x86: printk kernel version in WARN_ON and other dump_stack users

[linux-2.6] / arch / x86 / kernel / head_32.S

diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 0fa8a972a679c33bed140b1719f38a5107d7e845..374b7ece89610e14fcebff09dd0711d27da040ff 100644 (file)
--- 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
@@ -116,18 +124,42 @@ ENTRY(startup_32)
        movsl
        movl boot_params - __PAGE_OFFSET + NEW_CL_POINTER,%esi
        andl %esi,%esi
-       jnz 2f                  # New command line protocol
-       cmpw $(OLD_CL_MAGIC),OLD_CL_MAGIC_ADDR
-       jne 1f
-       movzwl OLD_CL_OFFSET,%esi
-       addl $(OLD_CL_BASE_ADDR),%esi
-2:
+       jz 1f                   # No comand line
        movl $(boot_command_line - __PAGE_OFFSET),%edi
        movl $(COMMAND_LINE_SIZE/4),%ecx
        rep
        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 +172,7 @@ 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 */
@@ -452,6 +485,7 @@ early_page_fault:
 early_fault:
        cld
 #ifdef CONFIG_PRINTK
+       pusha
        movl $(__KERNEL_DS),%eax
        movl %eax,%ds
        movl %eax,%es
@@ -543,8 +577,15 @@ int_msg:
        .asciz "Unknown interrupt or fault at EIP %p %p %p\n"
 
 fault_msg:
-       .ascii "Int %d: CR2 %p  err %p  EIP %p  CS %p  flags %p\n"
-       .asciz "Stack: %p %p %p %p %p %p %p %p\n"
+       .ascii                                                          \
+/* fault info: */      "BUG: Int %d: CR2 %p\n"                         \
+/* pusha regs: */      "     EDI %p  ESI %p  EBP %p  ESP %p\n"         \
+                       "     EBX %p  EDX %p  ECX %p  EAX %p\n"         \
+/* fault frame: */     "     err %p  EIP %p   CS %p  flg %p\n"         \
+                                                                       \
+                       "Stack: %p %p %p %p %p %p %p %p\n"              \
+                       "       %p %p %p %p %p %p %p %p\n"              \
+                       "       %p %p %p %p %p %p %p %p\n"
 
 #include "../../x86/xen/xen-head.S"