diff options
Diffstat (limited to 'qemu/roms/ipxe/src/arch/i386/core/gdbidt.S')
| -rw-r--r-- | qemu/roms/ipxe/src/arch/i386/core/gdbidt.S | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/arch/i386/core/gdbidt.S b/qemu/roms/ipxe/src/arch/i386/core/gdbidt.S new file mode 100644 index 000000000..a1e309d7c --- /dev/null +++ b/qemu/roms/ipxe/src/arch/i386/core/gdbidt.S @@ -0,0 +1,140 @@ +/* + * Interrupt handlers for GDB stub + */ + +#define SIZEOF_I386_REGS 32 +#define SIZEOF_I386_FLAGS 4 + +/**************************************************************************** + * Interrupt handlers + **************************************************************************** + */ + .section ".text", "ax", @progbits + .code32 + +/* POSIX signal numbers for reporting traps to GDB */ +#define SIGILL 4 +#define SIGTRAP 5 +#define SIGBUS 7 +#define SIGFPE 8 +#define SIGSEGV 11 +#define SIGSTKFLT 16 + + .globl gdbmach_nocode_sigfpe +gdbmach_nocode_sigfpe: + pushl $SIGFPE + jmp gdbmach_interrupt + + .globl gdbmach_nocode_sigtrap +gdbmach_nocode_sigtrap: + pushl $SIGTRAP + jmp gdbmach_interrupt + + .globl gdbmach_nocode_sigstkflt +gdbmach_nocode_sigstkflt: + pushl $SIGSTKFLT + jmp gdbmach_interrupt + + .globl gdbmach_nocode_sigill +gdbmach_nocode_sigill: + pushl $SIGILL + jmp gdbmach_interrupt + + .globl gdbmach_withcode_sigbus +gdbmach_withcode_sigbus: + movl $SIGBUS, (%esp) + jmp gdbmach_interrupt + + .globl gdbmach_withcode_sigsegv +gdbmach_withcode_sigsegv: + movl $SIGSEGV, (%esp) + jmp gdbmach_interrupt + +/* When invoked, the stack contains: eflags, cs, eip, signo. */ +#define IH_OFFSET_GDB_REGS ( 0 ) +#define IH_OFFSET_GDB_EIP ( IH_OFFSET_GDB_REGS + SIZEOF_I386_REGS ) +#define IH_OFFSET_GDB_EFLAGS ( IH_OFFSET_GDB_EIP + 4 ) +#define IH_OFFSET_GDB_SEG_REGS ( IH_OFFSET_GDB_EFLAGS + SIZEOF_I386_FLAGS ) +#define IH_OFFSET_GDB_END ( IH_OFFSET_GDB_SEG_REGS + 6 * 4 ) +#define IH_OFFSET_SIGNO ( IH_OFFSET_GDB_END ) +#define IH_OFFSET_OLD_EIP ( IH_OFFSET_SIGNO + 4 ) +#define IH_OFFSET_OLD_CS ( IH_OFFSET_OLD_EIP + 4 ) +#define IH_OFFSET_OLD_EFLAGS ( IH_OFFSET_OLD_CS + 4 ) +#define IH_OFFSET_END ( IH_OFFSET_OLD_EFLAGS + 4 ) + +/* We also access the stack whilst still storing or restoring + * the register snapshot. Since ESP is in flux, we need + * special offsets. + */ +#define IH_OFFSET_FLUX_OLD_CS ( IH_OFFSET_OLD_CS - 44 ) +#define IH_OFFSET_FLUX_OLD_EFLAGS ( IH_OFFSET_OLD_EFLAGS - 40 ) +#define IH_OFFSET_FLUX_OLD_EIP ( IH_OFFSET_OLD_EIP - 36 ) +#define IH_OFFSET_FLUX_END ( IH_OFFSET_END - 20 ) +gdbmach_interrupt: + /* Store CPU state in GDB register snapshot */ + pushw $0 + pushw %gs + pushw $0 + pushw %fs + pushw $0 + pushw %es + pushw $0 + pushw %ds + pushw $0 + pushw %ss + pushw $0 + pushw IH_OFFSET_FLUX_OLD_CS + 2(%esp) + pushl IH_OFFSET_FLUX_OLD_EFLAGS(%esp) + pushl IH_OFFSET_FLUX_OLD_EIP(%esp) + pushl %edi + pushl %esi + pushl %ebp + leal IH_OFFSET_FLUX_END(%esp), %edi + pushl %edi /* old ESP */ + pushl %ebx + pushl %edx + pushl %ecx + pushl %eax + + /* Switch to virtual addressing */ + call _intr_to_virt + + /* Call GDB stub exception handler */ + pushl %esp + pushl (IH_OFFSET_SIGNO + 4)(%esp) + call gdbmach_handler + addl $8, %esp + + /* Copy register snapshot to new stack and switch to new stack */ + movl %esp, %esi + movl (IH_OFFSET_GDB_SEG_REGS + 4)(%esp), %eax + movl %eax, %es + movl (IH_OFFSET_GDB_REGS + 16)(%esp), %edi + subl $IH_OFFSET_END, %edi + movl $(IH_OFFSET_END / 4), %ecx + pushl %edi + ss rep movsl + popl %edi + movl %eax, %ss + movl %edi, %esp + + /* Restore CPU state from GDB register snapshot */ + popl %eax + popl %ecx + popl %edx + popl %ebx + popl %ebp /* Skip %esp: already loaded */ + popl %ebp + popl %esi + popl %edi + popl IH_OFFSET_FLUX_OLD_EIP(%esp) + popl IH_OFFSET_FLUX_OLD_EFLAGS(%esp) + popl IH_OFFSET_FLUX_OLD_CS(%esp) + popl %ds /* Skip %ss: already loaded */ + popl %ds + popl %es + popl %fs + popl %gs + + addl $4, %esp /* drop signo */ + iret |