freebsd-skq/sys/amd64/linux/linux_locore.s
dchagin c62a8ee2d0 Add a forgotten in r283424 .eh_frame section with CFI & FDE records to allow
stack unwinding through signal handler.

Reported by:	Dmitry Sivachenko
MFC after:	2 weeks
2016-05-09 07:38:47 +00:00

109 lines
2.3 KiB
ArmAsm

/* $FreeBSD$ */
#include "linux_assym.h" /* system definitions */
#include <machine/asmacros.h> /* miscellaneous asm macros */
#include <amd64/linux/linux_syscall.h> /* system call numbers */
.data
.globl linux_platform
linux_platform:
.asciz "x86_64"
.text
/*
* To avoid excess stack frame the signal trampoline code emulates
* the 'call' instruction.
*/
NON_GPROF_ENTRY(linux_rt_sigcode)
movq %rsp, %rbx /* preserve sigframe */
call .getip
.getip:
popq %rax
add $.startrtsigcode-.getip, %rax /* ret address */
pushq %rax
jmp *LINUX_RT_SIGF_HANDLER(%rbx)
.startrtsigcode:
movq $LINUX_SYS_linux_rt_sigreturn,%rax /* linux_rt_sigreturn() */
syscall /* enter kernel with args */
hlt
.endrtsigcode:
0: jmp 0b
NON_GPROF_ENTRY(__vdso_clock_gettime)
movq $LINUX_SYS_linux_clock_gettime,%rax
syscall
ret
.weak clock_gettime
.set clock_gettime, __vdso_clock_gettime
NON_GPROF_ENTRY(__vdso_time)
movq $LINUX_SYS_linux_time,%rax
syscall
ret
.weak time
.set time, __vdso_time
NON_GPROF_ENTRY(__vdso_gettimeofday)
movq $LINUX_SYS_gettimeofday,%rax
syscall
ret
.weak gettimeofday
.set gettimeofday, __vdso_gettimeofday
NON_GPROF_ENTRY(__vdso_getcpu)
movq $-38,%rax /* not implemented */
ret
.weak getcpu
.set getcpu, __vdso_getcpu
#if 0
.section .note.Linux, "a",@note
.long 2f - 1f /* namesz */
.balign 4
.long 4f - 3f /* descsz */
.long 0
1:
.asciz "Linux"
2:
.balign 4
3:
.long LINUX_VERSION_CODE
4:
.balign 4
.previous
#endif
.section .eh_frame,"a",@progbits
.LSTARTFRAMEDLSI0:
.long .LENDCIEDLSI0-.LSTARTCIEDLSI0
.LSTARTCIEDLSI0:
.long 0 /* CIE ID */
.byte 1 /* Version number */
.string "zR" /* NULL-terminated
* augmentation string
*/
.uleb128 1 /* Code alignment factor */
.sleb128 -4 /* Data alignment factor */
.byte 8 /* Return address register column */
.uleb128 1 /* Augmentation value length */
.byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
.byte 0x0c /* DW_CFA_def_cfa */
.uleb128 4
.uleb128 4
.byte 0x88 /* DW_CFA_offset, column 0x8 */
.uleb128 1
.align 4
.LENDCIEDLSI0:
.long .LENDFDEDLSI0-.LSTARTFDEDLSI0 /* Length FDE */
.LSTARTFDEDLSI0:
.long .LSTARTFDEDLSI0-.LSTARTFRAMEDLSI0 /* CIE pointer */
.long .startrtsigcode-. /* PC-relative start address */
.long .endrtsigcode-.startrtsigcode
.uleb128 0
.align 4
.LENDFDEDLSI0:
.previous