x86, boot: zero EFLAGS on 32 bits

The 64-bit code already clears EFLAGS as soon as it has a stack.  This
seems like a reasonable precaution, so do it on 32 bits as well.

[ Impact: extra paranoia ]

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index d7245cf80261773336d6c927392e481a37eb80c4..d02a4f02be138bac46e0c7d54687f51a7dcddf17 100644 (file)
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -91,6 +91,10 @@ ENTRY(startup_32)
        /* Set up the stack */
        leal    boot_stack_end(%ebx), %esp
 
+       /* Zero EFLAGS */
+       pushl   $0
+       popfl
+
 /*
  * Copy the compressed kernel to the end of our buffer
  * where decompression in place becomes safe.