[src/trunk]: src/sys/arch/powerpc/ibm4xx Treat trap instruction from userland...

[rin <rin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/52baad0f4009
branches:  trunk
changeset: 935986:52baad0f4009
user:      rin <rin%NetBSD.org@localhost>
date:      Wed Jul 15 08:48:40 2020 +0000

description:
Treat trap instruction from userland correctly in EXC_PGM handler;
raise SIGTRAP with TRAP_BRKPT instead of SIGILL.

diffstat:

 sys/arch/powerpc/ibm4xx/trap.c |  51 +++++++++++++++++++++++++----------------
 1 files changed, 31 insertions(+), 20 deletions(-)

diffs (75 lines):

diff -r 01f22fa47d84 -r 52baad0f4009 sys/arch/powerpc/ibm4xx/trap.c
--- a/sys/arch/powerpc/ibm4xx/trap.c    Wed Jul 15 08:29:07 2020 +0000
+++ b/sys/arch/powerpc/ibm4xx/trap.c    Wed Jul 15 08:48:40 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: trap.c,v 1.83 2020/07/06 10:41:43 rin Exp $    */
+/*     $NetBSD: trap.c,v 1.84 2020/07/15 08:48:40 rin Exp $    */
 
 /*
  * Copyright 2001 Wasabi Systems, Inc.
@@ -69,7 +69,7 @@
 #define        __UFETCHSTORE_PRIVATE
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.83 2020/07/06 10:41:43 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.84 2020/07/15 08:48:40 rin Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ddb.h"
@@ -309,27 +309,38 @@
                break;
 
        case EXC_PGM|EXC_USER:
-               /*
-                * Illegal insn:
-                *
-                * let's try to see if its FPU and can be emulated.
-                */
                curcpu()->ci_data.cpu_ntrap++;
-               pcb = lwp_getpcb(l);
+
+               KSI_INIT_TRAP(&ksi);
+               ksi.ksi_trap = EXC_PGM;
+               ksi.ksi_addr = (void *)tf->tf_srr0;
 
-               if (__predict_false(!fpu_used_p(l))) {
-                       memset(&pcb->pcb_fpu, 0, sizeof(pcb->pcb_fpu));
-                       fpu_mark_used(l);
-               }
+               if (tf->tf_esr & ESR_PTR) {
+sigtrap:
+                       if (p->p_raslist != NULL &&
+                           ras_lookup(p, (void *)tf->tf_srr0) != (void *) -1) {
+                               tf->tf_srr1 += 4;
+                               break;
+                       }
+                       ksi.ksi_code = TRAP_BRKPT;
+                       ksi.ksi_signo = SIGTRAP;
+               } else {
+                       pcb = lwp_getpcb(l);
 
-               if (fpu_emulate(tf, &pcb->pcb_fpu, &ksi)) {
-                       if (ksi.ksi_signo == 0) /* was emulated */
-                               break;
-               } else {
-                       ksi.ksi_signo = SIGILL;
-                       ksi.ksi_code = ILL_ILLOPC;
-                       ksi.ksi_trap = EXC_PGM;
-                       ksi.ksi_addr = (void *)tf->tf_srr0;
+                       if (__predict_false(!fpu_used_p(l))) {
+                               memset(&pcb->pcb_fpu, 0, sizeof(pcb->pcb_fpu));
+                               fpu_mark_used(l);
+                       }
+
+                       if (fpu_emulate(tf, &pcb->pcb_fpu, &ksi)) {
+                               if (ksi.ksi_signo == 0) /* was emulated */
+                                       break;
+                               else if (ksi.ksi_signo == SIGTRAP)
+                                       goto sigtrap;   /* XXX H/W bug? */
+                       } else {
+                               ksi.ksi_code = ILL_ILLOPC;
+                               ksi.ksi_signo = SIGILL;
+                       }
                }
 
                trapsignal(l, &ksi);