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commit 72fef4f85513d200ca6b986b0bcc5c608142a1d6
parent 4ed974f5ea8cbb6ee296782d94d83d8edbc92026
Author: rsc <rsc>
Date:   Sun, 16 Jul 2006 02:09:45 +0000

Don't kill process when inside kernel.

Diffstat:
Mtrap.c | 13++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/trap.c b/trap.c @@ -70,11 +70,18 @@ trap(struct Trapframe *tf) lapic_timerintr(); if(cpus[cpu()].nlock) panic("timer interrupt while holding a lock"); + if((read_eflags() & FL_IF) == 0) + panic("timer interrupt but interrupts now disabled"); if(cp){ - if((read_eflags() & FL_IF) == 0) - panic("timer interrupt but interrupts now disabled"); - if(cp->killed) + // 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.) + if((tf->tf_cs&3) == 3 && cp->killed) proc_exit(); + + // Force process to give up CPU and let others run. if(cp->state == RUNNING) yield(); }