Mailing List Archive

# HG changeset patch
# User Keir Fraser <keir.fraser@citrix.com>
# Date 1269329313 0
# Node ID bcc09eb7379fa3717bc95bd235084c09b7a1bed5
# Parent ab5f65e8137cb78afb96036522da5a7d1e00e52b
x86_32: Relocate multiboot modules to below 1GB.

Otherwise Xen cannot access them later during boot. GRUB2 places
modules as high as possible below 4GB, which has been causing boot
failure.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
---
xen/arch/x86/boot/Makefile | 2 +-
xen/arch/x86/boot/build32.mk | 2 +-
xen/arch/x86/boot/reloc.c | 20 ++++++++++++++++++++
3 files changed, 22 insertions(+), 2 deletions(-)

diff -r ab5f65e8137c -r bcc09eb7379f xen/arch/x86/boot/Makefile
--- a/xen/arch/x86/boot/Makefile Mon Mar 22 10:29:42 2010 +0000
+++ b/xen/arch/x86/boot/Makefile Tue Mar 23 07:28:33 2010 +0000
@@ -4,6 +4,6 @@ head.o: reloc.S

BOOT_TRAMPOLINE := $(shell sed -n 's,^\#define[[:space:]]\+BOOT_TRAMPOLINE[[:space:]]\+,,p' $(BASEDIR)/include/asm-x86/config.h)
%.S: %.c
- RELOC=$(BOOT_TRAMPOLINE) $(MAKE) -f build32.mk $@
+ RELOC=$(BOOT_TRAMPOLINE) XEN_BITSPERLONG=$(patsubst x86_%,%,$(TARGET_SUBARCH)) $(MAKE) -f build32.mk $@

reloc.S: $(BASEDIR)/include/asm-x86/config.h
diff -r ab5f65e8137c -r bcc09eb7379f xen/arch/x86/boot/build32.mk
--- a/xen/arch/x86/boot/build32.mk Mon Mar 22 10:29:42 2010 +0000
+++ b/xen/arch/x86/boot/build32.mk Tue Mar 23 07:28:33 2010 +0000
@@ -22,6 +22,6 @@ CFLAGS += -Werror -fno-builtin -msoft-fl
$(LD) $(LDFLAGS_DIRECT) -N -Ttext $(RELOC) -o $@ $<

%.o: %.c
- $(CC) $(CFLAGS) -c $< -o $@
+ $(CC) $(CFLAGS) -DXEN_BITSPERLONG=$(XEN_BITSPERLONG) -c $< -o $@

reloc.o: $(BASEDIR)/include/asm-x86/config.h
diff -r ab5f65e8137c -r bcc09eb7379f xen/arch/x86/boot/reloc.c
--- a/xen/arch/x86/boot/reloc.c Mon Mar 22 10:29:42 2010 +0000
+++ b/xen/arch/x86/boot/reloc.c Tue Mar 23 07:28:33 2010 +0000
@@ -70,8 +70,28 @@ multiboot_info_t *reloc(multiboot_info_t
(module_t *)mbi->mods_addr, mbi->mods_count * sizeof(module_t));
mbi->mods_addr = (u32)mods;
for ( i = 0; i < mbi->mods_count; i++ )
+ {
+#if XEN_BITSPERLONG == 32
+ /*
+ * 32-bit Xen only maps bottom 1GB of memory at boot time.
+ * Relocate modules which extend beyond this (GRUB2 in particular
+ * likes to place modules as high as possible below 4GB).
+ */
+#define BOOTMAP_END (1ul<<30) /* 1GB */
+ static void *mod_alloc = (void *)BOOTMAP_END;
+ u32 mod_len = mods[i].mod_end - mods[i].mod_start;
+ if ( mods[i].mod_end > BOOTMAP_END )
+ {
+ mod_alloc = (void *)
+ (((unsigned long)mod_alloc - mod_len) & ~15ul);
+ mods[i].mod_start = (u32)memcpy(
+ mod_alloc, (char *)mods[i].mod_start, mod_len);
+ mods[i].mod_end = mods[i].mod_start + mod_len;
+ }
+#endif
if ( mods[i].string )
mods[i].string = (u32)reloc_mbi_string((char *)mods[i].string);
+ }
}

if ( mbi->flags & MBI_MEMMAP )

_______________________________________________
Xen-changelog mailing list
Xen-changelog@lists.xensource.com
http://lists.xensource.com/xen-changelog