diff options
| author | Bruce Evans <bde@FreeBSD.org> | 1995-08-15 19:23:33 +0000 |
|---|---|---|
| committer | Bruce Evans <bde@FreeBSD.org> | 1995-08-15 19:23:33 +0000 |
| commit | a722b904d7291701b49c992d12d445486dfb5dd5 (patch) | |
| tree | 971c2acb9ffabc8078c02bc03881c5aea469391f /sys | |
| parent | d897bfb95069b38dfb23386ab9eb82f4f396c13d (diff) | |
Notes
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/amd64/amd64/exception.S | 14 | ||||
| -rw-r--r-- | sys/amd64/amd64/exception.s | 14 | ||||
| -rw-r--r-- | sys/i386/i386/exception.s | 14 |
3 files changed, 39 insertions, 3 deletions
diff --git a/sys/amd64/amd64/exception.S b/sys/amd64/amd64/exception.S index be6cfb3d3e5c..e0e7b3c68631 100644 --- a/sys/amd64/amd64/exception.S +++ b/sys/amd64/amd64/exception.S @@ -30,7 +30,7 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * $Id: exception.s,v 1.8.2.1 1995/06/05 00:22:02 davidg Exp $ + * $Id: exception.s,v 1.9 1995/06/11 19:31:13 rgrimes Exp $ */ #include "npx.h" /* NNPX */ @@ -175,7 +175,19 @@ calltrap: FAKE_MCOUNT(_btrap) /* init "from" _btrap -> calltrap */ incl _cnt+V_TRAP orl $SWI_AST_MASK,_cpl + + /* + * Fake a call frame: point %ebp at a 2 element array consisting + * of { trappee's %ebp, trappee's %eip }. The stack frame is in + * the wrong order for this, but the trappee's %ebp is fortunately + * followed by junk which we can overwrite with the trappee's %eip. + */ + movl TF_EIP(%esp),%eax + movl %eax,TF_ISP(%esp) + lea TF_EBP(%esp),%ebp + call _trap + /* * There was no place to save the cpl so we have to recover it * indirectly. For traps from user mode it was 0, and for traps diff --git a/sys/amd64/amd64/exception.s b/sys/amd64/amd64/exception.s index be6cfb3d3e5c..e0e7b3c68631 100644 --- a/sys/amd64/amd64/exception.s +++ b/sys/amd64/amd64/exception.s @@ -30,7 +30,7 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * $Id: exception.s,v 1.8.2.1 1995/06/05 00:22:02 davidg Exp $ + * $Id: exception.s,v 1.9 1995/06/11 19:31:13 rgrimes Exp $ */ #include "npx.h" /* NNPX */ @@ -175,7 +175,19 @@ calltrap: FAKE_MCOUNT(_btrap) /* init "from" _btrap -> calltrap */ incl _cnt+V_TRAP orl $SWI_AST_MASK,_cpl + + /* + * Fake a call frame: point %ebp at a 2 element array consisting + * of { trappee's %ebp, trappee's %eip }. The stack frame is in + * the wrong order for this, but the trappee's %ebp is fortunately + * followed by junk which we can overwrite with the trappee's %eip. + */ + movl TF_EIP(%esp),%eax + movl %eax,TF_ISP(%esp) + lea TF_EBP(%esp),%ebp + call _trap + /* * There was no place to save the cpl so we have to recover it * indirectly. For traps from user mode it was 0, and for traps diff --git a/sys/i386/i386/exception.s b/sys/i386/i386/exception.s index be6cfb3d3e5c..e0e7b3c68631 100644 --- a/sys/i386/i386/exception.s +++ b/sys/i386/i386/exception.s @@ -30,7 +30,7 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * $Id: exception.s,v 1.8.2.1 1995/06/05 00:22:02 davidg Exp $ + * $Id: exception.s,v 1.9 1995/06/11 19:31:13 rgrimes Exp $ */ #include "npx.h" /* NNPX */ @@ -175,7 +175,19 @@ calltrap: FAKE_MCOUNT(_btrap) /* init "from" _btrap -> calltrap */ incl _cnt+V_TRAP orl $SWI_AST_MASK,_cpl + + /* + * Fake a call frame: point %ebp at a 2 element array consisting + * of { trappee's %ebp, trappee's %eip }. The stack frame is in + * the wrong order for this, but the trappee's %ebp is fortunately + * followed by junk which we can overwrite with the trappee's %eip. + */ + movl TF_EIP(%esp),%eax + movl %eax,TF_ISP(%esp) + lea TF_EBP(%esp),%ebp + call _trap + /* * There was no place to save the cpl so we have to recover it * indirectly. For traps from user mode it was 0, and for traps |