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Diffstat (limited to 'arch/x86/kernel/head_64.S')
-rw-r--r--arch/x86/kernel/head_64.S50
1 files changed, 41 insertions, 9 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index a468c0a65c42..f8a8406033c3 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -321,26 +321,28 @@ bad_address:
jmp bad_address
__INIT
- .globl early_idt_handlers
-early_idt_handlers:
+ENTRY(early_idt_handler_array)
# 104(%rsp) %rflags
# 96(%rsp) %cs
# 88(%rsp) %rip
# 80(%rsp) error code
i = 0
.rept NUM_EXCEPTION_VECTORS
- .if (EXCEPTION_ERRCODE_MASK >> i) & 1
- ASM_NOP2
- .else
+ .ifeq (EXCEPTION_ERRCODE_MASK >> i) & 1
pushq $0 # Dummy error code, to make stack frame uniform
.endif
pushq $i # 72(%rsp) Vector number
- jmp early_idt_handler
+ jmp early_idt_handler_common
i = i + 1
+ .fill early_idt_handler_array + i*EARLY_IDT_HANDLER_SIZE - ., 1, 0xcc
.endr
+ENDPROC(early_idt_handler_array)
-/* This is global to keep gas from relaxing the jumps */
-ENTRY(early_idt_handler)
+early_idt_handler_common:
+ /*
+ * The stack is the hardware frame, an error code or zero, and the
+ * vector number.
+ */
cld
cmpl $2,(%rsp) # X86_TRAP_NMI
@@ -412,7 +414,7 @@ ENTRY(early_idt_handler)
is_nmi:
addq $16,%rsp # drop vector number and error code
INTERRUPT_RETURN
-ENDPROC(early_idt_handler)
+ENDPROC(early_idt_handler_common)
__INITDATA
@@ -514,8 +516,38 @@ ENTRY(phys_base)
/* This must match the first entry in level2_kernel_pgt */
.quad 0x0000000000000000
+#ifdef CONFIG_KASAN
+#define FILL(VAL, COUNT) \
+ .rept (COUNT) ; \
+ .quad (VAL) ; \
+ .endr
+
+NEXT_PAGE(kasan_zero_pte)
+ FILL(kasan_zero_page - __START_KERNEL_map + _KERNPG_TABLE, 512)
+NEXT_PAGE(kasan_zero_pmd)
+ FILL(kasan_zero_pte - __START_KERNEL_map + _KERNPG_TABLE, 512)
+NEXT_PAGE(kasan_zero_pud)
+ FILL(kasan_zero_pmd - __START_KERNEL_map + _KERNPG_TABLE, 512)
+
+#undef FILL
+#endif
+
+
#include "../../x86/xen/xen-head.S"
__PAGE_ALIGNED_BSS
NEXT_PAGE(empty_zero_page)
.skip PAGE_SIZE
+
+#ifdef CONFIG_KASAN
+/*
+ * This page used as early shadow. We don't use empty_zero_page
+ * at early stages, stack instrumentation could write some garbage
+ * to this page.
+ * Latter we reuse it as zero shadow for large ranges of memory
+ * that allowed to access, but not instrumented by kasan
+ * (vmalloc/vmemmap ...).
+ */
+NEXT_PAGE(kasan_zero_page)
+ .skip PAGE_SIZE
+#endif