[Qemu-devel] [PATCH] fix entry pointer for ELF kernels loaded with -kernel option

[Henning Schild]

This patch fixes a bug in qemu which prevents Multiboot ELF kernels 
from being loaded with the -kernel option. Find a full description of 
the problem here https://bugs.launchpad.net/qemu/+bug/1044727 .

---
 hw/elf_ops.h |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/hw/elf_ops.h b/hw/elf_ops.h
index fa65ce2..aeddd11 100644
--- a/hw/elf_ops.h
+++ b/hw/elf_ops.h
@@ -269,6 +269,16 @@ static int glue(load_elf, SZ)(const char *name, 
int fd,
                 addr = ph->p_paddr;
             }

+            /* the entry pointer in the ELF header is a virtual
+             * address, if the text segments paddr and vaddr differ
+             * we need to adjust the entry */
+            if (pentry && !translate_fn &&
+                ph->p_vaddr != ph->p_paddr &&
+                ehdr.e_entry >= ph->p_vaddr &&
+                ehdr.e_entry < ph->p_vaddr + ph->p_filesz &&
+                ph->p_flags & PF_X)
+                    *pentry = ehdr.e_entry - ph->p_vaddr + 
ph->p_paddr;
+
             snprintf(label, sizeof(label), "phdr #%d: %s", i, name);
             rom_add_blob_fixed(label, data, mem_size, addr);

--
1.7.8.6