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>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index d7245cf80261..d02a4f02be13 100644
--- 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.