elfnotes: check phys_entry against UNSET_ADDR32

And introduce UNSET_ADDR32.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>

tools/libxc/xc_dom_elfloader.c

@@ -57,7 +57,7 @@ static char *xc_dom_guest_type(struct xc_dom_image *dom,
     uint64_t machine = elf_uval(elf, elf->ehdr, e_machine);
 
     if ( dom->container_type == XC_DOM_HVM_CONTAINER &&
-         dom->parms.phys_entry != UNSET_ADDR )
+         dom->parms.phys_entry != UNSET_ADDR32 )
         return "hvm-3.0-x86_32";
 
     switch ( machine )

xen/common/libelf/libelf-dominfo.c

@@ -503,6 +503,7 @@ elf_errorstatus elf_xen_parse(struct elf_binary *elf,
     parms->virt_hv_start_low = UNSET_ADDR;
     parms->p2m_base = UNSET_ADDR;
     parms->elf_paddr_offset = UNSET_ADDR;
+    parms->phys_entry = UNSET_ADDR32;
 
     /* Find and parse elf notes. */
     count = elf_phdr_count(elf);

xen/include/xen/libelf.h

@@ -386,6 +386,7 @@ elf_errorstatus elf_reloc(struct elf_binary *elf);
 /* xc_libelf_dominfo.c                                                      */
 
 #define UNSET_ADDR          ((uint64_t)-1)
+#define UNSET_ADDR32        ((uint32_t)-1)
 
 enum xen_elfnote_type {
     XEN_ENT_NONE = 0,