[src/trunk]: src/sys/arch/usermode/usermode Add SIGILL handler, doing nothing...

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

details:   https://anonhg.NetBSD.org/src/rev/735bef9f1e0d
branches:  trunk
changeset: 769215:735bef9f1e0d
user:      reinoud <reinoud%NetBSD.org@localhost>
date:      Sat Sep 03 15:33:56 2011 +0000

description:
Add SIGILL handler, doing nothing than printing out details.
Move the address check to be done later so pmap and uvm have their go first.

Also some minor cosmetic fixes

diffstat:

 sys/arch/usermode/usermode/trap.c |  102 ++++++++++++++++++++++++++++++-------
 1 files changed, 83 insertions(+), 19 deletions(-)

diffs (167 lines):

diff -r db51c89a3f51 -r 735bef9f1e0d sys/arch/usermode/usermode/trap.c
--- a/sys/arch/usermode/usermode/trap.c Sat Sep 03 15:00:27 2011 +0000
+++ b/sys/arch/usermode/usermode/trap.c Sat Sep 03 15:33:56 2011 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: trap.c,v 1.19 2011/09/03 15:00:28 jmcneill Exp $ */
+/* $NetBSD: trap.c,v 1.20 2011/09/03 15:33:56 reinoud Exp $ */
 
 /*-
  * Copyright (c) 2011 Reinoud Zandijk <reinoud%netbsd.org@localhost>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.19 2011/09/03 15:00:28 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.20 2011/09/03 15:33:56 reinoud Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -52,6 +52,8 @@
 /* forwards and externals */
 void setup_signal_handlers(void);
 static void mem_access_handler(int sig, siginfo_t *info, void *ctx);
+static void illegal_instruction_handler(int sig, siginfo_t *info, void *ctx);
+extern int errno;
 
 bool pmap_fault(pmap_t pmap, vaddr_t va, vm_prot_t *atype);
 
@@ -75,8 +77,14 @@
                panic("couldn't register SIGSEGV handler : %d",
                    thunk_geterrno());
        if (thunk_sigaction(SIGBUS, &sa, NULL) == -1)
-               panic("couldn't register SIGBUS handler : %d",
-                   thunk_geterrno());
+               panic("couldn't register SIGBUS handler : %d", thunk_geterrno());
+
+       sigemptyset(&sa.sa_mask);
+       sa.sa_flags = SA_RESTART | SA_SIGINFO | SA_ONSTACK;
+       sa.sa_sigaction = illegal_instruction_handler;
+       if (thunk_sigaction(SIGILL, &sa, NULL) == -1)
+               panic("couldn't register SIGILL handler : %d", thunk_geterrno());
+
        if ((sigstk.ss_sp = thunk_malloc(SIGSTKSZ)) == NULL)
                panic("can't allocate signal stack space\n");
        sigstk.ss_size  = SIGSTKSZ;
@@ -119,7 +127,7 @@
 
 #if 0
                va = (vaddr_t) info->si_addr;
-               printf("trap lwp = %p pid = %d lid = %d, va = %p\n",
+               printf("mem trap lwp = %p pid = %d lid = %d, va = %p\n",
                    curlwp,
                    curlwp->l_proc->p_pid,
                    curlwp->l_lid,
@@ -130,21 +138,16 @@
                printf("\tsi_signo = %d\n", info->si_signo);
                printf("\tsi_errno = %d\n", info->si_errno);
                printf("\tsi_code  = %d\n", info->si_code);
-               if (info->si_code == SEGV_MAPERR) {
+               if (info->si_code == SEGV_MAPERR)
                        printf("\t\tSEGV_MAPERR\n");
-               }
-               if (info->si_code == SEGV_ACCERR) {
+               if (info->si_code == SEGV_ACCERR)
                        printf("\t\tSEGV_ACCERR\n");
-               }
-               if (info->si_code == BUS_ADRALN) {
+               if (info->si_code == BUS_ADRALN)
                        printf("\t\tBUS_ADRALN\n");
-               }
-               if (info->si_code == BUS_ADRERR) {
+               if (info->si_code == BUS_ADRERR)
                        printf("\t\tBUS_ADRERR\n");
-               }
-               if (info->si_code == BUS_OBJERR) {
+               if (info->si_code == BUS_OBJERR)
                        printf("\t\tBUS_OBJERR\n");
-               }
                printf("\tsi_addr = %p\n", info->si_addr);
                printf("\tsi_trap = %d\n", info->si_trap);
 #endif
@@ -152,10 +155,6 @@
                va = (vaddr_t) info->si_addr;
                va = trunc_page(va);
 
-               /* sanity */
-               if ((va < VM_MIN_ADDRESS) || (va >= VM_MAX_ADDRESS))
-                       panic("peeing outside the box!");
-
                kmem = 1;
                vm_map = kernel_map;
                if ((va >= VM_MIN_ADDRESS) && (va < VM_MAXUSER_ADDRESS)) {
@@ -173,6 +172,14 @@
                        pcb->pcb_onfault = onfault;
                }
 
+               /* sanity */
+               if ((va < VM_MIN_ADDRESS) || (va >= VM_MAX_ADDRESS))
+                       panic("peeing outside the box!");
+
+               /* extra debug for now */
+               if (va == 0)
+                       panic("NULL deref\n");
+
 #if 0
        if (old_old_va)
                thunk_pwrite(debug_fh, (void *) old_old_va, PAGE_SIZE, old_old_va);
@@ -210,3 +217,60 @@
        }
 }
 
+static void
+illegal_instruction_handler(int sig, siginfo_t *info, void *ctx)
+{
+       static volatile int recurse = 0;
+       struct proc *p;
+       struct lwp *l;
+       struct pcb *pcb;
+       vaddr_t va;
+
+       recurse++;
+       if (recurse > 1)
+               printf("enter trap recursion level %d\n", recurse);
+       if (info->si_signo == SIGILL) {
+               l = curlwp;
+               p = l->l_proc;
+               pcb = lwp_getpcb(l);
+
+#if 1
+               va = (vaddr_t) info->si_addr;
+               printf("illegal instruction trap lwp = %p pid = %d lid = %d, va = %p\n",
+                   curlwp,
+                   curlwp->l_proc->p_pid,
+                   curlwp->l_lid,
+                   (void *) va);
+#endif
+#if 1
+               printf("SIGILL!\n");
+               printf("\tsi_signo = %d\n", info->si_signo);
+               printf("\tsi_errno = %d\n", info->si_errno);
+               printf("\tsi_code  = %d\n", info->si_code);
+               if (info->si_code == ILL_ILLOPC)
+                       printf("\t\tIllegal opcode");
+               if (info->si_code == ILL_ILLOPN)
+                       printf("\t\tIllegal operand");
+               if (info->si_code == ILL_ILLADR)
+                       printf("\t\tIllegal addressing mode");
+               if (info->si_code == ILL_ILLTRP)
+                       printf("\t\tIllegal trap");
+               if (info->si_code == ILL_PRVOPC)
+                       printf("\t\tPrivileged opcode");
+               if (info->si_code == ILL_PRVREG)
+                       printf("\t\tPrivileged register");
+               if (info->si_code == ILL_COPROC)
+                       printf("\t\tCoprocessor error");
+               if (info->si_code == ILL_BADSTK)
+                       printf("\t\tInternal stack error");
+               printf("\tsi_addr = %p\n", info->si_addr);
+               printf("\tsi_trap = %d\n", info->si_trap);
+#endif
+
+               if (recurse > 1)
+                       printf("leaving trap recursion level %d\n", recurse);
+               recurse--;
+
+               panic("illegal instruction encountered\n");
+       }
+}