:: commit de3c7eed679fde24060434dcc369ea22836d9654
stivale2: Implement PMRs
diff --git a/stage23/lib/elf.c b/stage23/lib/elf.c
index 7eabee7c..5b7e3913 100644
--- a/stage23/lib/elf.c
+++ b/stage23/lib/elf.c
@@ -8,7 +8,7 @@
#include <mm/pmm.h>
#include <fs/file.h>
-#define KASLR_SLIDE_BITMASK ((uintptr_t)0x3ffff000)
+#define KASLR_SLIDE_BITMASK ((uintptr_t)0x8ffff000)
#define PT_LOAD 0x00000001
#define PT_INTERP 0x00000003
@@ -420,7 +420,7 @@ int elf64_load(uint8_t *elf, uint64_t *entry_point, uint64_t *top, uint64_t *_sl
again:
if (kaslr)
- slide = rand64() & KASLR_SLIDE_BITMASK;
+ slide = (rand64() & KASLR_SLIDE_BITMASK) & (min_align - 1);
final:
if (top)
diff --git a/stage23/protos/stivale.32.c b/stage23/protos/stivale.32.c
index e104aae0..ad9c1a23 100644
--- a/stage23/protos/stivale.32.c
+++ b/stage23/protos/stivale.32.c
@@ -4,7 +4,7 @@
#include <mm/vmm.h>
__attribute__((noreturn)) void stivale_spinup_32(
- int bits, bool level5pg, uint32_t pagemap_top_lv,
+ int bits, bool level5pg, bool enable_nx, uint32_t pagemap_top_lv,
uint32_t entry_point_lo, uint32_t entry_point_hi,
uint32_t stivale_struct_lo, uint32_t stivale_struct_hi,
uint32_t stack_lo, uint32_t stack_hi) {
@@ -15,6 +15,16 @@ __attribute__((noreturn)) void stivale_spinup_32(
};
if (bits == 64) {
+ if (enable_nx) {
+ asm volatile (
+ "movl $0xc0000080, %%ecx\n\t"
+ "rdmsr\n\t"
+ "btsl $11, %%eax\n\t"
+ "wrmsr\n\t"
+ ::: "eax", "ecx", "edx", "memory"
+ );
+ }
+
if (level5pg) {
// Enable CR4.LA57
asm volatile (
diff --git a/stage23/protos/stivale.c b/stage23/protos/stivale.c
index 347d1a3f..aa2b0284 100644
--- a/stage23/protos/stivale.c
+++ b/stage23/protos/stivale.c
@@ -295,7 +295,7 @@ void stivale_load(char *config, char *cmdline) {
stivale_spinup(bits, want_5lv, &pagemap,
entry_point, REPORTED_ADDR((uint64_t)(uintptr_t)&stivale_struct),
- stivale_hdr.stack);
+ stivale_hdr.stack, false);
}
pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range *ranges, size_t ranges_count) {
@@ -307,20 +307,16 @@ pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range
for (uint64_t i = 0; i < 0x80000000; i += 0x200000) {
map_page(pagemap, 0xffffffff80000000 + i, i, 0x03, true);
}
-
- // Sub 2MiB mappings
- for (uint64_t i = 0; i < 0x200000; i += 0x1000) {
- if (!(i == 0 && unmap_null))
- map_page(pagemap, i, i, 0x03, false);
- map_page(pagemap, higher_half_base + i, i, 0x03, false);
- }
} else {
for (size_t i = 0; i < ranges_count; i++) {
uint64_t virt = ranges[i].base;
uint64_t phys = virt;
- if (phys & ((uint64_t)1 << 63))
+ if (phys & ((uint64_t)1 << 63)) {
phys -= FIXED_HIGHER_HALF_OFFSET_64;
+ } else {
+ panic("stivale2: Protected memory ranges are only supported for higher half kernels");
+ }
uint64_t pf = VMM_FLAG_PRESENT |
(ranges[i].permissions & ELF_PF_X ? 0 : VMM_FLAG_NOEXEC) |
@@ -332,6 +328,13 @@ pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range
}
}
+ // Sub 2MiB mappings
+ for (uint64_t i = 0; i < 0x200000; i += 0x1000) {
+ if (!(i == 0 && unmap_null))
+ map_page(pagemap, i, i, 0x03, false);
+ map_page(pagemap, higher_half_base + i, i, 0x03, false);
+ }
+
// Map 2MiB to 4GiB at higher half base and 0
for (uint64_t i = 0x200000; i < 0x100000000; i += 0x200000) {
map_page(pagemap, i, i, 0x03, true);
@@ -382,7 +385,8 @@ __attribute__((noreturn)) void stivale_spinup_32(
__attribute__((noreturn)) void stivale_spinup(
int bits, bool level5pg, pagemap_t *pagemap,
- uint64_t entry_point, uint64_t _stivale_struct, uint64_t stack) {
+ uint64_t entry_point, uint64_t _stivale_struct, uint64_t stack,
+ bool enable_nx) {
#if bios == 1
if (bits == 64) {
// If we're going 64, we might as well call this BIOS interrupt
@@ -395,11 +399,15 @@ __attribute__((noreturn)) void stivale_spinup(
}
#endif
+ if (enable_nx) {
+ vmm_assert_nx();
+ }
+
pic_mask_all();
pic_flush();
common_spinup(stivale_spinup_32, 9,
- bits, level5pg, (uint32_t)(uintptr_t)pagemap->top_level,
+ bits, level5pg, enable_nx, (uint32_t)(uintptr_t)pagemap->top_level,
(uint32_t)entry_point, (uint32_t)(entry_point >> 32),
(uint32_t)_stivale_struct, (uint32_t)(_stivale_struct >> 32),
(uint32_t)stack, (uint32_t)(stack >> 32));
diff --git a/stage23/protos/stivale.h b/stage23/protos/stivale.h
index b0ea8809..5379dc3b 100644
--- a/stage23/protos/stivale.h
+++ b/stage23/protos/stivale.h
@@ -13,6 +13,7 @@ bool stivale_load_by_anchor(void **_anchor, const char *magic,
pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range *ranges, size_t ranges_count);
__attribute__((noreturn)) void stivale_spinup(
int bits, bool level5pg, pagemap_t *pagemap,
- uint64_t entry_point, uint64_t stivale_struct, uint64_t stack);
+ uint64_t entry_point, uint64_t stivale_struct, uint64_t stack,
+ bool enable_nx);
#endif
diff --git a/stage23/protos/stivale2.c b/stage23/protos/stivale2.c
index 2cc8077b..9b7c75d4 100644
--- a/stage23/protos/stivale2.c
+++ b/stage23/protos/stivale2.c
@@ -81,6 +81,9 @@ void stivale2_load(char *config, char *cmdline, bool pxe, void *efi_system_table
uint64_t slide = 0;
uint64_t entry_point = 0;
+ struct elf_range *ranges;
+ uint64_t ranges_count;
+
uint8_t *kernel = freadall(kernel_file, STIVALE2_MMAP_BOOTLOADER_RECLAIMABLE);
int bits = elf_bits(kernel);
bool loaded_by_anchor = false;
@@ -99,6 +102,8 @@ void stivale2_load(char *config, char *cmdline, bool pxe, void *efi_system_table
loaded_by_anchor = true;
}
+ bool want_pmrs = false;
+
int ret = 0;
switch (bits) {
case 64: {
@@ -114,9 +119,25 @@ void stivale2_load(char *config, char *cmdline, bool pxe, void *efi_system_table
}
if (!loaded_by_anchor) {
+ ret = elf64_load_section(kernel, &stivale2_hdr, ".stivale2hdr",
+ sizeof(struct stivale2_header), 0);
+ if (ret) {
+ goto failed_to_load_header_section;
+ }
+
+ if ((stivale2_hdr.flags & (1 << 2))) {
+ if (bits == 32) {
+ panic("stivale2: PMRs are not supported for 32-bit kernels");
+ } else if (loaded_by_anchor) {
+ panic("stivale2: PMRs are not supported for anchored kernels");
+ }
+ want_pmrs = true;
+ }
+
if (elf64_load(kernel, &entry_point, NULL, &slide,
STIVALE2_MMAP_KERNEL_AND_MODULES, kaslr, false,
- NULL, NULL))
+ want_pmrs ? &ranges : NULL,
+ want_pmrs ? &ranges_count : NULL))
panic("stivale2: ELF64 load failure");
ret = elf64_load_section(kernel, &stivale2_hdr, ".stivale2hdr",
@@ -142,6 +163,7 @@ void stivale2_load(char *config, char *cmdline, bool pxe, void *efi_system_table
printv("stivale2: %u-bit kernel detected\n", bits);
+failed_to_load_header_section:
switch (ret) {
case 1:
panic("stivale2: File is not a valid ELF.");
@@ -462,6 +484,25 @@ skip_modeset:;
(void)pxe;
#endif
+ //////////////////////////////////////////////
+ // Create PMRs struct tag
+ //////////////////////////////////////////////
+ {
+ if (want_pmrs) {
+ struct stivale2_struct_tag_pmrs *tag =
+ ext_mem_alloc(sizeof(struct stivale2_struct_tag_pmrs)
+ + ranges_count * sizeof(struct stivale2_pmr));
+
+ tag->tag.identifier = STIVALE2_STRUCT_TAG_PMRS_ID;
+
+ tag->entries = ranges_count;
+
+ memcpy(tag->pmrs, ranges, ranges_count * sizeof(struct stivale2_pmr));
+
+ append_tag(&stivale2_struct, (struct stivale2_tag *)tag);
+ }
+ }
+
//////////////////////////////////////////////
// Create EFI system table struct tag
//////////////////////////////////////////////
@@ -480,7 +521,9 @@ skip_modeset:;
pagemap_t pagemap = {0};
if (bits == 64)
- pagemap = stivale_build_pagemap(want_5lv, unmap_null, NULL, 0);
+ pagemap = stivale_build_pagemap(want_5lv, unmap_null,
+ want_pmrs ? ranges : NULL,
+ want_pmrs ? ranges_count : 0);
#if uefi == 1
efi_exit_boot_services();
@@ -499,7 +542,7 @@ skip_modeset:;
smp_info = init_smp(sizeof(struct stivale2_struct_tag_smp), (void **)&tag,
&cpu_count, &bsp_lapic_id,
bits == 64, want_5lv,
- pagemap, smp_hdr_tag->flags & 1);
+ pagemap, smp_hdr_tag->flags & 1, want_pmrs);
if (smp_info != NULL) {
tag->tag.identifier = STIVALE2_STRUCT_TAG_SMP_ID;
@@ -557,5 +600,5 @@ skip_modeset:;
stivale_spinup(bits, want_5lv, &pagemap, entry_point,
REPORTED_ADDR((uint64_t)(uintptr_t)&stivale2_struct),
- stivale2_hdr.stack);
+ stivale2_hdr.stack, want_pmrs);
}
diff --git a/stage23/sys/smp.c b/stage23/sys/smp.c
index 5abeb993..79f463e9 100644
--- a/stage23/sys/smp.c
+++ b/stage23/sys/smp.c
@@ -58,7 +58,7 @@ struct trampoline_passed_info {
static bool smp_start_ap(uint32_t lapic_id, struct gdtr *gdtr,
struct smp_information *info_struct,
bool longmode, bool lv5, uint32_t pagemap,
- bool x2apic) {
+ bool x2apic, bool nx) {
size_t trampoline_size = (size_t)_binary_smp_trampoline_bin_end
- (size_t)_binary_smp_trampoline_bin_start;
@@ -81,6 +81,7 @@ static bool smp_start_ap(uint32_t lapic_id, struct gdtr *gdtr,
passed_info->smp_tpl_pagemap = pagemap;
passed_info->smp_tpl_target_mode = ((uint32_t)x2apic << 2)
| ((uint32_t)lv5 << 1)
+ | ((uint32_t)nx << 3)
| (uint32_t)longmode;
passed_info->smp_tpl_gdt = *gdtr;
passed_info->smp_tpl_booted_flag = 0;
@@ -122,7 +123,8 @@ struct smp_information *init_smp(size_t header_hack_size,
bool longmode,
bool lv5,
pagemap_t pagemap,
- bool x2apic) {
+ bool x2apic,
+ bool nx) {
if (!lapic_check())
return NULL;
@@ -227,7 +229,7 @@ struct smp_information *init_smp(size_t header_hack_size,
// Try to start the AP
if (!smp_start_ap(lapic->lapic_id, &gdtr, info_struct,
longmode, lv5, (uintptr_t)pagemap.top_level,
- x2apic)) {
+ x2apic, nx)) {
print("smp: FAILED to bring-up AP\n");
continue;
}
@@ -264,7 +266,7 @@ struct smp_information *init_smp(size_t header_hack_size,
// Try to start the AP
if (!smp_start_ap(x2lapic->x2apic_id, &gdtr, info_struct,
longmode, lv5, (uintptr_t)pagemap.top_level,
- true)) {
+ true, nx)) {
print("smp: FAILED to bring-up AP\n");
continue;
}
diff --git a/stage23/sys/smp.h b/stage23/sys/smp.h
index 0e36df14..efc0f7c6 100644
--- a/stage23/sys/smp.h
+++ b/stage23/sys/smp.h
@@ -21,6 +21,7 @@ struct smp_information *init_smp(size_t header_hack_size,
bool longmode,
bool lv5,
pagemap_t pagemap,
- bool x2apic);
+ bool x2apic,
+ bool nx);
#endif
diff --git a/stage23/sys/smp_trampoline.real b/stage23/sys/smp_trampoline.real
index 86968c20..fa8b173e 100644
--- a/stage23/sys/smp_trampoline.real
+++ b/stage23/sys/smp_trampoline.real
@@ -56,6 +56,11 @@ smp_trampoline:
bts eax, 5
mov cr4, eax
+ mov ecx, 0xc0000080
+ mov eax, 0x100
+ xor edx, edx
+ wrmsr
+
test dword [ebx + passed_info.target_mode], (1 << 1)
jz .no5lv
@@ -67,11 +72,6 @@ smp_trampoline:
mov eax, dword [ebx + passed_info.pagemap]
mov cr3, eax
- mov ecx, 0xc0000080
- mov eax, 0x100
- xor edx, edx
- wrmsr
-
mov eax, cr0
bts eax, 31
mov cr0, eax
@@ -91,6 +91,16 @@ smp_trampoline:
mov gs, ax
mov ss, ax
+ mov ebx, ebx
+ test dword [rbx + passed_info.target_mode], (1 << 3)
+ jz .nonx
+
+ mov ecx, 0xc0000080
+ rdmsr
+ bts eax, 11
+ wrmsr
+
+ .nonx:
jmp parking64
bits 32
diff --git a/test/stivale2.c b/test/stivale2.c
index eef221d9..834c494c 100644
--- a/test/stivale2.c
+++ b/test/stivale2.c
@@ -42,7 +42,7 @@ __attribute__((section(".stivale2hdr"), used))
struct stivale2_header header2 = {
.entry_point = (uint64_t)stivale2_main,
.stack = (uintptr_t)stacks[0] + sizeof(stack),
- .flags = 1 << 1,
+ .flags = (1 << 1) | (1 << 2),
.tags = (uint64_t)&framebuffer_request
};
@@ -184,6 +184,15 @@ void stivale2_main(struct stivale2_struct *info) {
e9_printf("Kernel slide: %x", t->kernel_slide);
break;
}
+ case STIVALE2_STRUCT_TAG_PMRS_ID: {
+ struct stivale2_struct_tag_pmrs *t = (struct stivale2_struct_tag_pmrs *)tag;
+ e9_puts("PMRs tag:");
+ e9_printf("\t%d ranges:", t->entries);
+ for (size_t i = 0; i < t->entries; i++) {
+ e9_printf("\t\tBase: %x Length: %x Perms: %x",
+ t->pmrs[i].base, t->pmrs[i].length, t->pmrs[i].permissions);
+ }
+ }
case STIVALE2_STRUCT_TAG_SMP_ID: {
struct stivale2_struct_tag_smp *s = (struct stivale2_struct_tag_smp *)tag;
e9_puts("SMP tag:");
