target/s390x: Implement s390_cpu_record_sigsegv

Move the masking of the address from cpu_loop into
s390_cpu_record_sigsegv -- this is governed by hw, not linux.
This does mean we have to raise our own exception, rather
than return to the fallback.

Use maperr to choose between PGM_PROTECTION and PGM_ADDRESSING.
Use the appropriate si_code for each in cpu_loop.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2021-09-18 10:34:30 -07:00
parent db9aab5783
commit c8e7fef102
4 changed files with 31 additions and 19 deletions

View File

@ -24,8 +24,6 @@
#include "cpu_loop-common.h"
#include "signal-common.h"
/* s390x masks the fault address it reports in si_addr for SIGSEGV and SIGBUS */
#define S390X_FAIL_ADDR_MASK -4096LL
static int get_pgm_data_si_code(int dxc_code)
{
@ -111,12 +109,13 @@ void cpu_loop(CPUS390XState *env)
n = TARGET_ILL_ILLOPC;
goto do_signal_pc;
case PGM_PROTECTION:
force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_ACCERR,
env->__excp_addr);
break;
case PGM_ADDRESSING:
sig = TARGET_SIGSEGV;
/* XXX: check env->error_code */
n = TARGET_SEGV_MAPERR;
addr = env->__excp_addr & S390X_FAIL_ADDR_MASK;
goto do_signal;
force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MAPERR,
env->__excp_addr);
break;
case PGM_EXECUTE:
case PGM_SPECIFICATION:
case PGM_SPECIAL_OP:

View File

@ -266,9 +266,11 @@ static void s390_cpu_reset_full(DeviceState *dev)
static const struct TCGCPUOps s390_tcg_ops = {
.initialize = s390x_translate_init,
.tlb_fill = s390_cpu_tlb_fill,
#if !defined(CONFIG_USER_ONLY)
#ifdef CONFIG_USER_ONLY
.record_sigsegv = s390_cpu_record_sigsegv,
#else
.tlb_fill = s390_cpu_tlb_fill,
.cpu_exec_interrupt = s390_cpu_exec_interrupt,
.do_interrupt = s390_cpu_do_interrupt,
.debug_excp_handler = s390x_cpu_debug_excp_handler,

View File

@ -270,13 +270,20 @@ ObjectClass *s390_cpu_class_by_name(const char *name);
void s390x_cpu_debug_excp_handler(CPUState *cs);
void s390_cpu_do_interrupt(CPUState *cpu);
bool s390_cpu_exec_interrupt(CPUState *cpu, int int_req);
bool s390_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr);
void s390x_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
MMUAccessType access_type, int mmu_idx,
uintptr_t retaddr) QEMU_NORETURN;
#ifdef CONFIG_USER_ONLY
void s390_cpu_record_sigsegv(CPUState *cs, vaddr address,
MMUAccessType access_type,
bool maperr, uintptr_t retaddr);
#else
bool s390_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr);
#endif
/* fpu_helper.c */
uint32_t set_cc_nz_f32(float32 v);

View File

@ -89,16 +89,20 @@ void s390_cpu_do_interrupt(CPUState *cs)
cs->exception_index = -1;
}
bool s390_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr)
void s390_cpu_record_sigsegv(CPUState *cs, vaddr address,
MMUAccessType access_type,
bool maperr, uintptr_t retaddr)
{
S390CPU *cpu = S390_CPU(cs);
trigger_pgm_exception(&cpu->env, PGM_ADDRESSING);
/* On real machines this value is dropped into LowMem. Since this
is userland, simply put this someplace that cpu_loop can find it. */
cpu->env.__excp_addr = address;
trigger_pgm_exception(&cpu->env, maperr ? PGM_ADDRESSING : PGM_PROTECTION);
/*
* On real machines this value is dropped into LowMem. Since this
* is userland, simply put this someplace that cpu_loop can find it.
* S390 only gives the page of the fault, not the exact address.
* C.f. the construction of TEC in mmu_translate().
*/
cpu->env.__excp_addr = address & TARGET_PAGE_MASK;
cpu_loop_exit_restore(cs, retaddr);
}