diff options
Diffstat (limited to 'sys/arch')
| -rw-r--r-- | sys/arch/amd64/amd64/proc_machdep.c | 23 |
1 files changed, 10 insertions, 13 deletions
diff --git a/sys/arch/amd64/amd64/proc_machdep.c b/sys/arch/amd64/amd64/proc_machdep.c index eb3866a..d2eb599 100644 --- a/sys/arch/amd64/amd64/proc_machdep.c +++ b/sys/arch/amd64/amd64/proc_machdep.c @@ -46,12 +46,12 @@ * @ip: Instruction pointer. */ int -md_td_init(struct proc *p, struct proc *parent, uintptr_t ip) +md_fork(struct proc *p, struct proc *parent, uintptr_t ip) { uintptr_t stack_base; - struct trapframe *tfp, *parent_tfp; + struct trapframe *tfp; struct pcb *pcbp; - uint8_t rpl; + uint8_t rpl = 0; int error; tfp = &p->tf; @@ -61,18 +61,15 @@ md_td_init(struct proc *p, struct proc *parent, uintptr_t ip) if ((error = pmap_new_vas(&pcbp->addrsp)) != 0) return error; + memcpy(tfp, &parent->tf, sizeof(p->tf)); + /* - * If parent is NULL, assume kernel space and zero the - * trapframe. Otherwise we can just set it up normally. + * Kernel threads cannot be on the lower half. + * If 'ip' is on the lower half, assume that it + * is a userspace program and set RPL to ring 3. */ - if (parent == NULL) { - rpl = 0; - memset(tfp, 0, sizeof(*tfp)); - } else { - parent_tfp = &parent->tf; - rpl = parent_tfp->cs & 3; - memcpy(tfp, &parent->tf, sizeof(*tfp)); - } + if (ip < VM_HIGHER_HALF) + rpl = 3; /* * RPL being 3 indicates that the parent thread is in |