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-rw-r--r--arch/x86/boot/compressed/head_32.S15
-rw-r--r--arch/x86/boot/compressed/misc_32.c3
-rw-r--r--arch/x86/boot/header.S7
-rw-r--r--arch/x86/kernel/head_32.S44
4 files changed, 63 insertions, 6 deletions
diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index f35ea2237522..a0ae2e7f6cec 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -27,13 +27,22 @@
#include <asm/segment.h>
#include <asm/page.h>
#include <asm/boot.h>
+#include <asm/asm-offsets.h>
.section ".text.head","ax",@progbits
.globl startup_32
startup_32:
- cld
- cli
+ /* check to see if KEEP_SEGMENTS flag is meaningful */
+ cmpw $0x207, BP_version(%esi)
+ jb 1f
+
+ /* test KEEP_SEGMENTS flag to see if the bootloader is asking
+ * us to not reload segments */
+ testb $(1<<6), BP_loadflags(%esi)
+ jnz 2f
+
+1: cli
movl $(__BOOT_DS),%eax
movl %eax,%ds
movl %eax,%es
@@ -41,6 +50,8 @@ startup_32:
movl %eax,%gs
movl %eax,%ss
+2: cld
+
/* Calculate the delta between where we were compiled to run
* at and where we were actually loaded at. This can only be done
* with a short local call on x86. Nothing else will tell us what
diff --git a/arch/x86/boot/compressed/misc_32.c b/arch/x86/boot/compressed/misc_32.c
index 1dc1e19c0a9f..b74d60d1b2fa 100644
--- a/arch/x86/boot/compressed/misc_32.c
+++ b/arch/x86/boot/compressed/misc_32.c
@@ -247,6 +247,9 @@ static void putstr(const char *s)
int x,y,pos;
char c;
+ if (RM_SCREEN_INFO.orig_video_mode == 0 && lines == 0 && cols == 0)
+ return;
+
x = RM_SCREEN_INFO.orig_x;
y = RM_SCREEN_INFO.orig_y;
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index f3140e596d40..8353c81c41c0 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -119,7 +119,7 @@ _start:
# Part 2 of the header, from the old setup.S
.ascii "HdrS" # header signature
- .word 0x0206 # header version number (>= 0x0105)
+ .word 0x0207 # header version number (>= 0x0105)
# or else old loadlin-1.5 will fail)
.globl realmode_swtch
realmode_swtch: .word 0, 0 # default_switch, SETUPSEG
@@ -214,6 +214,11 @@ cmdline_size: .long COMMAND_LINE_SIZE-1 #length of the command line,
#added with boot protocol
#version 2.06
+hardware_subarch: .long 0 # subarchitecture, added with 2.07
+ # default to 0 for normal x86 PC
+
+hardware_subarch_data: .quad 0
+
# End of setup header #####################################################
.section ".inittext", "ax"
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 39677965e161..00b1c2c56454 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -79,22 +79,30 @@ INIT_MAP_BEYOND_END = BOOTBITMAP_SIZE + (PAGE_TABLE_SIZE + ALLOCATOR_SLOP)*PAGE_
*/
.section .text.head,"ax",@progbits
ENTRY(startup_32)
+ /* check to see if KEEP_SEGMENTS flag is meaningful */
+ cmpw $0x207, BP_version(%esi)
+ jb 1f
+
+ /* test KEEP_SEGMENTS flag to see if the bootloader is asking
+ us to not reload segments */
+ testb $(1<<6), BP_loadflags(%esi)
+ jnz 2f
/*
* Set segments to known values.
*/
- cld
- lgdt boot_gdt_descr - __PAGE_OFFSET
+1: lgdt boot_gdt_descr - __PAGE_OFFSET
movl $(__BOOT_DS),%eax
movl %eax,%ds
movl %eax,%es
movl %eax,%fs
movl %eax,%gs
+2:
/*
* Clear BSS first so that there are no surprises...
- * No need to cld as DF is already clear from cld above...
*/
+ cld
xorl %eax,%eax
movl $__bss_start - __PAGE_OFFSET,%edi
movl $__bss_stop - __PAGE_OFFSET,%ecx
@@ -128,6 +136,35 @@ ENTRY(startup_32)
movsl
1:
+#ifdef CONFIG_PARAVIRT
+ cmpw $0x207, (boot_params + BP_version - __PAGE_OFFSET)
+ jb default_entry
+
+ /* Paravirt-compatible boot parameters. Look to see what architecture
+ we're booting under. */
+ movl (boot_params + BP_hardware_subarch - __PAGE_OFFSET), %eax
+ cmpl $num_subarch_entries, %eax
+ jae bad_subarch
+
+ movl subarch_entries - __PAGE_OFFSET(,%eax,4), %eax
+ subl $__PAGE_OFFSET, %eax
+ jmp *%eax
+
+bad_subarch:
+WEAK(lguest_entry)
+WEAK(xen_entry)
+ /* Unknown implementation; there's really
+ nothing we can do at this point. */
+ ud2a
+.data
+subarch_entries:
+ .long default_entry /* normal x86/PC */
+ .long lguest_entry /* lguest hypervisor */
+ .long xen_entry /* Xen hypervisor */
+num_subarch_entries = (. - subarch_entries) / 4
+.previous
+#endif /* CONFIG_PARAVIRT */
+
/*
* Initialize page tables. This creates a PDE and a set of page
* tables, which are located immediately beyond _end. The variable
@@ -140,6 +177,7 @@ ENTRY(startup_32)
*/
page_pde_offset = (__PAGE_OFFSET >> 20);
+default_entry:
movl $(pg0 - __PAGE_OFFSET), %edi
movl $(swapper_pg_dir - __PAGE_OFFSET), %edx
movl $0x007, %eax /* 0x007 = PRESENT+RW+USER */