x86: avoid SORT_BY_INIT_PRIORITY with old GNU ld

Support for this construct was added in 2.22 only. Avoid the need to
introduce logic to probe for linker script capabilities by (ab)using the
probe for a command line option having appeared at about the same time.

Note that this remains x86-specific because Arm is unaffected, by
requiring GNU ld 2.24 or newer.

Fixes: 4b7fd8153ddf ("x86: fold sections in final binaries")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>

diff --git a/xen/arch/x86/arch.mk b/xen/arch/x86/arch.mk
index fce2ef5b67321f807c9dff66b781167b7b098640..fb86cbda46d2feab82b6fd951022d8dd9c73556b 100644 (file)
--- a/xen/arch/x86/arch.mk
+++ b/xen/arch/x86/arch.mk
@@ -73,6 +73,16 @@ ifeq ($(CONFIG_UBSAN),y)
 $(call cc-option-add,CFLAGS_UBSAN,CC,-fno-sanitize=alignment)
 endif
 
+ifeq ($(CONFIG_LD_IS_GNU),y)
+# While not much better than going by raw GNU ld version, utilize that the
+# feature we're after has appeared in the same release as the
+# --print-output-format command line option.
+AFLAGS-$(call ld-option,--print-output-format) += -DHAVE_LD_SORT_BY_INIT_PRIORITY
+else
+# Assume all versions of LLD support this.
+AFLAGS += -DHAVE_LD_SORT_BY_INIT_PRIORITY
+endif
+
 ifneq ($(CONFIG_PV_SHIM_EXCLUSIVE),y)
 
 efi-check := arch/x86/efi/check

diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S
index d94915ea7d541586fa41d3f9b788c0e9db0ae7a8..8930e14fc40edb2794d12a553554a3c613650acf 100644 (file)
--- a/xen/arch/x86/xen.lds.S
+++ b/xen/arch/x86/xen.lds.S
@@ -36,6 +36,10 @@ ENTRY(start_pa)
 # define SECTION_ALIGN PAGE_SIZE
 #endif
 
+#ifndef HAVE_LD_SORT_BY_INIT_PRIORITY
+# define SORT_BY_INIT_PRIORITY SORT
+#endif
+
 OUTPUT_FORMAT(FORMAT, FORMAT, FORMAT)
 
 OUTPUT_ARCH(i386:x86-64)