aarch64: set ttbr0_el1 to null for kernel thread, fixed #56

Author: equation314

bootloader/Cargo.lock

@@ -9,7 +9,7 @@ xmas-elf = "0.6.2"
 fixedvec = "0.2.3"
 
 [target.'cfg(target_arch = "aarch64")'.dependencies]
-aarch64 = { git = "https://github.com/rcore-os/aarch64", version = "2.6.1" }
+aarch64 = { git = "https://github.com/rcore-os/aarch64", version = "2.7.0" }
 bcm2837 = { git = "https://github.com/rcore-os/bcm2837", version = "1.0.0" }
 
 [build-dependencies]

bootloader/Cargo.toml

@@ -1,5 +1,5 @@
 use aarch64::addr::{PhysAddr, VirtAddr};
-use aarch64::paging::{memory_attribute::*, Page, PageTable, PageTableFlags as EF, PhysFrame};
+use aarch64::paging::{memory_attribute::*, Page, PageTable, PageTableAttribute, PageTableFlags as EF, PhysFrame};
 use aarch64::paging::{Size1GiB, Size2MiB, Size4KiB};
 use aarch64::{asm::*, barrier, regs::*};
 use bcm2837::consts::RAW_IO_BASE;
@@ -42,7 +42,7 @@ fn create_page_table(start_paddr: usize, end_paddr: usize) {
     p3.zero();
     p2.zero();
 
-    let block_flags = EF::VALID | EF::AF | EF::WRITE | EF::UXN;
+    let block_flags = EF::default_block() | EF::UXN;
     // normal memory
     for frame in PhysFrame::<Size2MiB>::range_of(start_paddr as u64, end_paddr as u64) {
         let paddr = frame.start_address();
@@ -58,10 +58,10 @@ fn create_page_table(start_paddr: usize, end_paddr: usize) {
         p2[page.p2_index()].set_block::<Size2MiB>(paddr, block_flags | EF::PXN, MairDevice::attr_value());
     }
 
-    p3[0].set_frame(frame_lvl2, EF::default(), MairNormal::attr_value());
+    p3[0].set_frame(frame_lvl2, EF::default_table(), PageTableAttribute::new(0, 0, 0));
     p3[1].set_block::<Size1GiB>(PhysAddr::new(0x4000_0000), block_flags | EF::PXN, MairDevice::attr_value());
 
-    p4[0].set_frame(frame_lvl3, EF::default(), MairNormal::attr_value());
+    p4[0].set_frame(frame_lvl3, EF::default_table(), PageTableAttribute::new(0, 0, 0));
 
     // the bootloader is still running at the lower virtual address range,
     // so the TTBR0_EL1 also needs to be set.

bootloader/src/arch/aarch64/mod.rs

@@ -86,7 +86,7 @@ aml = "0.4"
 riscv = { git = "https://github.com/rcore-os/riscv", features = ["inline-asm"] }
 
 [target.'cfg(target_arch = "aarch64")'.dependencies]
-aarch64 = { git = "https://github.com/rcore-os/aarch64", version = "2.6.1" }
+aarch64 = { git = "https://github.com/rcore-os/aarch64", version = "2.7.0" }
 bcm2837 = { git = "https://github.com/rcore-os/bcm2837", version = "1.0.0", optional = true }
 
 [target.'cfg(target_arch = "mips")'.dependencies]

kernel/Cargo.lock

@@ -2,11 +2,13 @@
 
 use crate::consts::MEMORY_OFFSET;
 use crate::memory::{init_heap, virt_to_phys, FRAME_ALLOCATOR};
+use aarch64::{paging::frame::PhysFrame, asm::ttbr_el1_write};
 use log::*;
 use rcore_memory::PAGE_SIZE;
 
 /// Memory initialization.
 pub fn init() {
+    ttbr_el1_write(0, PhysFrame::of_addr(0));
     init_frame_allocator();
     init_heap();
     info!("memory: init end");

kernel/Cargo.toml

@@ -9,7 +9,7 @@ use aarch64::paging::{
     page_table::{PageTable as Aarch64PageTable, PageTableEntry, PageTableFlags as EF},
     FrameAllocator, FrameDeallocator, Page as PageAllSizes, Size4KiB,
 };
-use aarch64::{PhysAddr, VirtAddr};
+use aarch64::PhysAddr;
 use core::mem::ManuallyDrop;
 use log::*;
 use rcore_memory::paging::*;
@@ -26,7 +26,7 @@ pub struct PageEntry(&'static mut PageTableEntry, Page);
 
 impl PageTable for PageTableImpl {
     fn map(&mut self, addr: usize, target: usize) -> &mut dyn Entry {
-        let flags = EF::default();
+        let flags = EF::default_page() | EF::PXN | EF::UXN;
         let attr = MairNormal::attr_value();
         unsafe {
             self.page_table
@@ -85,6 +85,7 @@ pub enum MMIOType {
     Unsupported = 3,
 }
 
+// TODO: software dirty bit needs to be reconsidered
 impl Entry for PageEntry {
     fn update(&mut self) {
         tlb_invalidate(self.1.start_address());
@@ -161,9 +162,11 @@ impl Entry for PageEntry {
     }
     fn set_execute(&mut self, value: bool) {
         if self.user() {
-            self.as_flags().set(EF::UXN, !value)
+            self.as_flags().set(EF::UXN, !value);
+            self.as_flags().set(EF::PXN, true);
         } else {
-            self.as_flags().set(EF::PXN, !value)
+            self.as_flags().set(EF::PXN, !value);
+            self.as_flags().set(EF::UXN, true)
         }
     }
     fn mmio(&self) -> u8 {