an old migration stream.
+             */
+            continue;
         }
 
         rc = xc_hvm_param_set(xch, ctx->domid, entry->index, entry->value);

diff --git a/tools/libxc/xc_sr_save_x86_hvm.c b/tools/libxc/xc_sr_save_x86_hvm.c
index d99efe65e50ca55c52af1a8b38b1d9ef2f3b2f11..7d3f3ddb8fce15e4a3b532bf3a08afa4775b3a29 100644 (file)
--- a/tools/libxc/xc_sr_save_x86_hvm.c
+++ b/tools/libxc/xc_sr_save_x86_hvm.c
@@ -71,7 +71,6 @@ static int write_hvm_params(struct xc_sr_context *ctx)
         HVM_PARAM_ACPI_IOPORTS_LOCATION,
         HVM_PARAM_VIRIDIAN,
         HVM_PARAM_IDENT_PT,
-        HVM_PARAM_PAE_ENABLED,
         HVM_PARAM_VM_GENERATION_ID_ADDR,
         HVM_PARAM_IOREQ_SERVER_PFN,
         HVM_PARAM_NR_IOREQ_SERVER_PAGES,

diff --git a/tools/libxl/libxl_x86.c b/tools/libxl/libxl_x86.c
index 1cae0e2b26a9d569625b70f96a978e6a1ae0c870..f8bc828e623de1b37ce4b896fdb0fb3436a59e8f 100644 (file)
--- a/tools/libxl/libxl_x86.c
+++ b/tools/libxl/libxl_x86.c
@@ -391,12 +391,10 @@ static int hvm_set_conf_params(libxl__gc *gc, uint32_t domid,
     libxl_ctx *ctx = libxl__gc_owner(gc);
     xc_interface *xch = ctx->xch;
     int ret = ERROR_FAIL;
-    bool pae = true, altp2m = info->altp2m;
+    bool altp2m = info->altp2m;
 
     switch(info->type) {
     case LIBXL_DOMAIN_TYPE_HVM:
-        pae = libxl_defbool_val(info->u.hvm.pae);
-
         /* The config parameter "altp2m" replaces the parameter "altp2mhvm". For
          * legacy reasons, both parameters are accepted on x86 HVM guests.
          *
@@ -425,10 +423,6 @@ static int hvm_set_conf_params(libxl__gc *gc, uint32_t domid,
 
         /* Fallthrough */
     case LIBXL_DOMAIN_TYPE_PVH:
-        if (xc_hvm_param_set(xch, domid, HVM_PARAM_PAE_ENABLED, pae)) {
-            LOG(ERROR, "Couldn't set HVM_PARAM_PAE_ENABLED");
-            goto out;
-        }
         if (xc_hvm_param_set(xch, domid, HVM_PARAM_TIMER_MODE,
                              timer_mode(info))) {
             LOG(ERROR, "Couldn't set HVM_PARAM_TIMER_MODE");

diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index 93795dab928fb482e90ef1abddf43b39adf33d63..a339b36a0ddf37d2c6253638ecb6292fb2312b73 100644 (file)
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -4104,6 +4104,7 @@ static int hvm_allow_set_param(struct domain *d,
     case HVM_PARAM_X87_FIP_WIDTH:
         break;
     /* The following parameters are deprecated. */
+    case HVM_PARAM_PAE_ENABLED:
     case HVM_PARAM_DM_DOMAIN:
     case HVM_PARAM_MEMORY_EVENT_CR0:
     case HVM_PARAM_MEMORY_EVENT_CR3:
@@ -4407,6 +4408,7 @@ static int hvm_allow_get_param(struct domain *d,
     case HVM_PARAM_X87_FIP_WIDTH:
         break;
     /* The following parameters are deprecated. */
+    case HVM_PARAM_PAE_ENABLED:
     case HVM_PARAM_DM_DOMAIN:
     case HVM_PARAM_MEMORY_EVENT_CR0:
     case HVM_PARAM_MEMORY_EVENT_CR3:

diff --git a/xen/include/public/hvm/params.h b/xen/include/public/hvm/params.h
index 68293e314e1a2c0988c449086b88893df4a8c687..0a91bfa749b413f73296dbbf14456990eb12c928 100644 (file)
--- a/xen/include/public/hvm/params.h
+++ b/xen/include/public/hvm/params.h
@@ -28,6 +28,7 @@
 /* These parameters are deprecated and their meaning is undefined. */
 #if defined(__XEN__) || defined(__XEN_TOOLS__)
 
+#define HVM_PARAM_PAE_ENABLED                4
 #define HVM_PARAM_DM_DOMAIN                 13
 #define HVM_PARAM_MEMORY_EVENT_CR0          20
 #define HVM_PARAM_MEMORY_EVENT_CR3          21
@@ -92,8 +93,6 @@
 #define HVM_PARAM_STORE_PFN    1
 #define HVM_PARAM_STORE_EVTCHN 2
 
-#define HVM_PARAM_PAE_ENABLED  4
-
 #define HVM_PARAM_IOREQ_PFN    5
 
 #define HVM_PARAM_BUFIOREQ_PFN 6