Re: [PATCH v3 11/12] x86, boot: add fields to support load bzImageand ramdisk high
From: H. Peter Anvin
Date: Thu Nov 22 2012 - 15:51:23 EST
On 11/22/2012 12:18 PM, Yinghai Lu wrote:
If we can get the sentinel hack to work that would probably be useful, but
we need to understand the exact pathology.
for kexec bzImage --real-mode-entry, code after setup_header will be executed.
so we could clear value before setup_header after copy 16bit section
from bzImage...
Index: kexec-tools/kexec/arch/i386/kexec-bzImage.c
===================================================================
--- kexec-tools.orig/kexec/arch/i386/kexec-bzImage.c
+++ kexec-tools/kexec/arch/i386/kexec-bzImage.c
@@ -212,6 +212,16 @@ int do_bzImage_load(struct kexec_info *i
setup_size = kern16_size + command_line_len + PURGATORY_CMDLINE_SIZE;
real_mode = xmalloc(setup_size);
memcpy(real_mode, kernel, kern16_size);
+ /*
+ * clear value before header
+ * not not clear value after header, --real-mode-entry
+ * need code after header.
+ */
+ memset(real_mode, 0, 0x1f1);
+ if (!real_mode_entry) {
+ /* clear value after setup_header */
+ memset((unsigned char *)real_mode + 0x290, 0, kern16_size - 0x290);
+ }
You really should move the memset() into the if() clause as well...
doesn't matter at the moment, but that is the protocol.
The limit is 0x280, not 0x290, or -- better -- you can use the byte at
0x201 to get the size.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
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