diff options
Diffstat (limited to 'trapasm.S')
| -rw-r--r-- | trapasm.S | 11 |
1 files changed, 6 insertions, 5 deletions
@@ -22,7 +22,7 @@ alltraps: push %rbx push %rax - cmpw $KCSEG, 32(%rsp) # compare to saved cs + cmpw $KCSEG, 144(%rsp) # compare to saved cs jz 1f swapgs @@ -33,7 +33,7 @@ alltraps: .globl trapret trapret: cli - cmpw $KCSEG, 32(%rsp) # compare to saved cs + cmpw $KCSEG, 144(%rsp) # compare to saved cs jz 1f swapgs @@ -72,12 +72,12 @@ sysentry: # Build trap frame. movq %rax, %rsp movq %gs:0, %rax // restore rax - // push usp - push $0 + // push usp to make a valid trapframe + push $(UDSEG|0x3) push %gs:8 // safe eflags and eip push %r11 - push $UCSEG + push $(UCSEG|0x3) push %rcx // push errno and trapno to make stack look like a trap push $0 @@ -130,6 +130,7 @@ sysexit: add $(5*8), %rsp # discard trapnum, errorcode, rip, cs and rflags mov (%rsp),%rsp # switch to the user stack + # there are two more values on the stack, but we don't care about them swapgs sysretq |