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-rw-r--r--arch/x86/kernel/Makefile1
-rw-r--r--arch/x86/kernel/cpu/common.c6
-rw-r--r--arch/x86/kernel/cpu/intel.c4
-rw-r--r--arch/x86/kernel/entry_32.S3
-rw-r--r--arch/x86/kernel/entry_64.S3
-rw-r--r--arch/x86/kernel/head_32.S3
-rw-r--r--arch/x86/kernel/head_64.S4
-rw-r--r--arch/x86/kernel/kprobes/core.c54
-rw-r--r--arch/x86/kernel/kprobes/opt.c2
-rw-r--r--arch/x86/kernel/process_64.c2
-rw-r--r--arch/x86/kernel/ptrace.c10
-rw-r--r--arch/x86/kernel/syscall_32.c16
-rw-r--r--arch/x86/kernel/traps.c21
13 files changed, 95 insertions, 34 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index cdb1b70ddad0..c887cd944f0c 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_X86_32) += i386_ksyms_32.o
obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o
obj-$(CONFIG_X86_64) += mcount_64.o
obj-y += syscall_$(BITS).o vsyscall_gtod.o
+obj-$(CONFIG_IA32_EMULATION) += syscall_32.o
obj-$(CONFIG_X86_VSYSCALL_EMULATION) += vsyscall_64.o vsyscall_emu_64.o
obj-$(CONFIG_X86_ESPFIX64) += espfix_64.o
obj-$(CONFIG_SYSFS) += ksysfs.o
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index b5c8ff5e9dfc..2346c95c6ab1 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1396,6 +1396,12 @@ void cpu_init(void)
wait_for_master_cpu(cpu);
+ /*
+ * Initialize the CR4 shadow before doing anything that could
+ * try to read it.
+ */
+ cr4_init_shadow();
+
show_ucode_info_early();
printk(KERN_INFO "Initializing CPU#%d\n", cpu);
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 94d7dcb12145..50163fa9034f 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -565,8 +565,8 @@ static const struct _tlb_table intel_tlb_table[] = {
{ 0xb2, TLB_INST_4K, 64, " TLB_INST 4KByte pages, 4-way set associative" },
{ 0xb3, TLB_DATA_4K, 128, " TLB_DATA 4 KByte pages, 4-way set associative" },
{ 0xb4, TLB_DATA_4K, 256, " TLB_DATA 4 KByte pages, 4-way associative" },
- { 0xb5, TLB_INST_4K, 64, " TLB_INST 4 KByte pages, 8-way set ssociative" },
- { 0xb6, TLB_INST_4K, 128, " TLB_INST 4 KByte pages, 8-way set ssociative" },
+ { 0xb5, TLB_INST_4K, 64, " TLB_INST 4 KByte pages, 8-way set associative" },
+ { 0xb6, TLB_INST_4K, 128, " TLB_INST 4 KByte pages, 8-way set associative" },
{ 0xba, TLB_DATA_4K, 64, " TLB_DATA 4 KByte pages, 4-way associative" },
{ 0xc0, TLB_DATA_4K_4M, 8, " TLB_DATA 4 KByte and 4 MByte pages, 4-way associative" },
{ 0xc1, STLB_4K_2M, 1024, " STLB 4 KByte and 2 MByte pages, 8-way associative" },
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index b910577d1ff9..7e0323cc0b7d 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -976,6 +976,9 @@ ENTRY(xen_hypervisor_callback)
ENTRY(xen_do_upcall)
1: mov %esp, %eax
call xen_evtchn_do_upcall
+#ifndef CONFIG_PREEMPT
+ call xen_maybe_preempt_hcall
+#endif
jmp ret_from_intr
CFI_ENDPROC
ENDPROC(xen_hypervisor_callback)
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index db13655c3a2a..10074ad9ebf8 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1208,6 +1208,9 @@ ENTRY(xen_do_hypervisor_callback) # do_hypervisor_callback(struct *pt_regs)
popq %rsp
CFI_DEF_CFA_REGISTER rsp
decl PER_CPU_VAR(irq_count)
+#ifndef CONFIG_PREEMPT
+ call xen_maybe_preempt_hcall
+#endif
jmp error_exit
CFI_ENDPROC
END(xen_do_hypervisor_callback)
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index f36bd42d6f0c..d031bad9e07e 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -22,6 +22,7 @@
#include <asm/cpufeature.h>
#include <asm/percpu.h>
#include <asm/nops.h>
+#include <asm/bootparam.h>
/* Physical address */
#define pa(X) ((X) - __PAGE_OFFSET)
@@ -90,7 +91,7 @@ ENTRY(startup_32)
/* test KEEP_SEGMENTS flag to see if the bootloader is asking
us to not reload segments */
- testb $(1<<6), BP_loadflags(%esi)
+ testb $KEEP_SEGMENTS, BP_loadflags(%esi)
jnz 2f
/*
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 6fd514d9f69a..9a0919678f97 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -1,5 +1,5 @@
/*
- * linux/arch/x86_64/kernel/head.S -- start in 32bit and switch to 64bit
+ * linux/arch/x86/kernel/head_64.S -- start in 32bit and switch to 64bit
*
* Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
* Copyright (C) 2000 Pavel Machek <pavel@suse.cz>
@@ -56,7 +56,7 @@ startup_64:
* %rsi holds a physical pointer to real_mode_data.
*
* We come here either directly from a 64bit bootloader, or from
- * arch/x86_64/boot/compressed/head.S.
+ * arch/x86/boot/compressed/head_64.S.
*
* We only come here initially at boot nothing else comes here.
*
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 6a1146ea4d4d..4e3d5a9621fe 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -223,27 +223,48 @@ static unsigned long
__recover_probed_insn(kprobe_opcode_t *buf, unsigned long addr)
{
struct kprobe *kp;
+ unsigned long faddr;
kp = get_kprobe((void *)addr);
- /* There is no probe, return original address */
- if (!kp)
+ faddr = ftrace_location(addr);
+ /*
+ * Addresses inside the ftrace location are refused by
+ * arch_check_ftrace_location(). Something went terribly wrong
+ * if such an address is checked here.
+ */
+ if (WARN_ON(faddr && faddr != addr))
+ return 0UL;
+ /*
+ * Use the current code if it is not modified by Kprobe
+ * and it cannot be modified by ftrace.
+ */
+ if (!kp && !faddr)
return addr;
/*
- * Basically, kp->ainsn.insn has an original instruction.
- * However, RIP-relative instruction can not do single-stepping
- * at different place, __copy_instruction() tweaks the displacement of
- * that instruction. In that case, we can't recover the instruction
- * from the kp->ainsn.insn.
+ * Basically, kp->ainsn.insn has an original instruction.
+ * However, RIP-relative instruction can not do single-stepping
+ * at different place, __copy_instruction() tweaks the displacement of
+ * that instruction. In that case, we can't recover the instruction
+ * from the kp->ainsn.insn.
*
- * On the other hand, kp->opcode has a copy of the first byte of
- * the probed instruction, which is overwritten by int3. And
- * the instruction at kp->addr is not modified by kprobes except
- * for the first byte, we can recover the original instruction
- * from it and kp->opcode.
+ * On the other hand, in case on normal Kprobe, kp->opcode has a copy
+ * of the first byte of the probed instruction, which is overwritten
+ * by int3. And the instruction at kp->addr is not modified by kprobes
+ * except for the first byte, we can recover the original instruction
+ * from it and kp->opcode.
+ *
+ * In case of Kprobes using ftrace, we do not have a copy of
+ * the original instruction. In fact, the ftrace location might
+ * be modified at anytime and even could be in an inconsistent state.
+ * Fortunately, we know that the original code is the ideal 5-byte
+ * long NOP.
*/
- memcpy(buf, kp->addr, MAX_INSN_SIZE * sizeof(kprobe_opcode_t));
- buf[0] = kp->opcode;
+ memcpy(buf, (void *)addr, MAX_INSN_SIZE * sizeof(kprobe_opcode_t));
+ if (faddr)
+ memcpy(buf, ideal_nops[NOP_ATOMIC5], 5);
+ else
+ buf[0] = kp->opcode;
return (unsigned long)buf;
}
@@ -251,6 +272,7 @@ __recover_probed_insn(kprobe_opcode_t *buf, unsigned long addr)
* Recover the probed instruction at addr for further analysis.
* Caller must lock kprobes by kprobe_mutex, or disable preemption
* for preventing to release referencing kprobes.
+ * Returns zero if the instruction can not get recovered.
*/
unsigned long recover_probed_instruction(kprobe_opcode_t *buf, unsigned long addr)
{
@@ -285,6 +307,8 @@ static int can_probe(unsigned long paddr)
* normally used, we just go through if there is no kprobe.
*/
__addr = recover_probed_instruction(buf, addr);
+ if (!__addr)
+ return 0;
kernel_insn_init(&insn, (void *)__addr, MAX_INSN_SIZE);
insn_get_length(&insn);
@@ -333,6 +357,8 @@ int __copy_instruction(u8 *dest, u8 *src)
unsigned long recovered_insn =
recover_probed_instruction(buf, (unsigned long)src);
+ if (!recovered_insn)
+ return 0;
kernel_insn_init(&insn, (void *)recovered_insn, MAX_INSN_SIZE);
insn_get_length(&insn);
/* Another subsystem puts a breakpoint, failed to recover */
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index 0dd8d089c315..7b3b9d15c47a 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -259,6 +259,8 @@ static int can_optimize(unsigned long paddr)
*/
return 0;
recovered_insn = recover_probed_instruction(buf, addr);
+ if (!recovered_insn)
+ return 0;
kernel_insn_init(&insn, (void *)recovered_insn, MAX_INSN_SIZE);
insn_get_length(&insn);
/* Another subsystem puts a breakpoint */
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 67fcc43577d2..854b5981b327 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -207,7 +207,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
*/
if (clone_flags & CLONE_SETTLS) {
#ifdef CONFIG_IA32_EMULATION
- if (test_thread_flag(TIF_IA32))
+ if (is_ia32_task())
err = do_set_thread_area(p, -1,
(struct user_desc __user *)childregs->si, 0);
else
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index e510618b2e91..1e125817cf9f 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -364,18 +364,12 @@ static int set_segment_reg(struct task_struct *task,
case offsetof(struct user_regs_struct,cs):
if (unlikely(value == 0))
return -EIO;
-#ifdef CONFIG_IA32_EMULATION
- if (test_tsk_thread_flag(task, TIF_IA32))
- task_pt_regs(task)->cs = value;
-#endif
+ task_pt_regs(task)->cs = value;
break;
case offsetof(struct user_regs_struct,ss):
if (unlikely(value == 0))
return -EIO;
-#ifdef CONFIG_IA32_EMULATION
- if (test_tsk_thread_flag(task, TIF_IA32))
- task_pt_regs(task)->ss = value;
-#endif
+ task_pt_regs(task)->ss = value;
break;
}
diff --git a/arch/x86/kernel/syscall_32.c b/arch/x86/kernel/syscall_32.c
index e9bcd57d8a9e..3777189c4a19 100644
--- a/arch/x86/kernel/syscall_32.c
+++ b/arch/x86/kernel/syscall_32.c
@@ -5,21 +5,29 @@
#include <linux/cache.h>
#include <asm/asm-offsets.h>
-#define __SYSCALL_I386(nr, sym, compat) extern asmlinkage void sym(void) ;
+#ifdef CONFIG_IA32_EMULATION
+#define SYM(sym, compat) compat
+#else
+#define SYM(sym, compat) sym
+#define ia32_sys_call_table sys_call_table
+#define __NR_ia32_syscall_max __NR_syscall_max
+#endif
+
+#define __SYSCALL_I386(nr, sym, compat) extern asmlinkage void SYM(sym, compat)(void) ;
#include <asm/syscalls_32.h>
#undef __SYSCALL_I386
-#define __SYSCALL_I386(nr, sym, compat) [nr] = sym,
+#define __SYSCALL_I386(nr, sym, compat) [nr] = SYM(sym, compat),
typedef asmlinkage void (*sys_call_ptr_t)(void);
extern asmlinkage void sys_ni_syscall(void);
-__visible const sys_call_ptr_t sys_call_table[__NR_syscall_max+1] = {
+__visible const sys_call_ptr_t ia32_sys_call_table[__NR_ia32_syscall_max+1] = {
/*
* Smells like a compiler bug -- it doesn't work
* when the & below is removed.
*/
- [0 ... __NR_syscall_max] = &sys_ni_syscall,
+ [0 ... __NR_ia32_syscall_max] = &sys_ni_syscall,
#include <asm/syscalls_32.h>
};
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 9d2073e2ecc9..42819886be0c 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -925,9 +925,17 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
/* Set of traps needed for early debugging. */
void __init early_trap_init(void)
{
- set_intr_gate_ist(X86_TRAP_DB, &debug, DEBUG_STACK);
+ /*
+ * Don't set ist to DEBUG_STACK as it doesn't work until TSS is
+ * ready in cpu_init() <-- trap_init(). Before trap_init(), CPU
+ * runs at ring 0 so it is impossible to hit an invalid stack.
+ * Using the original stack works well enough at this early
+ * stage. DEBUG_STACK will be equipped after cpu_init() in
+ * trap_init().
+ */
+ set_intr_gate_ist(X86_TRAP_DB, &debug, 0);
/* int3 can be called from all */
- set_system_intr_gate_ist(X86_TRAP_BP, &int3, DEBUG_STACK);
+ set_system_intr_gate_ist(X86_TRAP_BP, &int3, 0);
#ifdef CONFIG_X86_32
set_intr_gate(X86_TRAP_PF, page_fault);
#endif
@@ -1005,6 +1013,15 @@ void __init trap_init(void)
*/
cpu_init();
+ /*
+ * X86_TRAP_DB and X86_TRAP_BP have been set
+ * in early_trap_init(). However, DEBUG_STACK works only after
+ * cpu_init() loads TSS. See comments in early_trap_init().
+ */
+ set_intr_gate_ist(X86_TRAP_DB, &debug, DEBUG_STACK);
+ /* int3 can be called from all */
+ set_system_intr_gate_ist(X86_TRAP_BP, &int3, DEBUG_STACK);
+
x86_init.irqs.trap_init();
#ifdef CONFIG_X86_64