On 4/10/22 02:26, Rob Landley wrote:
>> FWIW this will do it:
>>
>> qemu-system-m68k -nographic -machine mcf5208evb -kernel vmlinux
>>
>> That will boot an m5208evb_defconfig generated vmlinux.
>> But you will need a user space to get a full boot to login/shell.
>
> No FDPIC support. :(
First stab at switching on CONFIG_BINFMT_FDPIC in the coldfire config and adding
enough stuff to shut up the compiler. Maybe it'll let me load a PIE binary?
Dunno yet, but it compiled a vmlinux that booted to the same panic as the
previous one because I haven't fed it an initramfs yet...
I also had to disable CONFIG_ELF_CORE or else the link died with:
m68k-linux-musl-ld: fs/binfmt_elf_fdpic.o: in function `elf_dump_thread_status':
binfmt_elf_fdpic.c:(.text+0x18): undefined reference to `task_user_regset_view'
make: *** [Makefile:1155: vmlinux] Error 1
But when I did THAT it compiled. :)
diff --git a/arch/m68k/include/asm/elf.h b/arch/m68k/include/asm/elf.h
index 3d387ceaea3f..bcb072396640 100644
--- a/arch/m68k/include/asm/elf.h
+++ b/arch/m68k/include/asm/elf.h
@@ -114,4 +114,6 @@ typedef struct user_m68kfp_struct elf_fpregset_t;
#define ELF_PLATFORM (NULL)
+#define ELF_FDPIC_CORE_EFLAGS 0
+
#endif
diff --git a/arch/m68k/include/asm/mmu.h b/arch/m68k/include/asm/mmu.h
index 5c15aacb1370..6f6d83b731ed 100644
--- a/arch/m68k/include/asm/mmu.h
+++ b/arch/m68k/include/asm/mmu.h
@@ -8,6 +8,10 @@ typedef unsigned long mm_context_t;
#else
typedef struct {
unsigned long end_brk;
+#ifdef CONFIG_BINFMT_ELF_FDPIC
+ unsigned long exec_fdpic_loadmap;
+ unsigned long interp_fdpic_loadmap;
+#endif
} mm_context_t;
#endif
diff --git a/arch/m68k/include/uapi/asm/ptrace.h
b/arch/m68k/include/uapi/asm/ptrace.h
index 19a1b9d0d858..869601381f30 100644
--- a/arch/m68k/include/uapi/asm/ptrace.h
+++ b/arch/m68k/include/uapi/asm/ptrace.h
@@ -71,6 +71,10 @@ struct switch_stack {
#define PTRACE_SETREGS 13
#define PTRACE_GETFPREGS 14
#define PTRACE_SETFPREGS 15
+#define PTRACE_GETFDPIC 31
+
+#define PTRACE_GETFDPIC_EXEC 0
+#define PTRACE_GETFDPIC_INTERP 1
#define PTRACE_GET_THREAD_AREA 25
diff --git a/fs/Kconfig.binfmt b/fs/Kconfig.binfmt
index 4d5ae61580aa..073360aa982c 100644
--- a/fs/Kconfig.binfmt
+++ b/fs/Kconfig.binfmt
@@ -45,7 +45,7 @@ config ARCH_USE_GNU_PROPERTY
config BINFMT_ELF_FDPIC
bool "Kernel support for FDPIC ELF binaries"
default y if !BINFMT_ELF
- depends on (ARM || (SUPERH && !MMU))
+ depends on (ARM || (SUPERH && !MMU) || M68K)
select ELFCORE
help
ELF FDPIC binaries are based on ELF, but allow the individual load
Rob
