diff options
| -rw-r--r-- | trap.c | 18 |
1 files changed, 6 insertions, 12 deletions
@@ -9,10 +9,8 @@ // Interrupt descriptor table (shared by all CPUs). struct gatedesc idt[256]; - extern uint vectors[]; // in vectors.S: array of 256 entry pointers - void tvinit(void) { @@ -46,8 +44,7 @@ trap(struct trapframe *tf) } // Increment nlock to make sure interrupts stay off - // during interrupt handler. Must decrement before - // returning. + // during interrupt handler. Decrement before returning. cpus[cpu()].nlock++; switch(v){ @@ -55,11 +52,9 @@ trap(struct trapframe *tf) lapic_timerintr(); cpus[cpu()].nlock--; if(cp){ - // Force process exit if it has been killed - // and the interrupt came from user space. - // (If the kernel was executing at time of interrupt, - // don't kill the process. Let the process get back - // out to its regular system call return.) + // Force process exit if it has been killed and is in user space. + // (If it is still executing in the kernel, let it keep running + // until it gets to the regular system call return.) if((tf->cs&3) == 3 && cp->killed) proc_exit(); @@ -85,14 +80,13 @@ trap(struct trapframe *tf) default: if(curproc[cpu()]) { - // assume process caused unexpected trap, - // for example by dividing by zero or dereferencing a bad pointer + // Assume process divided by zero or dereferenced null, etc. cprintf("pid %d: unhandled trap %d on cpu %d eip %x -- kill proc\n", curproc[cpu()]->pid, v, cpu(), tf->eip); proc_exit(); } - // otherwise it's our mistake + // Otherwise it's our mistake. cprintf("unexpected trap %d from cpu %d eip %x\n", v, cpu(), tf->eip); panic("trap"); } |