[src/trunk]: src/sys/arch/aarch64 - fixed a problem where hardware {break,wat...

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

details:   https://anonhg.NetBSD.org/src/rev/3c3d85c7ba64
branches:  trunk
changeset: 981411:3c3d85c7ba64
user:      ryo <ryo%NetBSD.org@localhost>
date:      Thu Mar 11 09:48:40 2021 +0000

description:
- fixed a problem where hardware {break,watch}points other than #0 could not be cleared
- hardware {break,watch}point addresses are now strictly checked

diffstat:

 sys/arch/aarch64/aarch64/db_machdep.c |  55 +++++++++++++++++++++++-----------
 sys/arch/aarch64/include/db_machdep.h |   4 +-
 2 files changed, 39 insertions(+), 20 deletions(-)

diffs (172 lines):

diff -r be993b0b3d61 -r 3c3d85c7ba64 sys/arch/aarch64/aarch64/db_machdep.c
--- a/sys/arch/aarch64/aarch64/db_machdep.c     Thu Mar 11 08:33:34 2021 +0000
+++ b/sys/arch/aarch64/aarch64/db_machdep.c     Thu Mar 11 09:48:40 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: db_machdep.c,v 1.37 2021/03/09 16:44:27 ryo Exp $ */
+/* $NetBSD: db_machdep.c,v 1.38 2021/03/11 09:48:40 ryo Exp $ */
 
 /*-
  * Copyright (c) 2014 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: db_machdep.c,v 1.37 2021/03/09 16:44:27 ryo Exp $");
+__KERNEL_RCSID(0, "$NetBSD: db_machdep.c,v 1.38 2021/03/11 09:48:40 ryo Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_compat_netbsd32.h"
@@ -699,7 +699,7 @@
                bvr = 0;
                bcr = 0;
        } else {
-               bvr = addr;
+               bvr = addr & DBGBVR_MASK;
                bcr =
                    __SHIFTIN(0, DBGBCR_BT) |
                    __SHIFTIN(0, DBGBCR_LBN) |
@@ -714,7 +714,7 @@
 }
 
 void
-aarch64_watchpoint_set(int n, vaddr_t addr, int size, int accesstype)
+aarch64_watchpoint_set(int n, vaddr_t addr, u_int size, u_int accesstype)
 {
        uint64_t wvr, wcr;
        uint32_t matchbytebit;
@@ -723,9 +723,13 @@
        if (size > 8)
                size = 8;
 
-       /* BAS must be all of whose set bits are contiguous */
+       /*
+        * It is always watched in 8byte units, and
+        * BAS is a bit field of byte offset in 8byte units.
+        */
        matchbytebit = 0xff >> (8 - size);
        matchbytebit <<= (addr & 7);
+       addr &= ~7UL;
 
        /* load, store, or both */
        accesstype &= WATCHPOINT_ACCESS_MASK;
@@ -752,24 +756,37 @@
        aarch64_set_wcr_wvr(n, wcr, wvr);
 }
 
-static void
+static int
 db_md_breakpoint_set(int n, vaddr_t addr)
 {
        if (n >= __arraycount(breakpoint_buf))
-               return;
+               return -1;
+
+       if ((addr & 3) != 0) {
+               db_printf("address must be 4bytes aligned\n");
+               return -1;
+       }
 
        breakpoint_buf[n].addr = addr;
+       return 0;
 }
 
-static void
-db_md_watchpoint_set(int n, vaddr_t addr, int size, int accesstype)
+static int
+db_md_watchpoint_set(int n, vaddr_t addr, u_int size, u_int accesstype)
 {
        if (n >= __arraycount(watchpoint_buf))
-               return;
+               return -1;
+
+       if (size != 0 && ((addr) & ~7UL) != ((addr + size - 1) & ~7UL)) {
+               db_printf(
+                   "address and size must fit within a block of 8bytes\n");
+               return -1;
+       }
 
        watchpoint_buf[n].addr = addr;
        watchpoint_buf[n].size = size;
        watchpoint_buf[n].accesstype = accesstype;
+       return 0;
 }
 
 static void
@@ -893,7 +910,7 @@
 db_md_break_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
     const char *modif)
 {
-       int i;
+       int i, rc;
        int added, cleared;
 
        if (!have_addr) {
@@ -901,7 +918,6 @@
                return;
        }
 
-       addr &= DBGBVR_MASK;
        added = -1;
        cleared = -1;
        if (0 <= addr && addr <= max_breakpoint) {
@@ -920,7 +936,9 @@
                if (cleared == -1) {
                        for (i = 0; i <= max_breakpoint; i++) {
                                if (breakpoint_buf[i].addr == 0) {
-                                       db_md_breakpoint_set(i, addr);
+                                       rc = db_md_breakpoint_set(i, addr);
+                                       if (rc != 0)
+                                               return;
                                        added = i;
                                        break;
                                }
@@ -944,16 +962,15 @@
 db_md_watch_cmd(db_expr_t addr, bool have_addr, db_expr_t count,
     const char *modif)
 {
-       int i;
+       int i, rc;
        int added, cleared;
-       int accesstype, watchsize;
+       u_int accesstype, watchsize;
 
        if (!have_addr) {
                show_watchpoints();
                return;
        }
 
-       addr &= DBGWVR_MASK;
        accesstype = watchsize = 0;
        if ((modif != NULL) && (*modif != '\0')) {
                int ch;
@@ -1003,8 +1020,10 @@
                if (cleared == -1) {
                        for (i = 0; i <= max_watchpoint; i++) {
                                if (watchpoint_buf[i].addr == 0) {
-                                       db_md_watchpoint_set(i, addr, watchsize,
-                                           accesstype);
+                                       rc = db_md_watchpoint_set(i, addr,
+                                           watchsize, accesstype);
+                                       if (rc != 0)
+                                               return;
                                        added = i;
                                        break;
                                }
diff -r be993b0b3d61 -r 3c3d85c7ba64 sys/arch/aarch64/include/db_machdep.h
--- a/sys/arch/aarch64/include/db_machdep.h     Thu Mar 11 08:33:34 2021 +0000
+++ b/sys/arch/aarch64/include/db_machdep.h     Thu Mar 11 09:48:40 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: db_machdep.h,v 1.12 2021/03/09 16:44:27 ryo Exp $ */
+/* $NetBSD: db_machdep.h,v 1.13 2021/03/11 09:48:40 ryo Exp $ */
 
 /*-
  * Copyright (c) 2014 The NetBSD Foundation, Inc.
@@ -218,7 +218,7 @@
 
 /* hardware breakpoint/watchpoint functions */
 void aarch64_breakpoint_set(int, vaddr_t);
-void aarch64_watchpoint_set(int, vaddr_t, int, int);
+void aarch64_watchpoint_set(int, vaddr_t, u_int, u_int);
 #define WATCHPOINT_ACCESS_LOAD         0x01
 #define WATCHPOINT_ACCESS_STORE                0x02
 #define WATCHPOINT_ACCESS_LOADSTORE    0x03