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;
_start_text_phys = 0x600000;
_start_text = _start_text_phys + 0xFFFFFFFFC0000000;
SECTIONS
{
. = ALIGN(4k);
.text _start_text : AT (ADDR(.text) - 0xFFFFFFFFC0000000)
{
*(.text);
*(.gnu.linkonce.*);
*(.spinlock);
}
. = ALIGN(4k);
.rodata . : AT (ADDR(.rodata) - 0xFFFFFFFFC0000000)
{
*(.rodata);
*(.rodata.*);
}
. = ALIGN(4K);
.kip . : AT (ADDR(.kip) - 0xFFFFFFFFC0000000)
{
*(.data.kip)
*(.data.kip.pdesc)
*(.data.kip.kdesc)
*(.data.kip.versionparts)
*(.data.kip.features)
*(.data.kip.features.end)
. = ALIGN(16);
*(.data.kip.mdesc)
_memory_descriptors_raw = ABSOLUTE((_memory_descriptors_offset << 32)
+ _memory_descriptors_size);
}
_memory_descriptors_offset = memory_descriptors - kip;
_memory_descriptors_size =
(4K - ((memory_descriptors - kip) & (4K-1))) / 16;
. = ALIGN(((1 << 21)));
_start_syscalls = .;
.syscalls . : AT (ADDR(.syscalls) - 0xFFFFFFFFC0000000)
{
*(.user.syscall.ipc);
. = ALIGN((0x100));
*(.user.syscall.lipc);
. = ALIGN((0x100));
*(.user.syscall.exregs);
. = ALIGN((0x100));
*(.user.syscall.threadctrl);
. = ALIGN((0x100));
*(.user.syscall.sysclock);
. = ALIGN((0x100));
*(.user.syscall.threadswtch);
. = ALIGN((0x100));
*(.user.syscall.schedule);
. = ALIGN((0x100));
*(.user.syscall.unmap);
. = ALIGN((0x100));
*(.user.syscall.spacectrl);
. = ALIGN((0x100));
*(.user.syscall.procctrl);
. = ALIGN((0x100));
*(.user.syscall.memctrl);
}
. = ALIGN(((1 << 21)));
_end_syscalls = .;
. = ALIGN(((1 << 21)));
_start_cpu_local = .;
.cpulocal . : AT (ADDR(.cpulocal) - 0xFFFFFFFFC0000000)
{
*(.data.cpulocal)
*(.data.x86.cpulocal)
}
. = ALIGN(((1 << 21)));
_end_cpu_local = .;
.data . : AT (ADDR(.data) - 0xFFFFFFFFC0000000)
{
*(.sdata);
*(.data);
*(.data.x86.idt);
*(.data.x86.exc_all);
*(.data.x86.exc_common);
*(.data.*);
_start_bss = .;
*(.bss);
_end_bss = .;
}
. = ALIGN(4K);
.kdebug . : AT(ADDR(.kdebug) - 0xFFFFFFFFC0000000)
{
*(.kdebug);
*(.kdebug-bss);
*(.comment);
}
. = ALIGN(4K);
.sets . : AT(ADDR(.sets) - 0xFFFFFFFFC0000000)
{
. = ALIGN(16);
_start_setlist = .;
*(.setlist)
_end_setlist = .;
. = ALIGN(16);
_start_sets = .;
*(SORT(set_*))
_end_sets = .;
}
. = ALIGN(4K);
_end_text = .;
. = ALIGN(4K);
_start_bootmem = .;
. = . + BOOTMEM_SIZE;
_end_bootmem = .;
. = ALIGN(4K);
_start_init = . - 0xFFFFFFFFC0000000;
.init (. - 0xFFFFFFFFC0000000) : AT(ADDR(.init))
{
*(.init.startup32);
. = ALIGN(1K);
*(.init.init32) FILL(0x90909090);
. = . + 1K;
. = ALIGN(1K);
*(.init.init64);
*(.init);
*(.roinit);
*(.init.data);
*(.init.memory);
*(.init.cpulocal);
*(.init.*);
. = ALIGN(16);
_start_mdb_funcs = .;
*(SORT(.mdb_funcs*))
_end_mdb_funcs = .;
. = ALIGN(16);
/* cpu-local static initializers */
__ctors_CPU__ = .;
*(SORT(.ctors.3*))
QUAD(0)
/* node-local static initializers */
__ctors_NODE__ = .;
*(SORT(.ctors.2*))
QUAD(0)
/* global static initializers */
__ctors_GLOBAL__ = .;
*(SORT(.ctors.1*))
*(SORT(.ctors.*))
*(.ctors)
QUAD(0)
}
_end_init = .;
/* special section that is discarded during linking
all unwanted sections should go here */
. = ALIGN(4K);
/DISCARD/ :
{
*(.eh_frame);
*(.note);
*(.comment);
}
}
/* physical addresses */
_end_text_phys = _end_text - 0xFFFFFFFFC0000000;
_start_syscalls_phys = _start_syscalls - 0xFFFFFFFFC0000000;
_end_syscalls_phys = _end_syscalls - 0xFFFFFFFFC0000000;
_start_bootmem_phys = _start_bootmem - 0xFFFFFFFFC0000000;
_end_bootmem_phys = _end_bootmem - 0xFFFFFFFFC0000000;
Regards,
JKB
