ShuriZma
/
xemu
mirror of https://github.com/xemu-project/xemu.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

ppc: Add software breakpoint support 

This patch allow insert/remove software breakpoint.

When QEMU is not able to handle debug exception then we inject
program exception to guest because for software breakpoint QEMU
uses a ehpriv-1 instruction;
So there cannot be any reason that we are in qemu with exit reason
KVM_EXIT_DEBUG  for guest set debug exception, only possibility is
guest executed ehpriv-1 privilege instruction and that's why we are
injecting program exception.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
[agraf: make deflect comment booke/book3s agnostic]
Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
Bharat Bhushan 2014-07-14 14:45:38 +05:30 committed by Alexander Graf
parent c371c2e3e0
commit 8a0548f94e
1 changed files with 79 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

93
target-ppc/kvm.c
View File

@ -1275,6 +1275,75 @@ static int kvmppc_handle_dcr_write(CPUPPCState *env, uint32_t dcrn, uint32_t dat
return 0;
}
int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)
{
/* Mixed endian case is not handled */
uint32_t sc = debug_inst_opcode;
if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn,
sizeof(sc), 0) ||
cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&sc, sizeof(sc), 1)) {
return -EINVAL;
}
return 0;
}
int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)
{
uint32_t sc;
if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&sc, sizeof(sc), 0) ||
sc != debug_inst_opcode ||
cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn,
sizeof(sc), 1)) {
return -EINVAL;
}
return 0;
}
void kvm_arch_update_guest_debug(CPUState *cs, struct kvm_guest_debug *dbg)
{
/* Software Breakpoint updates */
if (kvm_sw_breakpoints_active(cs)) {
dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP;
}
}
static int kvm_handle_debug(PowerPCCPU *cpu, struct kvm_run *run)
{
CPUState *cs = CPU(cpu);
CPUPPCState *env = &cpu->env;
struct kvm_debug_exit_arch *arch_info = &run->debug.arch;
int handle = 0;
if (kvm_find_sw_breakpoint(cs, arch_info->address)) {
handle = 1;
} else {
/* QEMU is not able to handle debug exception, so inject
* program exception to guest;
* Yes program exception NOT debug exception !!
* For software breakpoint QEMU uses a privileged instruction;
* So there cannot be any reason that we are here for guest
* set debug exception, only possibility is guest executed a
* privileged / illegal instruction and that's why we are
* injecting a program interrupt.
*/
cpu_synchronize_state(cs);
/* env->nip is PC, so increment this by 4 to use
* ppc_cpu_do_interrupt(), which set srr0 = env->nip - 4.
*/
env->nip += 4;
cs->exception_index = POWERPC_EXCP_PROGRAM;
env->error_code = POWERPC_EXCP_INVAL;
ppc_cpu_do_interrupt(cs);
}
return handle;
}
int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
{
PowerPCCPU *cpu = POWERPC_CPU(cs);
@ -1315,6 +1384,16 @@ int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
ret = 0;
break;
case KVM_EXIT_DEBUG:
DPRINTF("handle debug exception\n");
if (kvm_handle_debug(cpu, run)) {
ret = EXCP_DEBUG;
break;
}
/* re-enter, this exception was guest-internal */
ret = 0;
break;
default:
fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason);
ret = -1;
@ -2007,16 +2086,6 @@ void kvm_arch_init_irq_routing(KVMState *s)
{
}
int kvm_arch_insert_sw_breakpoint(CPUState *cpu, struct kvm_sw_breakpoint *bp)
{
return -EINVAL;
}
int kvm_arch_remove_sw_breakpoint(CPUState *cpu, struct kvm_sw_breakpoint *bp)
{
return -EINVAL;
}
int kvm_arch_insert_hw_breakpoint(target_ulong addr, target_ulong len, int type)
{
return -EINVAL;
@ -2031,10 +2100,6 @@ void kvm_arch_remove_all_hw_breakpoints(void)
{
}
void kvm_arch_update_guest_debug(CPUState *cpu, struct kvm_guest_debug *dbg)
{
}
struct kvm_get_htab_buf {
struct kvm_get_htab_header header;
/*