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Diffstat (limited to 'arch/x86/kernel/traps.c')
-rw-r--r--arch/x86/kernel/traps.c169
1 files changed, 68 insertions, 101 deletions
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index a1d288327ff0..33399176512a 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -14,7 +14,6 @@
#include <linux/spinlock.h>
#include <linux/kprobes.h>
#include <linux/uaccess.h>
-#include <linux/utsname.h>
#include <linux/kdebug.h>
#include <linux/kernel.h>
#include <linux/module.h>
@@ -45,6 +44,7 @@
#include <linux/edac.h>
#endif
+#include <asm/kmemcheck.h>
#include <asm/stacktrace.h>
#include <asm/processor.h>
#include <asm/debugreg.h>
@@ -53,18 +53,17 @@
#include <asm/traps.h>
#include <asm/desc.h>
#include <asm/i387.h>
+#include <asm/mce.h>
#include <asm/mach_traps.h>
#ifdef CONFIG_X86_64
+#include <asm/x86_init.h>
#include <asm/pgalloc.h>
#include <asm/proto.h>
#else
#include <asm/processor-flags.h>
#include <asm/setup.h>
-#include <asm/traps.h>
-
-#include "cpu/mcheck/mce.h"
asmlinkage int system_call(void);
@@ -73,11 +72,9 @@ char ignore_fpu_irq;
/*
* The IDT has to be page-aligned to simplify the Pentium
- * F0 0F bug workaround.. We have a special link segment
- * for this.
+ * F0 0F bug workaround.
*/
-gate_desc idt_table[256]
- __attribute__((__section__(".data.idt"))) = { { { { 0, 0 } } }, };
+gate_desc idt_table[NR_VECTORS] __page_aligned_data = { { { { 0, 0 } } }, };
#endif
DECLARE_BITMAP(used_vectors, NR_VECTORS);
@@ -346,6 +343,9 @@ io_check_error(unsigned char reason, struct pt_regs *regs)
printk(KERN_EMERG "NMI: IOCK error (debug interrupt?)\n");
show_registers(regs);
+ if (panic_on_io_nmi)
+ panic("NMI IOCK error: Not continuing");
+
/* Re-enable the IOCK line, wait for a few seconds */
reason = (reason & 0xf) | 8;
outb(reason, 0x61);
@@ -529,73 +529,56 @@ asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs)
dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)
{
struct task_struct *tsk = current;
- unsigned long condition;
+ unsigned long dr6;
int si_code;
- get_debugreg(condition, 6);
+ get_debugreg(dr6, 6);
+
+ /* Catch kmemcheck conditions first of all! */
+ if ((dr6 & DR_STEP) && kmemcheck_trap(regs))
+ return;
+ /* DR6 may or may not be cleared by the CPU */
+ set_debugreg(0, 6);
/*
* The processor cleared BTF, so don't mark that we need it set.
*/
clear_tsk_thread_flag(tsk, TIF_DEBUGCTLMSR);
tsk->thread.debugctlmsr = 0;
- if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code,
- SIGTRAP) == NOTIFY_STOP)
+ /* Store the virtualized DR6 value */
+ tsk->thread.debugreg6 = dr6;
+
+ if (notify_die(DIE_DEBUG, "debug", regs, PTR_ERR(&dr6), error_code,
+ SIGTRAP) == NOTIFY_STOP)
return;
/* It's safe to allow irq's after DR6 has been saved */
preempt_conditional_sti(regs);
- /* Mask out spurious debug traps due to lazy DR7 setting */
- if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) {
- if (!tsk->thread.debugreg7)
- goto clear_dr7;
+ if (regs->flags & X86_VM_MASK) {
+ handle_vm86_trap((struct kernel_vm86_regs *) regs,
+ error_code, 1);
+ return;
}
-#ifdef CONFIG_X86_32
- if (regs->flags & X86_VM_MASK)
- goto debug_vm86;
-#endif
-
- /* Save debug status register where ptrace can see it */
- tsk->thread.debugreg6 = condition;
-
/*
- * Single-stepping through TF: make sure we ignore any events in
- * kernel space (but re-enable TF when returning to user mode).
+ * Single-stepping through system calls: ignore any exceptions in
+ * kernel space, but re-enable TF when returning to user mode.
+ *
+ * We already checked v86 mode above, so we can check for kernel mode
+ * by just checking the CPL of CS.
*/
- if (condition & DR_STEP) {
- if (!user_mode(regs))
- goto clear_TF_reenable;
+ if ((dr6 & DR_STEP) && !user_mode(regs)) {
+ tsk->thread.debugreg6 &= ~DR_STEP;
+ set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
+ regs->flags &= ~X86_EFLAGS_TF;
}
-
- si_code = get_si_code(condition);
- /* Ok, finally something we can handle */
- send_sigtrap(tsk, regs, error_code, si_code);
-
- /*
- * Disable additional traps. They'll be re-enabled when
- * the signal is delivered.
- */
-clear_dr7:
- set_debugreg(0, 7);
+ si_code = get_si_code(tsk->thread.debugreg6);
+ if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS))
+ send_sigtrap(tsk, regs, error_code, si_code);
preempt_conditional_cli(regs);
- return;
-
-#ifdef CONFIG_X86_32
-debug_vm86:
- /* reenable preemption: handle_vm86_trap() might sleep */
- dec_preempt_count();
- handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, 1);
- conditional_cli(regs);
- return;
-#endif
-clear_TF_reenable:
- set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
- regs->flags &= ~X86_EFLAGS_TF;
- preempt_conditional_cli(regs);
return;
}
@@ -779,34 +762,35 @@ do_spurious_interrupt_bug(struct pt_regs *regs, long error_code)
#endif
}
-#ifdef CONFIG_X86_32
-unsigned long patch_espfix_desc(unsigned long uesp, unsigned long kesp)
+asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void)
{
- struct desc_struct *gdt = get_cpu_gdt_table(smp_processor_id());
- unsigned long base = (kesp - uesp) & -THREAD_SIZE;
- unsigned long new_kesp = kesp - base;
- unsigned long lim_pages = (new_kesp | (THREAD_SIZE - 1)) >> PAGE_SHIFT;
- __u64 desc = *(__u64 *)&gdt[GDT_ENTRY_ESPFIX_SS];
-
- /* Set up base for espfix segment */
- desc &= 0x00f0ff0000000000ULL;
- desc |= ((((__u64)base) << 16) & 0x000000ffffff0000ULL) |
- ((((__u64)base) << 32) & 0xff00000000000000ULL) |
- ((((__u64)lim_pages) << 32) & 0x000f000000000000ULL) |
- (lim_pages & 0xffff);
- *(__u64 *)&gdt[GDT_ENTRY_ESPFIX_SS] = desc;
-
- return new_kesp;
}
-#else
-asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void)
+
+asmlinkage void __attribute__((weak)) smp_threshold_interrupt(void)
{
}
-asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
+/*
+ * __math_state_restore assumes that cr0.TS is already clear and the
+ * fpu state is all ready for use. Used during context switch.
+ */
+void __math_state_restore(void)
{
+ struct thread_info *thread = current_thread_info();
+ struct task_struct *tsk = thread->task;
+
+ /*
+ * Paranoid restore. send a SIGSEGV if we fail to restore the state.
+ */
+ if (unlikely(restore_fpu_checking(tsk))) {
+ stts();
+ force_sig(SIGSEGV, tsk);
+ return;
+ }
+
+ thread->status |= TS_USEDFPU; /* So we fnsave on switch_to() */
+ tsk->fpu_counter++;
}
-#endif
/*
* 'math_state_restore()' saves the current math information in the
@@ -839,20 +823,8 @@ asmlinkage void math_state_restore(void)
}
clts(); /* Allow maths ops (or we recurse) */
-#ifdef CONFIG_X86_32
- restore_fpu(tsk);
-#else
- /*
- * Paranoid restore. send a SIGSEGV if we fail to restore the state.
- */
- if (unlikely(restore_fpu_checking(tsk))) {
- stts();
- force_sig(SIGSEGV, tsk);
- return;
- }
-#endif
- thread->status |= TS_USEDFPU; /* So we fnsave on switch_to() */
- tsk->fpu_counter++;
+
+ __math_state_restore();
}
EXPORT_SYMBOL_GPL(math_state_restore);
@@ -945,8 +917,13 @@ void __init trap_init(void)
#endif
set_intr_gate(19, &simd_coprocessor_error);
+ /* Reserve all the builtin and the syscall vector: */
+ for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
+ set_bit(i, used_vectors);
+
#ifdef CONFIG_IA32_EMULATION
set_system_intr_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
+ set_bit(IA32_SYSCALL_VECTOR, used_vectors);
#endif
#ifdef CONFIG_X86_32
@@ -963,23 +940,13 @@ void __init trap_init(void)
}
set_system_trap_gate(SYSCALL_VECTOR, &system_call);
-#endif
-
- /* Reserve all the builtin and the syscall vector: */
- for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
- set_bit(i, used_vectors);
-
-#ifdef CONFIG_X86_64
- set_bit(IA32_SYSCALL_VECTOR, used_vectors);
-#else
set_bit(SYSCALL_VECTOR, used_vectors);
#endif
+
/*
* Should be a barrier for any external CPU state:
*/
cpu_init();
-#ifdef CONFIG_X86_32
- x86_quirk_trap_init();
-#endif
+ x86_init.irqs.trap_init();
}