diff options
| author | Aleksa Vuckovic <aleksav013@gmail.com> | 2022-11-26 00:22:10 +0100 |
|---|---|---|
| committer | Aleksa Vuckovic <aleksav013@gmail.com> | 2022-11-27 01:04:18 +0100 |
| commit | d43a3388a976a74ae109c5b8b5a31f82a16b45db (patch) | |
| tree | 51880414ee600ddfb3c7e3486c3d74beced36bfe /kernel/src/mem/paging.c | |
| parent | 5d56d1a5b4d52702eb4e4ea6f05e4b6eebf41ca8 (diff) | |
fixing issues
1) main.c: order of init (multiboot.c must be after heap & paging
because it uses heap to allocate pages for framebuffer)
2) paging.c: zeroing new pages allocated via heap
3) multiboot2.c: invalid pointer arithmetic
4) libk/string.c: check for null pointers in memcpy
5) paging: only page_lvl2 should have FLAG_HUGE
6) keyboard.c: kfree(print_buff)
Diffstat (limited to 'kernel/src/mem/paging.c')
| -rw-r--r-- | kernel/src/mem/paging.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/kernel/src/mem/paging.c b/kernel/src/mem/paging.c index 774c5d6..fd88dbc 100644 --- a/kernel/src/mem/paging.c +++ b/kernel/src/mem/paging.c @@ -2,7 +2,9 @@ #include <paging.h> #include <heap.h> +#include <libk/serial_stdio.h> #include <libk/stdio.h> +#include <libk/string.h> #include <kernel_vma.h> void load_pt_lvl4(uint64_t*); @@ -25,6 +27,7 @@ void map_addr(uint64_t virt, uint64_t phys, uint32_t flags) uint64_t* pt_lvl3 = (uint64_t*)(page_table_lvl4[pt_lvl4_i] + KERNEL_VMA); if (!((uint64_t)pt_lvl3 & FLAG_PRESENT)) { pt_lvl3 = (uint64_t*)kalloc(4096); + memset(pt_lvl3, 0, 4096); page_table_lvl4[pt_lvl4_i] = ((uint64_t)pt_lvl3 - KERNEL_VMA) | flags; } else { pt_lvl3 = (uint64_t*)((uint64_t)pt_lvl3 - (uint64_t)pt_lvl3 % 4096); @@ -33,6 +36,7 @@ void map_addr(uint64_t virt, uint64_t phys, uint32_t flags) uint64_t* pt_lvl2 = (uint64_t*)(pt_lvl3[pt_lvl3_i] + KERNEL_VMA); if (!((uint64_t)pt_lvl2 & FLAG_PRESENT)) { pt_lvl2 = (uint64_t*)kalloc(4096); + memset(pt_lvl2, 0, 4096); pt_lvl3[pt_lvl3_i] = ((uint64_t)pt_lvl2 - KERNEL_VMA) | flags; } else { pt_lvl2 = (uint64_t*)((uint64_t)pt_lvl2 - (uint64_t)pt_lvl2 % 4096); @@ -43,23 +47,22 @@ void map_addr(uint64_t virt, uint64_t phys, uint32_t flags) void init_paging(void) { - page_table_lvl4[511] = (uint64_t)page_table_lvl3 + FLAG_PRESENT + FLAG_WRITABLE + FLAG_USER - KERNEL_VMA; - page_table_lvl3[510] = (uint64_t)page_table_lvl2 + FLAG_PRESENT + FLAG_WRITABLE + FLAG_USER - KERNEL_VMA; + page_table_lvl4[511] = (uint64_t)page_table_lvl3 - KERNEL_VMA + (FLAG_PRESENT | FLAG_WRITABLE | FLAG_USER); + page_table_lvl3[510] = (uint64_t)page_table_lvl2 - KERNEL_VMA + (FLAG_PRESENT | FLAG_WRITABLE | FLAG_USER); // 16mb kernel + 32mb heap for (size_t i = 0; i < 24; i++) { - page_table_lvl2[i] = (uint64_t)0x0 + PAGE_SIZE * i + FLAG_PRESENT + FLAG_WRITABLE + FLAG_USER + FLAG_HUGE; + page_table_lvl2[i] = (uint64_t)0x0 + PAGE_SIZE * i + (FLAG_PRESENT | FLAG_WRITABLE | FLAG_USER | FLAG_HUGE); } load_pt_lvl4(page_table_lvl4); } - void page_fault(uint64_t error) { uint64_t addr; __asm__ volatile ("mov %%cr2, %0;" : "=r"(addr) : : "memory"); - map_addr(addr, addr, FLAG_PRESENT | FLAG_WRITABLE | FLAG_USER | FLAG_HUGE); - printf("address: 0x%x, error code: %d\n", addr, error); + + map_addr(addr, addr, FLAG_PRESENT | FLAG_WRITABLE | FLAG_USER); } |