[PATCH] x86-64: Move cpu verification code to common file
o This patch moves the code to verify long mode and SSE to a common file.
This code is now shared by trampoline.S, wakeup.S, boot/setup.S and
boot/compressed/head.S
o So far we used to do very limited check in trampoline.S, wakeup.S and
in 32bit entry point. Now all the entry paths are forced to do the
exhaustive check, including SSE because verify_cpu is shared.
o I am keeping this patch as last in the x86 relocatable series because
previous patches have got quite some amount of testing done and don't want
to distrub that. So that if there is problem introduced by this patch, at
least it can be easily isolated.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
diff --git a/arch/x86_64/boot/compressed/head.S b/arch/x86_64/boot/compressed/head.S
index c353a92..f9d5692 100644
--- a/arch/x86_64/boot/compressed/head.S
+++ b/arch/x86_64/boot/compressed/head.S
@@ -54,6 +54,15 @@
1: popl %ebp
subl $1b, %ebp
+/* setup a stack and make sure cpu supports long mode. */
+ movl $user_stack_end, %eax
+ addl %ebp, %eax
+ movl %eax, %esp
+
+ call verify_cpu
+ testl %eax, %eax
+ jnz no_longmode
+
/* Compute the delta between where we were compiled to run at
* and where the code will actually run at.
*/
@@ -159,13 +168,21 @@
/* Jump from 32bit compatibility mode into 64bit mode. */
lret
+no_longmode:
+ /* This isn't an x86-64 CPU so hang */
+1:
+ hlt
+ jmp 1b
+
+#include "../../kernel/verify_cpu.S"
+
/* Be careful here startup_64 needs to be at a predictable
* address so I can export it in an ELF header. Bootloaders
* should look at the ELF header to find this address, as
* it may change in the future.
*/
.code64
- .org 0x100
+ .org 0x200
ENTRY(startup_64)
/* We come here either from startup_32 or directly from a
* 64bit bootloader. If we come here from a bootloader we depend on