diff options
Diffstat (limited to 'usr/src/uts/i86pc/os/trap.c')
| -rw-r--r-- | usr/src/uts/i86pc/os/trap.c | 44 |
1 files changed, 28 insertions, 16 deletions
diff --git a/usr/src/uts/i86pc/os/trap.c b/usr/src/uts/i86pc/os/trap.c index 9a38a811a5..10034cc67f 100644 --- a/usr/src/uts/i86pc/os/trap.c +++ b/usr/src/uts/i86pc/os/trap.c @@ -386,6 +386,7 @@ trap(struct regs *rp, caddr_t addr, processorid_t cpuid) int watchcode; int watchpage; caddr_t vaddr; + int singlestep_twiddle; size_t sz; int ta; #ifdef __amd64 @@ -975,19 +976,33 @@ trap(struct regs *rp, caddr_t addr, processorid_t cpuid) * * The same thing happens for sysenter, too. */ + singlestep_twiddle = 0; + if (rp->r_pc == (uintptr_t)sys_sysenter || + rp->r_pc == (uintptr_t)brand_sys_sysenter) { + singlestep_twiddle = 1; #if defined(__amd64) - if (rp->r_pc == (uintptr_t)sys_sysenter) { /* - * Adjust the pc so that we don't execute the - * swapgs instruction at the head of the - * handler and completely confuse things. + * Since we are already on the kernel's + * %gs, on 64-bit systems the sysenter case + * needs to adjust the pc to avoid + * executing the swapgs instruction at the + * top of the handler. */ - rp->r_pc = (uintptr_t) - _sys_sysenter_post_swapgs; -#elif defined(__i386) - if (rp->r_pc == (uintptr_t)sys_call || - rp->r_pc == (uintptr_t)sys_sysenter) { + if (rp->r_pc == (uintptr_t)sys_sysenter) + rp->r_pc = (uintptr_t) + _sys_sysenter_post_swapgs; + else + rp->r_pc = (uintptr_t) + _brand_sys_sysenter_post_swapgs; +#endif + } +#if defined(__i386) + else if (rp->r_pc == (uintptr_t)sys_call || + rp->r_pc == (uintptr_t)brand_sys_call) { + singlestep_twiddle = 1; + } #endif + if (singlestep_twiddle) { rp->r_ps &= ~PS_T; /* turn off trace */ lwp->lwp_pcb.pcb_flags |= DEBUG_PENDING; cur_thread->t_post_sys = 1; @@ -1161,20 +1176,17 @@ trap(struct regs *rp, caddr_t addr, processorid_t cpuid) rp->r_ps &= ~PS_T; /* * If both NORMAL_STEP and WATCH_STEP are in effect, - * give precedence to NORMAL_STEP. If neither is set, + * give precedence to WATCH_STEP. If neither is set, * user must have set the PS_T bit in %efl; treat this * as NORMAL_STEP. */ - if ((pcb->pcb_flags & NORMAL_STEP) || - !(pcb->pcb_flags & WATCH_STEP)) { + if ((fault = undo_watch_step(&siginfo)) == 0 && + ((pcb->pcb_flags & NORMAL_STEP) || + !(pcb->pcb_flags & WATCH_STEP))) { siginfo.si_signo = SIGTRAP; siginfo.si_code = TRAP_TRACE; siginfo.si_addr = (caddr_t)rp->r_pc; fault = FLTTRACE; - if (pcb->pcb_flags & WATCH_STEP) - (void) undo_watch_step(NULL); - } else { - fault = undo_watch_step(&siginfo); } pcb->pcb_flags &= ~(NORMAL_STEP|WATCH_STEP); } else { |