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This instantly creates a page fault as we always map pages with ring 0
permissions.
This commit is contained in:
Drew Galbraith 2023-05-29 12:44:26 -07:00
parent aefb4f082b
commit 7184f527a0
7 changed files with 37 additions and 7 deletions
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16
zion/scheduler/jump_user_space.s Normal file
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@ -0,0 +1,16 @@
.global jump_user_space
// rdi - entry point, rsi - user stack
jump_user_space:
cli
mov $0x23, %ax
mov %ax, %ds
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
pushq $0x23 # ss
pushq %rsi
pushf # Can we just push 0 for flags?
pushq $0x1B # cs
pushq %rdi
iretq

15
zion/scheduler/thread.cpp
View file

@ -1,12 +1,16 @@
#include "scheduler/thread.h"
#include "common/gdt.h"
#include "debug/debug.h"
#include "loader/elf_loader.h"
#include "memory/paging_util.h"
#include "scheduler/process.h"
#include "scheduler/scheduler.h"
namespace {
extern "C" void jump_user_space(uint64_t rip, uint64_t rsp);
extern "C" void thread_init() {
asm("sti");
sched::CurrentThread().Init();
@ -36,9 +40,10 @@ Thread::Thread(Process* proc, uint64_t tid, uint64_t elf_ptr)
uint64_t Thread::pid() { return process_->id(); }
void Thread::Init() {
LoadElfProgram(elf_ptr_, 0);
while (true) {
dbgln("[%u.%u]", pid(), id_);
sched::Yield();
}
dbgln("[%u.%u]", pid(), id_);
uint64_t rip = LoadElfProgram(elf_ptr_, 0);
uint64_t rsp = 0x80000000;
EnsureResident(rsp - 1, 1);
SetRsp0(rsp0_start_);
jump_user_space(rip, rsp);
}