Oleg Endo a écrit :
On Sat, 2013-06-22 at 21:38 +0200, BERTRAND Joël wrote:
Oleg Endo a écrit :
The code in idt.c compiled with 4.6 puts static initialization functions
into the .ctors section, while 4.7 puts them into the .init_array
section. Probably this happens only for this single file in the whole
kernel. My guess is that the .init_array section is not handled
properly by the startup code of the kernel. Or maybe it's even stripped
out completely (missing in the linker script). Either way, it seems
that static initialization for idt.c is not being done properly and thus
the code crashes.
I don't think that ctors are stripped by linker script. This script is
built by makefile. Here is my script :
OUTPUT_FORMAT("elf64-x86-64")
OUTPUT_ARCH("i386:x86-64")
BOOTMEM_SIZE = 1024K;
...
As I initially assumed, the .init_array section seems to be missing in
the linker script, so it gets stripped. The .init_array section has to
be handled for code generated by GCC 4.7. I would say this is an issue
of the L4 software, not GCC.
OK. I have done some test since yesterday. I have tried to include
.init_array in kernel.
If I modify my linker script like this :
SECTIONS
{
. = ALIGN(4k);
.text _start_text : AT (ADDR(.text) - KERNEL_OFFSET)
{
*(.text);
*(.gnu.linkonce.*);
*(.spinlock);
}
. = ALIGN(4k);
.init_array . : AT (ADDR(.init_array) - KERNEL_OFFSET)
{
PROVIDE_HIDDEN (__init_array_start = .);
KEEP (*(SORT(.init_array.*)))
KEEP (*(.init_array))
PROVIDE_HIDDEN (__init_array_end = .);
}
. = ALIGN(4k);
.rodata . : AT (ADDR(.rodata) - KERNEL_OFFSET)
...
I obtain a kernel with an .init_array section. But result is the same as
I suppose that kickstart does not load this new section in memory.
I have tried to write .init_array in .text section with :
.text _start_text : AT (ADDR(.text) - KERNEL_OFFSET)
{
*(.text);
*(.gnu.linkonce.*);
*(.spinlock);
PROVIDE_HIDDEN (__init_array_start = .);
KEEP (*(SORT(.init_array.*)))
KEEP (*(.init_array))
PROVIDE_HIDDEN (__init_array_end = .);
}
I believe that .init_array is included in text section and loaded by
kickstart into memory, but kernel only reboots too.
Regards,
JKB
