From 08f87f769b595151be1afeff53e144f543faa614 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Wed, 06 Dec 2023 09:51:13 +0000
Subject: [PATCH] add dts config
---
kernel/arch/x86/mm/kaslr.c | 109 +++++++++++++++---------------------------------------
1 files changed, 31 insertions(+), 78 deletions(-)
diff --git a/kernel/arch/x86/mm/kaslr.c b/kernel/arch/x86/mm/kaslr.c
index bfe7692..6e6b397 100644
--- a/kernel/arch/x86/mm/kaslr.c
+++ b/kernel/arch/x86/mm/kaslr.c
@@ -23,9 +23,9 @@
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/random.h>
+#include <linux/memblock.h>
+#include <linux/pgtable.h>
-#include <asm/pgalloc.h>
-#include <asm/pgtable.h>
#include <asm/setup.h>
#include <asm/kaslr.h>
@@ -58,15 +58,6 @@
static inline unsigned long get_padding(struct kaslr_memory_region *region)
{
return (region->size_tb << TB_SHIFT);
-}
-
-/*
- * Apply no randomization if KASLR was disabled at boot or if KASAN
- * is enabled. KASAN shadow mappings rely on regions being PGD aligned.
- */
-static inline bool kaslr_memory_enabled(void)
-{
- return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN);
}
/* Initialize base and padding for each memory region randomized with KASLR */
@@ -133,10 +124,7 @@
*/
entropy = remain_entropy / (ARRAY_SIZE(kaslr_regions) - i);
prandom_bytes_state(&rand_state, &rand, sizeof(rand));
- if (pgtable_l5_enabled())
- entropy = (rand % (entropy + 1)) & P4D_MASK;
- else
- entropy = (rand % (entropy + 1)) & PUD_MASK;
+ entropy = (rand % (entropy + 1)) & PUD_MASK;
vaddr += entropy;
*kaslr_regions[i].base = vaddr;
@@ -145,84 +133,49 @@
* randomization alignment.
*/
vaddr += get_padding(&kaslr_regions[i]);
- if (pgtable_l5_enabled())
- vaddr = round_up(vaddr + 1, P4D_SIZE);
- else
- vaddr = round_up(vaddr + 1, PUD_SIZE);
+ vaddr = round_up(vaddr + 1, PUD_SIZE);
remain_entropy -= entropy;
}
}
-static void __meminit init_trampoline_pud(void)
+void __meminit init_trampoline_kaslr(void)
{
- unsigned long paddr, paddr_next;
+ pud_t *pud_page_tramp, *pud, *pud_tramp;
+ p4d_t *p4d_page_tramp, *p4d, *p4d_tramp;
+ unsigned long paddr, vaddr;
pgd_t *pgd;
- pud_t *pud_page, *pud_page_tramp;
- int i;
pud_page_tramp = alloc_low_page();
+ /*
+ * There are two mappings for the low 1MB area, the direct mapping
+ * and the 1:1 mapping for the real mode trampoline:
+ *
+ * Direct mapping: virt_addr = phys_addr + PAGE_OFFSET
+ * 1:1 mapping: virt_addr = phys_addr
+ */
paddr = 0;
- pgd = pgd_offset_k((unsigned long)__va(paddr));
- pud_page = (pud_t *) pgd_page_vaddr(*pgd);
+ vaddr = (unsigned long)__va(paddr);
+ pgd = pgd_offset_k(vaddr);
- for (i = pud_index(paddr); i < PTRS_PER_PUD; i++, paddr = paddr_next) {
- pud_t *pud, *pud_tramp;
- unsigned long vaddr = (unsigned long)__va(paddr);
+ p4d = p4d_offset(pgd, vaddr);
+ pud = pud_offset(p4d, vaddr);
- pud_tramp = pud_page_tramp + pud_index(paddr);
- pud = pud_page + pud_index(vaddr);
- paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
+ pud_tramp = pud_page_tramp + pud_index(paddr);
+ *pud_tramp = *pud;
- *pud_tramp = *pud;
- }
-
- set_pgd(&trampoline_pgd_entry,
- __pgd(_KERNPG_TABLE | __pa(pud_page_tramp)));
-}
-
-static void __meminit init_trampoline_p4d(void)
-{
- unsigned long paddr, paddr_next;
- pgd_t *pgd;
- p4d_t *p4d_page, *p4d_page_tramp;
- int i;
-
- p4d_page_tramp = alloc_low_page();
-
- paddr = 0;
- pgd = pgd_offset_k((unsigned long)__va(paddr));
- p4d_page = (p4d_t *) pgd_page_vaddr(*pgd);
-
- for (i = p4d_index(paddr); i < PTRS_PER_P4D; i++, paddr = paddr_next) {
- p4d_t *p4d, *p4d_tramp;
- unsigned long vaddr = (unsigned long)__va(paddr);
+ if (pgtable_l5_enabled()) {
+ p4d_page_tramp = alloc_low_page();
p4d_tramp = p4d_page_tramp + p4d_index(paddr);
- p4d = p4d_page + p4d_index(vaddr);
- paddr_next = (paddr & P4D_MASK) + P4D_SIZE;
- *p4d_tramp = *p4d;
+ set_p4d(p4d_tramp,
+ __p4d(_KERNPG_TABLE | __pa(pud_page_tramp)));
+
+ set_pgd(&trampoline_pgd_entry,
+ __pgd(_KERNPG_TABLE | __pa(p4d_page_tramp)));
+ } else {
+ set_pgd(&trampoline_pgd_entry,
+ __pgd(_KERNPG_TABLE | __pa(pud_page_tramp)));
}
-
- set_pgd(&trampoline_pgd_entry,
- __pgd(_KERNPG_TABLE | __pa(p4d_page_tramp)));
-}
-
-/*
- * Create PGD aligned trampoline table to allow real mode initialization
- * of additional CPUs. Consume only 1 low memory page.
- */
-void __meminit init_trampoline(void)
-{
-
- if (!kaslr_memory_enabled()) {
- init_trampoline_default();
- return;
- }
-
- if (pgtable_l5_enabled())
- init_trampoline_p4d();
- else
- init_trampoline_pud();
}
--
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