diff options
| -rw-r--r-- | sys/src/9/pc64/l.s | 53 | ||||
| -rw-r--r-- | sys/src/9/pc64/trap.c | 25 |
2 files changed, 41 insertions, 37 deletions
diff --git a/sys/src/9/pc64/l.s b/sys/src/9/pc64/l.s index 40233a768..fe3de017b 100644 --- a/sys/src/9/pc64/l.s +++ b/sys/src/9/pc64/l.s @@ -686,15 +686,20 @@ f3: TEXT touser(SB), 1, $-4 CLI SWAPGS - MOVQ $UDSEL, AX + + MOVW $UDSEL, AX MOVW AX, DS MOVW AX, ES + + MOVW $NULLSEL, AX MOVW AX, FS MOVW AX, GS - MOVQ $(UTZERO+0x28), CX /* ip */ - MOVQ $0x200, R11 /* flags */ + MOVL $0, RMACH + MOVL $0, RUSER + MOVQ $(UTZERO+0x28), CX /* ip */ + MOVL $0x200, R11 /* flags */ MOVQ RARG, SP /* sp */ BYTE $0x48; SYSRET /* SYSRETQ */ @@ -703,45 +708,55 @@ TEXT touser(SB), 1, $-4 */ TEXT syscallentry(SB), 1, $-4 SWAPGS - BYTE $0x65; MOVQ 0, RMACH /* m-> (MOVQ GS:0x0, R15) */ - MOVQ 16(RMACH), RUSER /* m->proc */ + BYTE $0x65; MOVQ 0, AX /* m-> (MOVQ GS:0x0, AX) */ + MOVQ 16(AX), BX /* m->proc */ MOVQ SP, R13 - MOVQ 16(RUSER), SP /* m->proc->kstack */ + MOVQ 16(BX), SP /* m->proc->kstack */ ADDQ $KSTACK, SP + PUSHQ $UDSEL /* old stack segment */ PUSHQ R13 /* old sp */ PUSHQ R11 /* old flags */ PUSHQ $UESEL /* old code segment */ PUSHQ CX /* old ip */ - SUBQ $(17*8), SP /* unsaved registers */ - PUSHQ RARG /* system call number */ + SUBQ $(16+16*8), SP /* unsaved registers */ MOVW $UDSEL, (15*8+0)(SP) MOVW ES, (15*8+2)(SP) MOVW FS, (15*8+4)(SP) MOVW GS, (15*8+6)(SP) + MOVQ RMACH, (14*8)(SP) + MOVQ RUSER, (13*8)(SP) + + MOVQ RARG, (6*8)(SP) /* system call number */ + + MOVQ AX, RMACH /* m */ + MOVQ BX, RUSER /* up */ + MOVQ SP, RARG - PUSHQ SP /* Ureg* */ + PUSHQ SP CALL syscall(SB) TEXT forkret(SB), 1, $-4 - MOVQ 8(SP), AX /* Ureg.ax */ - MOVQ (8+6*8)(SP), BP /* Ureg.bp */ - ADDQ $(16*8), SP /* registers + arguments */ + MOVQ 8(SP), AX + ADDQ $(8+13*8), SP /* unsaved registers */ CLI SWAPGS - MOVW 0(SP), DS - MOVW 2(SP), ES - MOVW 4(SP), FS - MOVW 6(SP), GS - MOVQ 24(SP), CX /* ip */ - MOVQ 40(SP), R11 /* flags */ + MOVW 22(SP), GS + MOVW 20(SP), FS + MOVW 18(SP), ES + MOVW 16(SP), DS + + MOVQ 8(SP), RMACH + MOVQ 0(SP), RUSER - MOVQ 48(SP), SP /* sp */ + MOVQ 40(SP), CX /* ip */ + MOVQ 56(SP), R11 /* flags */ + MOVQ 64(SP), SP /* sp */ BYTE $0x48; SYSRET /* SYSRETQ */ diff --git a/sys/src/9/pc64/trap.c b/sys/src/9/pc64/trap.c index 2c2001115..6f6f95f96 100644 --- a/sys/src/9/pc64/trap.c +++ b/sys/src/9/pc64/trap.c @@ -686,7 +686,7 @@ syscall(Ureg* ureg) up->dbgreg = ureg; sp = ureg->sp; - scallnr = ureg->ax; + scallnr = ureg->bp; /* RARG */ up->scallnr = scallnr; spllo(); @@ -735,13 +735,6 @@ syscall(Ureg* ureg) up->errlab[i].sp, up->errlab[i].pc); panic("error stack"); } - - /* - * Put return value in frame. On the x86 the syscall is - * just another trap and the return value from syscall is - * ignored. On other machines the return value is put into - * the results register by caller of syscall. - */ ureg->ax = ret; if(0){ @@ -902,12 +895,8 @@ noted(Ureg* ureg, ulong arg0) pexit("Suicide", 0); } - /* don't let user change system flags */ - nureg->flags = (ureg->flags & ~0xCD5) | (nureg->flags & 0xCD5); - nureg->cs |= 3; - nureg->ss |= 3; - - memmove(ureg, nureg, sizeof(Ureg)); + /* don't let user change system flags or segment registers */ + setregisters(ureg, (char*)ureg, (char*)nureg, sizeof(Ureg)); switch(arg0){ case NCONT: @@ -965,6 +954,7 @@ execregs(uintptr entry, ulong ssize, ulong nargs) ureg->cs = UESEL; ureg->ss = ureg->ds = ureg->es = UDSEL; ureg->fs = ureg->gs = NULLSEL; + ureg->r14 = ureg->r15 = 0; /* extern user registers */ return (uintptr)USTKTOP-sizeof(Tos); /* address of kernel/user shared data */ } @@ -981,7 +971,7 @@ userpc(void) } /* This routine must save the values of registers the user is not permitted - * to write from devproc and then restore the saved values before returning. + * to write from devproc and noted() and then restore the saved values before returning. */ void setregisters(Ureg* ureg, char* pureg, char* uva, int n) @@ -995,7 +985,7 @@ setregisters(Ureg* ureg, char* pureg, char* uva, int n) if(ureg->fs != UDSEL) ureg->fs = NULLSEL; if(ureg->gs != UDSEL) - ureg->gs = 0; + ureg->gs = NULLSEL; ureg->flags = (ureg->flags & 0x00ff) | (flags & 0xff00); ureg->pc &= UADDRMASK; } @@ -1063,8 +1053,7 @@ dbgpc(Proc *p) Ureg *ureg; ureg = p->dbgreg; - if(ureg == 0) + if(ureg == nil) return 0; - return ureg->pc; } |