qemu-stable
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-stable] [Qemu-devel] [PATCH v2] multiboot: Fix bss segment sup


From: Göran Weinholt
Subject: Re: [Qemu-stable] [Qemu-devel] [PATCH v2] multiboot: Fix bss segment support
Date: Tue, 20 Dec 2011 19:49:10 +0100
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux)

Alexander Graf <address@hidden> writes:

> Yes, this patch makes things work again :). Thanks a lot!
>
> The only thing I could nitpick on would be the coding style - checkpatch.pl 
> complains :). Could you please resend with braces?
> Justin, Please also queue this for 1.0-stable when it comes in its final form.
>
> Tested-by: Alexander Graf <address@hidden>

Thanks for testing it. Here it is, with braces this time.


From 2a2df801d68a76fb2210e556652fb2e17e0f6711 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?G=C3=B6ran=20Weinholt?= <address@hidden>
Date: Tue, 20 Dec 2011 19:36:10 +0100
Subject: [PATCH] multiboot: mh_load_end_addr and mh_bss_end_addr may be zero
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

There are two special cases in the address fields of the multiboot
format. If mh_load_end_addr is zero then the whole image file should
be loaded and if mh_bss_end_addr is zero then there is no bss segment.
With this change it is again possible to boot kernels where these
fields are zero.

Signed-off-by: Göran Weinholt <address@hidden>
Tested-by: Alexander Graf <address@hidden>
---
 hw/multiboot.c |   15 ++++++++++++++-
 1 files changed, 14 insertions(+), 1 deletions(-)

diff --git a/hw/multiboot.c b/hw/multiboot.c
index b4484a3..db28328 100644
--- a/hw/multiboot.c
+++ b/hw/multiboot.c
@@ -202,10 +202,23 @@ int load_multiboot(void *fw_cfg,
         uint32_t mh_bss_end_addr = ldl_p(header+i+24);
         mh_load_addr = ldl_p(header+i+16);
         uint32_t mb_kernel_text_offset = i - (mh_header_addr - mh_load_addr);
-        uint32_t mb_load_size = mh_load_end_addr - mh_load_addr;
+        uint32_t mb_load_size;
+
+        /* A load end address of zero indicates that the whole file
+         * should be loaded. */
+        if (!mh_load_end_addr) {
+            mh_load_end_addr = kernel_file_size + mh_load_addr;
+        }
+
+        /* A bss end address of zero indicates that there is no bss
+         * segment. */
+        if (!mh_bss_end_addr) {
+            mh_bss_end_addr = mh_load_end_addr;
+        }
 
         mh_entry_addr = ldl_p(header+i+28);
         mb_kernel_size = mh_bss_end_addr - mh_load_addr;
+        mb_load_size = mh_load_end_addr - mh_load_addr;
 
         /* Valid if mh_flags sets MULTIBOOT_HEADER_HAS_VBE.
         uint32_t mh_mode_type = ldl_p(header+i+32);
-- 
1.7.2.5


-- 
Göran Weinholt <address@hidden>

Attachment: pgpaRQiTZqxgD.pgp
Description: PGP signature


reply via email to

[Prev in Thread] Current Thread [Next in Thread]