[PATCH 8/9] traps: x86: make traps_32.c and traps_64.c equal

From: Alexander van Heukelum
Date: Fri Oct 03 2008 - 16:37:42 EST

Use CONFIG_X86_64/CONFIG_X86_32 to condtionally compile the
parts needed for x86_64 or i386 only.

Runs a small userspace for a number of minimal configurations
and boots the defconfigs.

Signed-off-by: Alexander van Heukelum <heukelum@xxxxxxxxxxx>
---
arch/x86/kernel/traps_32.c | 172 ++++++++++++++++++++-
arch/x86/kernel/traps_64.c | 367 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 536 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c
index d994e92..54e08d2 100644
--- a/arch/x86/kernel/traps_32.c
+++ b/arch/x86/kernel/traps_32.c
@@ -59,6 +59,11 @@

#include <mach_traps.h>

+#ifdef CONFIG_X86_64
+#include <asm/pgalloc.h>
+#include <asm/proto.h>
+#include <asm/pda.h>
+#else
#include <asm/processor-flags.h>
#include <asm/arch_hooks.h>
#include <asm/nmi.h>
@@ -82,6 +87,7 @@ char ignore_fpu_irq;
*/
gate_desc idt_table[256]
__attribute__((__section__(".data.idt"))) = { { { { 0, 0 } } }, };
+#endif

static int ignore_nmis;

@@ -105,6 +111,7 @@ static inline void preempt_conditional_cli(struct pt_regs *regs)
dec_preempt_count();
}

+#ifdef CONFIG_X86_32
static inline void
die_if_kernel(const char *str, struct pt_regs *regs, long err)
{
@@ -152,6 +159,7 @@ static int lazy_iobitmap_copy(void)

return 0;
}
+#endif

static void __kprobes
do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
@@ -159,6 +167,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
{
struct task_struct *tsk = current;

+#ifdef CONFIG_X86_32
if (regs->flags & X86_VM_MASK) {
/*
* traps 0, 1, 3, 4, and 5 should be forwarded to vm86.
@@ -168,11 +177,14 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
goto vm86_trap;
goto trap_signal;
}
+#endif

if (!user_mode(regs))
goto kernel_trap;

+#ifdef CONFIG_X86_32
trap_signal:
+#endif
/*
* We want error_code and trap_no set for userspace faults and
* kernelspace faults which result in die(), but not
@@ -185,6 +197,18 @@ trap_signal:
tsk->thread.error_code = error_code;
tsk->thread.trap_no = trapnr;

+#ifdef CONFIG_X86_64
+ if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
+ printk_ratelimit()) {
+ printk(KERN_INFO
+ "%s[%d] trap %s ip:%lx sp:%lx error:%lx",
+ tsk->comm, tsk->pid, str,
+ regs->ip, regs->sp, error_code);
+ print_vma_addr(" in ", regs->ip);
+ printk("\n");
+ }
+#endif
+
if (info)
force_sig_info(signr, info, tsk);
else
@@ -199,11 +223,13 @@ kernel_trap:
}
return;

+#ifdef CONFIG_X86_32
vm86_trap:
if (handle_vm86_trap((struct kernel_vm86_regs *) regs,
error_code, trapnr))
goto trap_signal;
return;
+#endif
}

#define DO_ERROR(trapnr, signr, str, name) \
@@ -238,9 +264,41 @@ DO_ERROR_INFO(6, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, regs->ip)
DO_ERROR(9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun)
DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
DO_ERROR(11, SIGBUS, "segment not present", segment_not_present)
+#ifdef CONFIG_X86_32
DO_ERROR(12, SIGBUS, "stack segment", stack_segment)
+#endif
DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)

+#ifdef CONFIG_X86_64
+/* Runs on IST stack */
+dotraplinkage void do_stack_segment(struct pt_regs *regs, long error_code)
+{
+ if (notify_die(DIE_TRAP, "stack segment", regs, error_code,
+ 12, SIGBUS) == NOTIFY_STOP)
+ return;
+ preempt_conditional_sti(regs);
+ do_trap(12, SIGBUS, "stack segment", regs, error_code, NULL);
+ preempt_conditional_cli(regs);
+}
+
+dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
+{
+ static const char str[] = "double fault";
+ struct task_struct *tsk = current;
+
+ /* Return not checked because double check cannot be ignored */
+ notify_die(DIE_TRAP, str, regs, error_code, 8, SIGSEGV);
+
+ tsk->thread.error_code = error_code;
+ tsk->thread.trap_no = 8;
+
+ /* This is always a kernel trap and never fixable (and thus must
+ never return). */
+ for (;;)
+ die(str, regs, error_code);
+}
+#endif
+
dotraplinkage void __kprobes
do_general_protection(struct pt_regs *regs, long error_code)
{
@@ -248,6 +306,7 @@ do_general_protection(struct pt_regs *regs, long error_code)

conditional_sti(regs);

+#ifdef CONFIG_X86_32
if (lazy_iobitmap_copy()) {
/* restart the faulting instruction */
return;
@@ -255,6 +314,7 @@ do_general_protection(struct pt_regs *regs, long error_code)

if (regs->flags & X86_VM_MASK)
goto gp_in_vm86;
+#endif

tsk = current;
if (!user_mode(regs))
@@ -276,10 +336,12 @@ do_general_protection(struct pt_regs *regs, long error_code)
force_sig(SIGSEGV, tsk);
return;

+#ifdef CONFIG_X86_32
gp_in_vm86:
local_irq_enable();
handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code);
return;
+#endif

gp_in_kernel:
if (fixup_exception(regs))
@@ -367,6 +429,7 @@ unknown_nmi_error(unsigned char reason, struct pt_regs *regs)
printk(KERN_EMERG "Dazed and confused, but trying to continue\n");
}

+#ifdef CONFIG_X86_32
static DEFINE_SPINLOCK(nmi_print_lock);

void notrace __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic)
@@ -401,6 +464,7 @@ void notrace __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic)

do_exit(SIGSEGV);
}
+#endif

static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
{
@@ -440,11 +504,13 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
mem_parity_error(reason, regs);
if (reason & 0x40)
io_check_error(reason, regs);
+#ifdef CONFIG_X86_32
/*
* Reassert NMI in case it became active meanwhile
* as it's edge-triggered:
*/
reassert_nmi();
+#endif
}

dotraplinkage notrace __kprobes void
@@ -452,7 +518,11 @@ do_nmi(struct pt_regs *regs, long error_code)
{
nmi_enter();

+#ifdef CONFIG_X86_32
{ int cpu; cpu = smp_processor_id(); ++nmi_count(cpu); }
+#else
+ add_pda(__nmi_count, 1);
+#endif

if (!ignore_nmis)
default_do_nmi(regs);
@@ -490,6 +560,29 @@ dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code)
preempt_conditional_cli(regs);
}

+#ifdef CONFIG_X86_64
+/* Help handler running on IST stack to switch back to user stack
+ for scheduling or signal handling. The actual stack switch is done in
+ entry.S */
+asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs)
+{
+ struct pt_regs *regs = eregs;
+ /* Did already sync */
+ if (eregs == (struct pt_regs *)eregs->sp)
+ ;
+ /* Exception from user space */
+ else if (user_mode(eregs))
+ regs = task_pt_regs(current);
+ /* Exception from kernel and interrupts are enabled. Move to
+ kernel process stack. */
+ else if (eregs->flags & X86_EFLAGS_IF)
+ regs = (struct pt_regs *)(eregs->sp -= sizeof(struct pt_regs));
+ if (eregs != regs)
+ *regs = *eregs;
+ return regs;
+}
+#endif
+
/*
* Our handling of the processor debug registers is non-trivial.
* We do not clear them on entry and exit from the kernel. Therefore
@@ -545,8 +638,10 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)
goto clear_dr7;
}

+#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;
@@ -573,10 +668,12 @@ clear_dr7:
preempt_conditional_cli(regs);
return;

+#ifdef CONFIG_X86_32
debug_vm86:
handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, 1);
preempt_conditional_cli(regs);
return;
+#endif

clear_TF_reenable:
set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
@@ -585,6 +682,20 @@ clear_TF_reenable:
return;
}

+#ifdef CONFIG_X86_64
+static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
+{
+ if (fixup_exception(regs))
+ return 1;
+
+ notify_die(DIE_GPF, str, regs, 0, trapnr, SIGFPE);
+ /* Illegal floating point operation in the kernel */
+ current->thread.trap_no = trapnr;
+ die(str, regs, 0);
+ return 0;
+}
+#endif
+
/*
* Note that we play around with the 'TS' bit in an attempt to get
* the correct behaviour even in the presence of the asynchronous
@@ -621,7 +732,9 @@ void math_error(void __user *ip)
swd = get_fpu_swd(task);
switch (swd & ~cwd & 0x3f) {
case 0x000: /* No unmasked exception */
+#ifdef CONFIG_X86_32
return;
+#endif
default: /* Multiple exceptions */
break;
case 0x001: /* Invalid Op */
@@ -652,7 +765,15 @@ void math_error(void __user *ip)
dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
{
conditional_sti(regs);
+
+#ifdef CONFIG_X86_32
ignore_fpu_irq = 1;
+#else
+ if (!user_mode(regs) &&
+ kernel_math_error(regs, "kernel x87 math error", 16))
+ return;
+#endif
+
math_error((void __user *)regs->ip);
}

@@ -709,6 +830,7 @@ do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
{
conditional_sti(regs);

+#ifdef CONFIG_X86_32
if (cpu_has_xmm) {
/* Handle SIMD FPU exceptions on PIII+ processors. */
ignore_fpu_irq = 1;
@@ -727,6 +849,12 @@ do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
current->thread.error_code = error_code;
die_if_kernel("cache flush denied", regs, error_code);
force_sig(SIGSEGV, current);
+#else
+ if (!user_mode(regs) &&
+ kernel_math_error(regs, "kernel simd math error", 19))
+ return;
+ simd_math_error((void __user *)regs->ip);
+#endif
}

dotraplinkage void
@@ -739,6 +867,7 @@ 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)
{
struct desc_struct *gdt = get_cpu_gdt_table(smp_processor_id());
@@ -757,6 +886,15 @@ unsigned long patch_espfix_desc(unsigned long uesp, unsigned long kesp)

return new_kesp;
}
+#else
+asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void)
+{
+}
+
+asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
+{
+}
+#endif

/*
* 'math_state_restore()' saves the current math information in the
@@ -789,14 +927,24 @@ 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++;
}
EXPORT_SYMBOL_GPL(math_state_restore);

#ifndef CONFIG_MATH_EMULATION
-
asmlinkage void math_emulate(long arg)
{
printk(KERN_EMERG
@@ -805,12 +953,12 @@ asmlinkage void math_emulate(long arg)
force_sig(SIGFPE, current);
schedule();
}
-
#endif /* CONFIG_MATH_EMULATION */

dotraplinkage void __kprobes
do_device_not_available(struct pt_regs *regs, long error)
{
+#ifdef CONFIG_X86_32
if (read_cr0() & X86_CR0_EM) {
conditional_sti(regs);
math_emulate(0);
@@ -818,8 +966,12 @@ do_device_not_available(struct pt_regs *regs, long error)
math_state_restore(); /* interrupts still off */
conditional_sti(regs);
}
+#else
+ math_state_restore();
+#endif
}

+#ifdef CONFIG_X86_32
#ifdef CONFIG_X86_MCE
dotraplinkage void __kprobes do_machine_check(struct pt_regs *regs, long error)
{
@@ -842,10 +994,13 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
return;
do_trap(32, SIGILL, "iret exception", regs, error_code, &info);
}
+#endif

void __init trap_init(void)
{
+#ifdef CONFIG_X86_32
int i;
+#endif

#ifdef CONFIG_EISA
void __iomem *p = early_ioremap(0x0FFFD9, 4);
@@ -865,7 +1020,11 @@ void __init trap_init(void)
set_intr_gate(5, &bounds);
set_intr_gate(6, &invalid_op);
set_intr_gate(7, &device_not_available);
+#ifdef CONFIG_X86_32
set_task_gate(8, GDT_ENTRY_DOUBLEFAULT_TSS);
+#else
+ set_intr_gate_ist(8, &double_fault, DOUBLEFAULT_STACK);
+#endif
set_intr_gate(9, &coprocessor_segment_overrun);
set_intr_gate(10, &invalid_TSS);
set_intr_gate(11, &segment_not_present);
@@ -880,6 +1039,11 @@ void __init trap_init(void)
#endif
set_intr_gate(19, &simd_coprocessor_error);

+#ifdef CONFIG_IA32_EMULATION
+ set_system_intr_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
+#endif
+
+#ifdef CONFIG_X86_32
if (cpu_has_fxsr) {
printk(KERN_INFO "Enabling fast FPU save and restore... ");
set_in_cr4(X86_CR4_OSFXSR);
@@ -899,11 +1063,13 @@ void __init trap_init(void)
set_bit(i, used_vectors);

set_bit(SYSCALL_VECTOR, used_vectors);
-
+#endif
/*
* Should be a barrier for any external CPU state:
*/
cpu_init();

+#ifdef CONFIG_X86_32
trap_init_hook();
+#endif
}
diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
index 334a3df..54e08d2 100644
--- a/arch/x86/kernel/traps_64.c
+++ b/arch/x86/kernel/traps_64.c
@@ -33,6 +33,15 @@
#include <linux/smp.h>
#include <linux/io.h>

+#ifdef CONFIG_EISA
+#include <linux/ioport.h>
+#include <linux/eisa.h>
+#endif
+
+#ifdef CONFIG_MCA
+#include <linux/mca.h>
+#endif
+
#if defined(CONFIG_EDAC)
#include <linux/edac.h>
#endif
@@ -50,10 +59,35 @@

#include <mach_traps.h>

+#ifdef CONFIG_X86_64
#include <asm/pgalloc.h>
#include <asm/proto.h>
#include <asm/pda.h>
+#else
+#include <asm/processor-flags.h>
+#include <asm/arch_hooks.h>
+#include <asm/nmi.h>
+#include <asm/smp.h>
+#include <asm/io.h>
+
+#include "cpu/mcheck/mce.h"

+DECLARE_BITMAP(used_vectors, NR_VECTORS);
+EXPORT_SYMBOL_GPL(used_vectors);
+
+asmlinkage int system_call(void);
+
+/* Do we ignore FPU interrupts ? */
+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.
+ */
+gate_desc idt_table[256]
+ __attribute__((__section__(".data.idt"))) = { { { { 0, 0 } } }, };
+#endif

static int ignore_nmis;

@@ -77,15 +111,80 @@ static inline void preempt_conditional_cli(struct pt_regs *regs)
dec_preempt_count();
}

+#ifdef CONFIG_X86_32
+static inline void
+die_if_kernel(const char *str, struct pt_regs *regs, long err)
+{
+ if (!user_mode_vm(regs))
+ die(str, regs, err);
+}
+
+/*
+ * Perform the lazy TSS's I/O bitmap copy. If the TSS has an
+ * invalid offset set (the LAZY one) and the faulting thread has
+ * a valid I/O bitmap pointer, we copy the I/O bitmap in the TSS,
+ * we set the offset field correctly and return 1.
+ */
+static int lazy_iobitmap_copy(void)
+{
+ struct thread_struct *thread;
+ struct tss_struct *tss;
+ int cpu;
+
+ cpu = get_cpu();
+ tss = &per_cpu(init_tss, cpu);
+ thread = &current->thread;
+
+ if (tss->x86_tss.io_bitmap_base == INVALID_IO_BITMAP_OFFSET_LAZY &&
+ thread->io_bitmap_ptr) {
+ memcpy(tss->io_bitmap, thread->io_bitmap_ptr,
+ thread->io_bitmap_max);
+ /*
+ * If the previously set map was extending to higher ports
+ * than the current one, pad extra space with 0xff (no access).
+ */
+ if (thread->io_bitmap_max < tss->io_bitmap_max) {
+ memset((char *) tss->io_bitmap +
+ thread->io_bitmap_max, 0xff,
+ tss->io_bitmap_max - thread->io_bitmap_max);
+ }
+ tss->io_bitmap_max = thread->io_bitmap_max;
+ tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;
+ tss->io_bitmap_owner = thread;
+ put_cpu();
+
+ return 1;
+ }
+ put_cpu();
+
+ return 0;
+}
+#endif
+
static void __kprobes
do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
long error_code, siginfo_t *info)
{
struct task_struct *tsk = current;

+#ifdef CONFIG_X86_32
+ if (regs->flags & X86_VM_MASK) {
+ /*
+ * traps 0, 1, 3, 4, and 5 should be forwarded to vm86.
+ * On nmi (interrupt 2), do_trap should not be called.
+ */
+ if (trapnr < 6)
+ goto vm86_trap;
+ goto trap_signal;
+ }
+#endif
+
if (!user_mode(regs))
goto kernel_trap;

+#ifdef CONFIG_X86_32
+trap_signal:
+#endif
/*
* We want error_code and trap_no set for userspace faults and
* kernelspace faults which result in die(), but not
@@ -98,6 +197,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
tsk->thread.error_code = error_code;
tsk->thread.trap_no = trapnr;

+#ifdef CONFIG_X86_64
if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
printk_ratelimit()) {
printk(KERN_INFO
@@ -107,6 +207,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
print_vma_addr(" in ", regs->ip);
printk("\n");
}
+#endif

if (info)
force_sig_info(signr, info, tsk);
@@ -121,6 +222,14 @@ kernel_trap:
die(str, regs, error_code);
}
return;
+
+#ifdef CONFIG_X86_32
+vm86_trap:
+ if (handle_vm86_trap((struct kernel_vm86_regs *) regs,
+ error_code, trapnr))
+ goto trap_signal;
+ return;
+#endif
}

#define DO_ERROR(trapnr, signr, str, name) \
@@ -155,8 +264,12 @@ DO_ERROR_INFO(6, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, regs->ip)
DO_ERROR(9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun)
DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
DO_ERROR(11, SIGBUS, "segment not present", segment_not_present)
+#ifdef CONFIG_X86_32
+DO_ERROR(12, SIGBUS, "stack segment", stack_segment)
+#endif
DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)

+#ifdef CONFIG_X86_64
/* Runs on IST stack */
dotraplinkage void do_stack_segment(struct pt_regs *regs, long error_code)
{
@@ -184,6 +297,7 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
for (;;)
die(str, regs, error_code);
}
+#endif

dotraplinkage void __kprobes
do_general_protection(struct pt_regs *regs, long error_code)
@@ -192,6 +306,16 @@ do_general_protection(struct pt_regs *regs, long error_code)

conditional_sti(regs);

+#ifdef CONFIG_X86_32
+ if (lazy_iobitmap_copy()) {
+ /* restart the faulting instruction */
+ return;
+ }
+
+ if (regs->flags & X86_VM_MASK)
+ goto gp_in_vm86;
+#endif
+
tsk = current;
if (!user_mode(regs))
goto gp_in_kernel;
@@ -212,6 +336,13 @@ do_general_protection(struct pt_regs *regs, long error_code)
force_sig(SIGSEGV, tsk);
return;

+#ifdef CONFIG_X86_32
+gp_in_vm86:
+ local_irq_enable();
+ handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code);
+ return;
+#endif
+
gp_in_kernel:
if (fixup_exception(regs))
return;
@@ -277,6 +408,16 @@ unknown_nmi_error(unsigned char reason, struct pt_regs *regs)
if (notify_die(DIE_NMIUNKNOWN, "nmi", regs, reason, 2, SIGINT) ==
NOTIFY_STOP)
return;
+#ifdef CONFIG_MCA
+ /*
+ * Might actually be able to figure out what the guilty party
+ * is:
+ */
+ if (MCA_bus) {
+ mca_handle_nmi();
+ return;
+ }
+#endif
printk(KERN_EMERG
"Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
reason, smp_processor_id());
@@ -288,6 +429,43 @@ unknown_nmi_error(unsigned char reason, struct pt_regs *regs)
printk(KERN_EMERG "Dazed and confused, but trying to continue\n");
}

+#ifdef CONFIG_X86_32
+static DEFINE_SPINLOCK(nmi_print_lock);
+
+void notrace __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic)
+{
+ if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
+ return;
+
+ spin_lock(&nmi_print_lock);
+ /*
+ * We are in trouble anyway, lets at least try
+ * to get a message out:
+ */
+ bust_spinlocks(1);
+ printk(KERN_EMERG "%s", str);
+ printk(" on CPU%d, ip %08lx, registers:\n",
+ smp_processor_id(), regs->ip);
+ show_registers(regs);
+ if (do_panic)
+ panic("Non maskable interrupt");
+ console_silent();
+ spin_unlock(&nmi_print_lock);
+ bust_spinlocks(0);
+
+ /*
+ * If we are in kernel we are probably nested up pretty bad
+ * and might aswell get out now while we still can:
+ */
+ if (!user_mode_vm(regs)) {
+ current->thread.trap_no = 2;
+ crash_kexec(regs);
+ }
+
+ do_exit(SIGSEGV);
+}
+#endif
+
static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
{
unsigned char reason = 0;
@@ -303,6 +481,7 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT)
== NOTIFY_STOP)
return;
+#ifdef CONFIG_X86_LOCAL_APIC
/*
* Ok, so this is none of the documented NMI sources,
* so it must be the NMI watchdog.
@@ -311,6 +490,9 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
return;
if (!do_nmi_callback(regs, cpu))
unknown_nmi_error(reason, regs);
+#else
+ unknown_nmi_error(reason, regs);
+#endif

return;
}
@@ -322,6 +504,13 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
mem_parity_error(reason, regs);
if (reason & 0x40)
io_check_error(reason, regs);
+#ifdef CONFIG_X86_32
+ /*
+ * Reassert NMI in case it became active meanwhile
+ * as it's edge-triggered:
+ */
+ reassert_nmi();
+#endif
}

dotraplinkage notrace __kprobes void
@@ -329,7 +518,11 @@ do_nmi(struct pt_regs *regs, long error_code)
{
nmi_enter();

+#ifdef CONFIG_X86_32
+ { int cpu; cpu = smp_processor_id(); ++nmi_count(cpu); }
+#else
add_pda(__nmi_count, 1);
+#endif

if (!ignore_nmis)
default_do_nmi(regs);
@@ -352,15 +545,22 @@ void restart_nmi(void)
/* May run on IST stack. */
dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code)
{
+#ifdef CONFIG_KPROBES
if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
== NOTIFY_STOP)
return;
+#else
+ if (notify_die(DIE_TRAP, "int3", regs, error_code, 3, SIGTRAP)
+ == NOTIFY_STOP)
+ return;
+#endif

preempt_conditional_sti(regs);
do_trap(3, SIGTRAP, "int3", regs, error_code, NULL);
preempt_conditional_cli(regs);
}

+#ifdef CONFIG_X86_64
/* Help handler running on IST stack to switch back to user stack
for scheduling or signal handling. The actual stack switch is done in
entry.S */
@@ -381,6 +581,7 @@ asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs)
*regs = *eregs;
return regs;
}
+#endif

/*
* Our handling of the processor debug registers is non-trivial.
@@ -437,6 +638,11 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)
goto clear_dr7;
}

+#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;

@@ -462,6 +668,13 @@ clear_dr7:
preempt_conditional_cli(regs);
return;

+#ifdef CONFIG_X86_32
+debug_vm86:
+ handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, 1);
+ preempt_conditional_cli(regs);
+ return;
+#endif
+
clear_TF_reenable:
set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
regs->flags &= ~X86_EFLAGS_TF;
@@ -469,6 +682,7 @@ clear_TF_reenable:
return;
}

+#ifdef CONFIG_X86_64
static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
{
if (fixup_exception(regs))
@@ -480,6 +694,7 @@ static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
die(str, regs, 0);
return 0;
}
+#endif

/*
* Note that we play around with the 'TS' bit in an attempt to get
@@ -517,6 +732,9 @@ void math_error(void __user *ip)
swd = get_fpu_swd(task);
switch (swd & ~cwd & 0x3f) {
case 0x000: /* No unmasked exception */
+#ifdef CONFIG_X86_32
+ return;
+#endif
default: /* Multiple exceptions */
break;
case 0x001: /* Invalid Op */
@@ -547,9 +765,15 @@ void math_error(void __user *ip)
dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
{
conditional_sti(regs);
+
+#ifdef CONFIG_X86_32
+ ignore_fpu_irq = 1;
+#else
if (!user_mode(regs) &&
kernel_math_error(regs, "kernel x87 math error", 16))
return;
+#endif
+
math_error((void __user *)regs->ip);
}

@@ -605,17 +829,64 @@ dotraplinkage void
do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
{
conditional_sti(regs);
+
+#ifdef CONFIG_X86_32
+ if (cpu_has_xmm) {
+ /* Handle SIMD FPU exceptions on PIII+ processors. */
+ ignore_fpu_irq = 1;
+ simd_math_error((void __user *)regs->ip);
+ return;
+ }
+ /*
+ * Handle strange cache flush from user space exception
+ * in all other cases. This is undocumented behaviour.
+ */
+ if (regs->flags & X86_VM_MASK) {
+ handle_vm86_fault((struct kernel_vm86_regs *)regs, error_code);
+ return;
+ }
+ current->thread.trap_no = 19;
+ current->thread.error_code = error_code;
+ die_if_kernel("cache flush denied", regs, error_code);
+ force_sig(SIGSEGV, current);
+#else
if (!user_mode(regs) &&
kernel_math_error(regs, "kernel simd math error", 19))
return;
simd_math_error((void __user *)regs->ip);
+#endif
}

dotraplinkage void
do_spurious_interrupt_bug(struct pt_regs *regs, long error_code)
{
+ conditional_sti(regs);
+#if 0
+ /* No need to warn about this any longer. */
+ printk(KERN_INFO "Ignoring P6 Local APIC Spurious Interrupt Bug...\n");
+#endif
}

+#ifdef CONFIG_X86_32
+unsigned long patch_espfix_desc(unsigned long uesp, unsigned long kesp)
+{
+ 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)
{
}
@@ -623,6 +894,7 @@ asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void)
asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
{
}
+#endif

/*
* 'math_state_restore()' saves the current math information in the
@@ -630,6 +902,9 @@ asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
*
* Careful.. There are problems with IBM-designed IRQ13 behaviour.
* Don't touch unless you *really* know how it works.
+ *
+ * Must be called with kernel preemption disabled (in this case,
+ * local interrupts are disabled at the call-site in entry.S).
*/
asmlinkage void math_state_restore(void)
{
@@ -652,6 +927,9 @@ 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.
*/
@@ -660,19 +938,78 @@ asmlinkage void math_state_restore(void)
force_sig(SIGSEGV, tsk);
return;
}
+#endif
thread->status |= TS_USEDFPU; /* So we fnsave on switch_to() */
tsk->fpu_counter++;
}
EXPORT_SYMBOL_GPL(math_state_restore);

+#ifndef CONFIG_MATH_EMULATION
+asmlinkage void math_emulate(long arg)
+{
+ printk(KERN_EMERG
+ "math-emulation not enabled and no coprocessor found.\n");
+ printk(KERN_EMERG "killing %s.\n", current->comm);
+ force_sig(SIGFPE, current);
+ schedule();
+}
+#endif /* CONFIG_MATH_EMULATION */
+
dotraplinkage void __kprobes
do_device_not_available(struct pt_regs *regs, long error)
{
+#ifdef CONFIG_X86_32
+ if (read_cr0() & X86_CR0_EM) {
+ conditional_sti(regs);
+ math_emulate(0);
+ } else {
+ math_state_restore(); /* interrupts still off */
+ conditional_sti(regs);
+ }
+#else
math_state_restore();
+#endif
+}
+
+#ifdef CONFIG_X86_32
+#ifdef CONFIG_X86_MCE
+dotraplinkage void __kprobes do_machine_check(struct pt_regs *regs, long error)
+{
+ conditional_sti(regs);
+ machine_check_vector(regs, error);
}
+#endif
+
+dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
+{
+ siginfo_t info;
+ local_irq_enable();
+
+ info.si_signo = SIGILL;
+ info.si_errno = 0;
+ info.si_code = ILL_BADSTK;
+ info.si_addr = 0;
+ if (notify_die(DIE_TRAP, "iret exception",
+ regs, error_code, 32, SIGILL) == NOTIFY_STOP)
+ return;
+ do_trap(32, SIGILL, "iret exception", regs, error_code, &info);
+}
+#endif

void __init trap_init(void)
{
+#ifdef CONFIG_X86_32
+ int i;
+#endif
+
+#ifdef CONFIG_EISA
+ void __iomem *p = early_ioremap(0x0FFFD9, 4);
+
+ if (readl(p) == 'E' + ('I'<<8) + ('S'<<16) + ('A'<<24))
+ EISA_bus = 1;
+ early_iounmap(p, 4);
+#endif
+
set_intr_gate(0, &divide_error);
set_intr_gate_ist(1, &debug, DEBUG_STACK);
set_intr_gate_ist(2, &nmi, NMI_STACK);
@@ -683,7 +1020,11 @@ void __init trap_init(void)
set_intr_gate(5, &bounds);
set_intr_gate(6, &invalid_op);
set_intr_gate(7, &device_not_available);
+#ifdef CONFIG_X86_32
+ set_task_gate(8, GDT_ENTRY_DOUBLEFAULT_TSS);
+#else
set_intr_gate_ist(8, &double_fault, DOUBLEFAULT_STACK);
+#endif
set_intr_gate(9, &coprocessor_segment_overrun);
set_intr_gate(10, &invalid_TSS);
set_intr_gate(11, &segment_not_present);
@@ -701,8 +1042,34 @@ void __init trap_init(void)
#ifdef CONFIG_IA32_EMULATION
set_system_intr_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
#endif
+
+#ifdef CONFIG_X86_32
+ if (cpu_has_fxsr) {
+ printk(KERN_INFO "Enabling fast FPU save and restore... ");
+ set_in_cr4(X86_CR4_OSFXSR);
+ printk("done.\n");
+ }
+ if (cpu_has_xmm) {
+ printk(KERN_INFO
+ "Enabling unmasked SIMD FPU exception support... ");
+ set_in_cr4(X86_CR4_OSXMMEXCPT);
+ printk("done.\n");
+ }
+
+ set_system_trap_gate(SYSCALL_VECTOR, &system_call);
+
+ /* Reserve all the builtin and the syscall vector: */
+ for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
+ set_bit(i, used_vectors);
+
+ set_bit(SYSCALL_VECTOR, used_vectors);
+#endif
/*
* Should be a barrier for any external CPU state:
*/
cpu_init();
+
+#ifdef CONFIG_X86_32
+ trap_init_hook();
+#endif
}
--
1.5.4.3

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