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-rw-r--r--arch/x86/kernel/entry_32.S47
-rw-r--r--arch/x86/kernel/entry_64.S16
-rw-r--r--arch/x86/kernel/head_32.S223
-rw-r--r--arch/x86/kernel/head_64.S80
-rw-r--r--arch/x86/kernel/test_rodata.c10
5 files changed, 208 insertions, 168 deletions
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index 7b784f4..01ccf9b 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -56,6 +56,7 @@
#include <asm/irq_vectors.h>
#include <asm/cpufeature.h>
#include <asm/alternative-asm.h>
+#include <asm/asm.h>
/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
#include <linux/elf-em.h>
@@ -151,10 +152,8 @@
.pushsection .fixup, "ax"
99: movl $0, (%esp)
jmp 98b
-.section __ex_table, "a"
- .align 4
- .long 98b, 99b
.popsection
+ _ASM_EXTABLE(98b,99b)
.endm
.macro PTGS_TO_GS
@@ -164,10 +163,8 @@
.pushsection .fixup, "ax"
99: movl $0, PT_GS(%esp)
jmp 98b
-.section __ex_table, "a"
- .align 4
- .long 98b, 99b
.popsection
+ _ASM_EXTABLE(98b,99b)
.endm
.macro GS_TO_REG reg
@@ -249,12 +246,10 @@
jmp 2b
6: movl $0, (%esp)
jmp 3b
-.section __ex_table, "a"
- .align 4
- .long 1b, 4b
- .long 2b, 5b
- .long 3b, 6b
.popsection
+ _ASM_EXTABLE(1b,4b)
+ _ASM_EXTABLE(2b,5b)
+ _ASM_EXTABLE(3b,6b)
POP_GS_EX
.endm
@@ -415,10 +410,7 @@ sysenter_past_esp:
jae syscall_fault
1: movl (%ebp),%ebp
movl %ebp,PT_EBP(%esp)
-.section __ex_table,"a"
- .align 4
- .long 1b,syscall_fault
-.previous
+ _ASM_EXTABLE(1b,syscall_fault)
GET_THREAD_INFO(%ebp)
@@ -485,10 +477,8 @@ sysexit_audit:
.pushsection .fixup,"ax"
2: movl $0,PT_FS(%esp)
jmp 1b
-.section __ex_table,"a"
- .align 4
- .long 1b,2b
.popsection
+ _ASM_EXTABLE(1b,2b)
PTGS_TO_GS_EX
ENDPROC(ia32_sysenter_target)
@@ -543,10 +533,7 @@ ENTRY(iret_exc)
pushl $do_iret_error
jmp error_code
.previous
-.section __ex_table,"a"
- .align 4
- .long irq_return,iret_exc
-.previous
+ _ASM_EXTABLE(irq_return,iret_exc)
CFI_RESTORE_STATE
ldt_ss:
@@ -901,10 +888,7 @@ END(device_not_available)
#ifdef CONFIG_PARAVIRT
ENTRY(native_iret)
iret
-.section __ex_table,"a"
- .align 4
- .long native_iret, iret_exc
-.previous
+ _ASM_EXTABLE(native_iret, iret_exc)
END(native_iret)
ENTRY(native_irq_enable_sysexit)
@@ -1093,13 +1077,10 @@ ENTRY(xen_failsafe_callback)
movl %eax,16(%esp)
jmp 4b
.previous
-.section __ex_table,"a"
- .align 4
- .long 1b,6b
- .long 2b,7b
- .long 3b,8b
- .long 4b,9b
-.previous
+ _ASM_EXTABLE(1b,6b)
+ _ASM_EXTABLE(2b,7b)
+ _ASM_EXTABLE(3b,8b)
+ _ASM_EXTABLE(4b,9b)
ENDPROC(xen_failsafe_callback)
BUILD_INTERRUPT3(xen_hvm_callback_vector, XEN_HVM_EVTCHN_CALLBACK,
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index cdc79b5..320852d 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -55,6 +55,7 @@
#include <asm/paravirt.h>
#include <asm/ftrace.h>
#include <asm/percpu.h>
+#include <asm/asm.h>
#include <linux/err.h>
/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
@@ -900,18 +901,12 @@ restore_args:
irq_return:
INTERRUPT_RETURN
-
- .section __ex_table, "a"
- .quad irq_return, bad_iret
- .previous
+ _ASM_EXTABLE(irq_return, bad_iret)
#ifdef CONFIG_PARAVIRT
ENTRY(native_iret)
iretq
-
- .section __ex_table,"a"
- .quad native_iret, bad_iret
- .previous
+ _ASM_EXTABLE(native_iret, bad_iret)
#endif
.section .fixup,"ax"
@@ -1181,10 +1176,7 @@ gs_change:
CFI_ENDPROC
END(native_load_gs_index)
- .section __ex_table,"a"
- .align 8
- .quad gs_change,bad_gs
- .previous
+ _ASM_EXTABLE(gs_change,bad_gs)
.section .fixup,"ax"
/* running with kernelgs */
bad_gs:
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index ce0be7c..463c979 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -21,6 +21,7 @@
#include <asm/msr-index.h>
#include <asm/cpufeature.h>
#include <asm/percpu.h>
+#include <asm/nops.h>
/* Physical address */
#define pa(X) ((X) - __PAGE_OFFSET)
@@ -363,28 +364,23 @@ default_entry:
pushl $0
popfl
-#ifdef CONFIG_SMP
- cmpb $0, ready
- jnz checkCPUtype
-#endif /* CONFIG_SMP */
-
/*
* start system 32-bit setup. We need to re-do some of the things done
* in 16-bit mode for the "real" operations.
*/
- call setup_idt
-
-checkCPUtype:
-
- movl $-1,X86_CPUID # -1 for no CPUID initially
-
+ movl setup_once_ref,%eax
+ andl %eax,%eax
+ jz 1f # Did we do this already?
+ call *%eax
+1:
+
/* check if it is 486 or 386. */
/*
* XXX - this does a lot of unnecessary setup. Alignment checks don't
* apply at our cpl of 0 and the stack ought to be aligned already, and
* we don't need to preserve eflags.
*/
-
+ movl $-1,X86_CPUID # -1 for no CPUID initially
movb $3,X86 # at least 386
pushfl # push EFLAGS
popl %eax # get EFLAGS
@@ -450,21 +446,6 @@ is386: movl $2,%ecx # set MP
movl $(__KERNEL_PERCPU), %eax
movl %eax,%fs # set this cpu's percpu
-#ifdef CONFIG_CC_STACKPROTECTOR
- /*
- * The linker can't handle this by relocation. Manually set
- * base address in stack canary segment descriptor.
- */
- cmpb $0,ready
- jne 1f
- movl $gdt_page,%eax
- movl $stack_canary,%ecx
- movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax)
- shrl $16, %ecx
- movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax)
- movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax)
-1:
-#endif
movl $(__KERNEL_STACK_CANARY),%eax
movl %eax,%gs
@@ -473,7 +454,6 @@ is386: movl $2,%ecx # set MP
cld # gcc2 wants the direction flag cleared at all times
pushl $0 # fake return address for unwinder
- movb $1, ready
jmp *(initial_code)
/*
@@ -495,81 +475,122 @@ check_x87:
.byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */
ret
+
+#include "verify_cpu.S"
+
/*
- * setup_idt
+ * setup_once
*
- * sets up a idt with 256 entries pointing to
- * ignore_int, interrupt gates. It doesn't actually load
- * idt - that can be done only after paging has been enabled
- * and the kernel moved to PAGE_OFFSET. Interrupts
- * are enabled elsewhere, when we can be relatively
- * sure everything is ok.
+ * The setup work we only want to run on the BSP.
*
* Warning: %esi is live across this function.
*/
-setup_idt:
- lea ignore_int,%edx
- movl $(__KERNEL_CS << 16),%eax
- movw %dx,%ax /* selector = 0x0010 = cs */
- movw $0x8E00,%dx /* interrupt gate - dpl=0, present */
+__INIT
+setup_once:
+ /*
+ * Set up a idt with 256 entries pointing to ignore_int,
+ * interrupt gates. It doesn't actually load idt - that needs
+ * to be done on each CPU. Interrupts are enabled elsewhere,
+ * when we can be relatively sure everything is ok.
+ */
- lea idt_table,%edi
- mov $256,%ecx
-rp_sidt:
+ movl $idt_table,%edi
+ movl $early_idt_handlers,%eax
+ movl $NUM_EXCEPTION_VECTORS,%ecx
+1:
movl %eax,(%edi)
- movl %edx,4(%edi)
+ movl %eax,4(%edi)
+ /* interrupt gate, dpl=0, present */
+ movl $(0x8E000000 + __KERNEL_CS),2(%edi)
+ addl $9,%eax
addl $8,%edi
- dec %ecx
- jne rp_sidt
+ loop 1b
-.macro set_early_handler handler,trapno
- lea \handler,%edx
+ movl $256 - NUM_EXCEPTION_VECTORS,%ecx
+ movl $ignore_int,%edx
movl $(__KERNEL_CS << 16),%eax
- movw %dx,%ax
+ movw %dx,%ax /* selector = 0x0010 = cs */
movw $0x8E00,%dx /* interrupt gate - dpl=0, present */
- lea idt_table,%edi
- movl %eax,8*\trapno(%edi)
- movl %edx,8*\trapno+4(%edi)
-.endm
+2:
+ movl %eax,(%edi)
+ movl %edx,4(%edi)
+ addl $8,%edi
+ loop 2b
- set_early_handler handler=early_divide_err,trapno=0
- set_early_handler handler=early_illegal_opcode,trapno=6
- set_early_handler handler=early_protection_fault,trapno=13
- set_early_handler handler=early_page_fault,trapno=14
+#ifdef CONFIG_CC_STACKPROTECTOR
+ /*
+ * Configure the stack canary. The linker can't handle this by
+ * relocation. Manually set base address in stack canary
+ * segment descriptor.
+ */
+ movl $gdt_page,%eax
+ movl $stack_canary,%ecx
+ movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax)
+ shrl $16, %ecx
+ movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax)
+ movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax)
+#endif
+ andl $0,setup_once_ref /* Once is enough, thanks */
ret
-early_divide_err:
- xor %edx,%edx
- pushl $0 /* fake errcode */
- jmp early_fault
+ENTRY(early_idt_handlers)
+ # 36(%esp) %eflags
+ # 32(%esp) %cs
+ # 28(%esp) %eip
+ # 24(%rsp) error code
+ i = 0
+ .rept NUM_EXCEPTION_VECTORS
+ .if (EXCEPTION_ERRCODE_MASK >> i) & 1
+ ASM_NOP2
+ .else
+ pushl $0 # Dummy error code, to make stack frame uniform
+ .endif
+ pushl $i # 20(%esp) Vector number
+ jmp early_idt_handler
+ i = i + 1
+ .endr
+ENDPROC(early_idt_handlers)
+
+ /* This is global to keep gas from relaxing the jumps */
+ENTRY(early_idt_handler)
+ cld
+ cmpl $2,%ss:early_recursion_flag
+ je hlt_loop
+ incl %ss:early_recursion_flag
-early_illegal_opcode:
- movl $6,%edx
- pushl $0 /* fake errcode */
- jmp early_fault
+ push %eax # 16(%esp)
+ push %ecx # 12(%esp)
+ push %edx # 8(%esp)
+ push %ds # 4(%esp)
+ push %es # 0(%esp)
+ movl $(__KERNEL_DS),%eax
+ movl %eax,%ds
+ movl %eax,%es
-early_protection_fault:
- movl $13,%edx
- jmp early_fault
+ cmpl $(__KERNEL_CS),32(%esp)
+ jne 10f
-early_page_fault:
- movl $14,%edx
- jmp early_fault
+ leal 28(%esp),%eax # Pointer to %eip
+ call early_fixup_exception
+ andl %eax,%eax
+ jnz ex_entry /* found an exception entry */
-early_fault:
- cld
+10:
#ifdef CONFIG_PRINTK
- pusha
- movl $(__KERNEL_DS),%eax
- movl %eax,%ds
- movl %eax,%es
- cmpl $2,early_recursion_flag
- je hlt_loop
- incl early_recursion_flag
+ xorl %eax,%eax
+ movw %ax,2(%esp) /* clean up the segment values on some cpus */
+ movw %ax,6(%esp)
+ movw %ax,34(%esp)
+ leal 40(%esp),%eax
+ pushl %eax /* %esp before the exception */
+ pushl %ebx
+ pushl %ebp
+ pushl %esi
+ pushl %edi
movl %cr2,%eax
pushl %eax
- pushl %edx /* trapno */
+ pushl (20+6*4)(%esp) /* trapno */
pushl $fault_msg
call printk
#endif
@@ -578,6 +599,17 @@ hlt_loop:
hlt
jmp hlt_loop
+ex_entry:
+ pop %es
+ pop %ds
+ pop %edx
+ pop %ecx
+ pop %eax
+ addl $8,%esp /* drop vector number and error code */
+ decl %ss:early_recursion_flag
+ iret
+ENDPROC(early_idt_handler)
+
/* This is the default interrupt "handler" :-) */
ALIGN
ignore_int:
@@ -611,13 +643,18 @@ ignore_int:
popl %eax
#endif
iret
+ENDPROC(ignore_int)
+__INITDATA
+ .align 4
+early_recursion_flag:
+ .long 0
-#include "verify_cpu.S"
-
- __REFDATA
-.align 4
+__REFDATA
+ .align 4
ENTRY(initial_code)
.long i386_start_kernel
+ENTRY(setup_once_ref)
+ .long setup_once
/*
* BSS section
@@ -670,22 +707,19 @@ ENTRY(initial_page_table)
ENTRY(stack_start)
.long init_thread_union+THREAD_SIZE
-early_recursion_flag:
- .long 0
-
-ready: .byte 0
-
+__INITRODATA
int_msg:
.asciz "Unknown interrupt or fault at: %p %p %p\n"
fault_msg:
/* fault info: */
.ascii "BUG: Int %d: CR2 %p\n"
-/* pusha regs: */
- .ascii " EDI %p ESI %p EBP %p ESP %p\n"
- .ascii " EBX %p EDX %p ECX %p EAX %p\n"
+/* regs pushed in early_idt_handler: */
+ .ascii " EDI %p ESI %p EBP %p EBX %p\n"
+ .ascii " ESP %p ES %p DS %p\n"
+ .ascii " EDX %p ECX %p EAX %p\n"
/* fault frame: */
- .ascii " err %p EIP %p CS %p flg %p\n"
+ .ascii " vec %p err %p EIP %p CS %p flg %p\n"
.ascii "Stack: %p %p %p %p %p %p %p %p\n"
.ascii " %p %p %p %p %p %p %p %p\n"
.asciz " %p %p %p %p %p %p %p %p\n"
@@ -699,6 +733,7 @@ fault_msg:
* segment size, and 32-bit linear address value:
*/
+ .data
.globl boot_gdt_descr
.globl idt_descr
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 40f4eb3..7a40f24 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -19,12 +19,15 @@
#include <asm/cache.h>
#include <asm/processor-flags.h>
#include <asm/percpu.h>
+#include <asm/nops.h>
#ifdef CONFIG_PARAVIRT
#include <asm/asm-offsets.h>
#include <asm/paravirt.h>
+#define GET_CR2_INTO(reg) GET_CR2_INTO_RAX ; movq %rax, reg
#else
-#define GET_CR2_INTO_RCX movq %cr2, %rcx
+#define GET_CR2_INTO(reg) movq %cr2, reg
+#define INTERRUPT_RETURN iretq
#endif
/* we are not able to switch in one step to the final KERNEL ADDRESS SPACE
@@ -270,36 +273,56 @@ bad_address:
jmp bad_address
.section ".init.text","ax"
-#ifdef CONFIG_EARLY_PRINTK
.globl early_idt_handlers
early_idt_handlers:
+ # 104(%rsp) %rflags
+ # 96(%rsp) %cs
+ # 88(%rsp) %rip
+ # 80(%rsp) error code
i = 0
.rept NUM_EXCEPTION_VECTORS
- movl $i, %esi
+ .if (EXCEPTION_ERRCODE_MASK >> i) & 1
+ ASM_NOP2
+ .else
+ pushq $0 # Dummy error code, to make stack frame uniform
+ .endif
+ pushq $i # 72(%rsp) Vector number
jmp early_idt_handler
i = i + 1
.endr
-#endif
ENTRY(early_idt_handler)
-#ifdef CONFIG_EARLY_PRINTK
+ cld
+
cmpl $2,early_recursion_flag(%rip)
jz 1f
incl early_recursion_flag(%rip)
- GET_CR2_INTO_RCX
- movq %rcx,%r9
- xorl %r8d,%r8d # zero for error code
- movl %esi,%ecx # get vector number
- # Test %ecx against mask of vectors that push error code.
- cmpl $31,%ecx
- ja 0f
- movl $1,%eax
- salq %cl,%rax
- testl $0x27d00,%eax
- je 0f
- popq %r8 # get error code
-0: movq 0(%rsp),%rcx # get ip
- movq 8(%rsp),%rdx # get cs
+
+ pushq %rax # 64(%rsp)
+ pushq %rcx # 56(%rsp)
+ pushq %rdx # 48(%rsp)
+ pushq %rsi # 40(%rsp)
+ pushq %rdi # 32(%rsp)
+ pushq %r8 # 24(%rsp)
+ pushq %r9 # 16(%rsp)
+ pushq %r10 # 8(%rsp)
+ pushq %r11 # 0(%rsp)
+
+ cmpl $__KERNEL_CS,96(%rsp)
+ jne 10f
+
+ leaq 88(%rsp),%rdi # Pointer to %rip
+ call early_fixup_exception
+ andl %eax,%eax
+ jnz 20f # Found an exception entry
+
+10:
+#ifdef CONFIG_EARLY_PRINTK
+ GET_CR2_INTO(%r9) # can clobber any volatile register if pv
+ movl 80(%rsp),%r8d # error code
+ movl 72(%rsp),%esi # vector number
+ movl 96(%rsp),%edx # %cs
+ movq 88(%rsp),%rcx # %rip
xorl %eax,%eax
leaq early_idt_msg(%rip),%rdi
call early_printk
@@ -308,17 +331,32 @@ ENTRY(early_idt_handler)
call dump_stack
#ifdef CONFIG_KALLSYMS
leaq early_idt_ripmsg(%rip),%rdi
- movq 0(%rsp),%rsi # get rip again
+ movq 40(%rsp),%rsi # %rip again
call __print_symbol
#endif
#endif /* EARLY_PRINTK */
1: hlt
jmp 1b
-#ifdef CONFIG_EARLY_PRINTK
+20: # Exception table entry found
+ popq %r11
+ popq %r10
+ popq %r9
+ popq %r8
+ popq %rdi
+ popq %rsi
+ popq %rdx
+ popq %rcx
+ popq %rax
+ addq $16,%rsp # drop vector number and error code
+ decl early_recursion_flag(%rip)
+ INTERRUPT_RETURN
+
+ .balign 4
early_recursion_flag:
.long 0
+#ifdef CONFIG_EARLY_PRINTK
early_idt_msg:
.asciz "PANIC: early exception %02lx rip %lx:%lx error %lx cr2 %lx\n"
early_idt_ripmsg:
diff --git a/arch/x86/kernel/test_rodata.c b/arch/x86/kernel/test_rodata.c
index c29e235..b79133a 100644
--- a/arch/x86/kernel/test_rodata.c
+++ b/arch/x86/kernel/test_rodata.c
@@ -12,6 +12,7 @@
#include <linux/module.h>
#include <asm/cacheflush.h>
#include <asm/sections.h>
+#include <asm/asm.h>
int rodata_test(void)
{
@@ -42,14 +43,7 @@ int rodata_test(void)
".section .fixup,\"ax\"\n"
"2: jmp 1b\n"
".previous\n"
- ".section __ex_table,\"a\"\n"
- " .align 16\n"
-#ifdef CONFIG_X86_32
- " .long 0b,2b\n"
-#else
- " .quad 0b,2b\n"
-#endif
- ".previous"
+ _ASM_EXTABLE(0b,2b)
: [rslt] "=r" (result)
: [rodata_test] "r" (&rodata_test_data), [zero] "r" (0UL)
);
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