#include <asm/ftrace.h>
#include <asm/traps.h>
#include <asm/desc.h>
-#include <asm/i387.h>
-#include <asm/fpu-internal.h>
+#include <asm/fpu/internal.h>
#include <asm/mce.h>
#include <asm/fixmap.h>
#include <asm/mach_traps.h>
#include <asm/alternative.h>
+#include <asm/fpu/xstate.h>
+#include <asm/trace/mpx.h>
#include <asm/mpx.h>
+#include <asm/vm86.h>
#ifdef CONFIG_X86_64
#include <asm/x86_init.h>
#else
#include <asm/processor-flags.h>
#include <asm/setup.h>
-
-asmlinkage int system_call(void);
+#include <asm/proto.h>
#endif
/* Must be page-aligned because the real IDT is used in a fixmap. */
local_irq_enable();
}
-static inline void conditional_sti_ist(struct pt_regs *regs)
+static inline void preempt_conditional_sti(struct pt_regs *regs)
{
-#ifdef CONFIG_X86_64
- /*
- * X86_64 uses a per CPU stack on the IST for certain traps
- * like int3. The task can not be preempted when using one
- * of these stacks, thus preemption must be disabled, otherwise
- * the stack can be corrupted if the task is scheduled out,
- * and another task comes in and uses this stack.
- *
- * On x86_32 the task keeps its own stack and it is OK if the
- * task schedules out.
- */
preempt_count_inc();
-#endif
if (regs->flags & X86_EFLAGS_IF)
local_irq_enable();
}
local_irq_disable();
}
-static inline void conditional_cli_ist(struct pt_regs *regs)
+static inline void preempt_conditional_cli(struct pt_regs *regs)
{
if (regs->flags & X86_EFLAGS_IF)
local_irq_disable();
-#ifdef CONFIG_X86_64
preempt_count_dec();
-#endif
}
-enum ctx_state ist_enter(struct pt_regs *regs)
+void ist_enter(struct pt_regs *regs)
{
- enum ctx_state prev_state;
-
if (user_mode(regs)) {
- /* Other than that, we're just an exception. */
- prev_state = exception_enter();
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
} else {
/*
* We might have interrupted pretty much anything. In
* but we need to notify RCU.
*/
rcu_nmi_enter();
- prev_state = CONTEXT_KERNEL; /* the value is irrelevant. */
}
/*
- * We are atomic because we're on the IST stack (or we're on x86_32,
- * in which case we still shouldn't schedule).
- *
- * This must be after exception_enter(), because exception_enter()
- * won't do anything if in_interrupt() returns true.
+ * We are atomic because we're on the IST stack; or we're on
+ * x86_32, in which case we still shouldn't schedule; or we're
+ * on x86_64 and entered from user mode, in which case we're
+ * still atomic unless ist_begin_non_atomic is called.
*/
preempt_count_add(HARDIRQ_OFFSET);
/* This code is a bit fragile. Test it. */
- rcu_lockdep_assert(rcu_is_watching(), "ist_enter didn't work");
-
- return prev_state;
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "ist_enter didn't work");
}
-void ist_exit(struct pt_regs *regs, enum ctx_state prev_state)
+void ist_exit(struct pt_regs *regs)
{
- /* Must be before exception_exit. */
preempt_count_sub(HARDIRQ_OFFSET);
- if (user_mode(regs))
- return exception_exit(prev_state);
- else
+ if (!user_mode(regs))
rcu_nmi_exit();
}
* a double fault, it can be safe to schedule. ist_begin_non_atomic()
* begins a non-atomic section within an ist_enter()/ist_exit() region.
* Callers are responsible for enabling interrupts themselves inside
- * the non-atomic section, and callers must call is_end_non_atomic()
+ * the non-atomic section, and callers must call ist_end_non_atomic()
* before ist_exit().
*/
void ist_begin_non_atomic(struct pt_regs *regs)
static void do_error_trap(struct pt_regs *regs, long error_code, char *str,
unsigned long trapnr, int signr)
{
- enum ctx_state prev_state = exception_enter();
siginfo_t info;
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
+
if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) !=
NOTIFY_STOP) {
conditional_sti(regs);
do_trap(trapnr, signr, str, regs, error_code,
fill_trap_info(regs, signr, trapnr, &info));
}
-
- exception_exit(prev_state);
}
#define DO_ERROR(trapnr, signr, str, name) \
}
#endif
- ist_enter(regs); /* Discard prev_state because we won't return. */
+ ist_enter(regs);
notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV);
tsk->thread.error_code = error_code;
dotraplinkage void do_bounds(struct pt_regs *regs, long error_code)
{
- struct task_struct *tsk = current;
- struct xsave_struct *xsave_buf;
- enum ctx_state prev_state;
- struct bndcsr *bndcsr;
+ const struct mpx_bndcsr *bndcsr;
siginfo_t *info;
- prev_state = exception_enter();
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
if (notify_die(DIE_TRAP, "bounds", regs, error_code,
X86_TRAP_BR, SIGSEGV) == NOTIFY_STOP)
- goto exit;
+ return;
conditional_sti(regs);
if (!user_mode(regs))
/*
* We need to look at BNDSTATUS to resolve this exception.
- * It is not directly accessible, though, so we need to
- * do an xsave and then pull it out of the xsave buffer.
+ * A NULL here might mean that it is in its 'init state',
+ * which is all zeros which indicates MPX was not
+ * responsible for the exception.
*/
- fpu_save_init(&tsk->thread.fpu);
- xsave_buf = &(tsk->thread.fpu.state->xsave);
- bndcsr = get_xsave_addr(xsave_buf, XSTATE_BNDCSR);
+ bndcsr = get_xsave_field_ptr(XFEATURE_MASK_BNDCSR);
if (!bndcsr)
goto exit_trap;
+ trace_bounds_exception_mpx(bndcsr);
/*
* The error code field of the BNDSTATUS register communicates status
* information of a bound range exception #BR or operation involving
*/
switch (bndcsr->bndstatus & MPX_BNDSTA_ERROR_CODE) {
case 2: /* Bound directory has invalid entry. */
- if (mpx_handle_bd_fault(xsave_buf))
+ if (mpx_handle_bd_fault())
goto exit_trap;
break; /* Success, it was handled */
case 1: /* Bound violation. */
- info = mpx_generate_siginfo(regs, xsave_buf);
+ info = mpx_generate_siginfo(regs);
if (IS_ERR(info)) {
/*
* We failed to decode the MPX instruction. Act as if
die("bounds", regs, error_code);
}
-exit:
- exception_exit(prev_state);
return;
+
exit_trap:
/*
* This path out is for all the cases where we could not
* time..
*/
do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, NULL);
- exception_exit(prev_state);
}
dotraplinkage void
do_general_protection(struct pt_regs *regs, long error_code)
{
struct task_struct *tsk;
- enum ctx_state prev_state;
- prev_state = exception_enter();
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
conditional_sti(regs);
if (v8086_mode(regs)) {
local_irq_enable();
handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code);
- goto exit;
+ return;
}
tsk = current;
if (!user_mode(regs)) {
if (fixup_exception(regs))
- goto exit;
+ return;
tsk->thread.error_code = error_code;
tsk->thread.trap_nr = X86_TRAP_GP;
if (notify_die(DIE_GPF, "general protection fault", regs, error_code,
X86_TRAP_GP, SIGSEGV) != NOTIFY_STOP)
die("general protection fault", regs, error_code);
- goto exit;
+ return;
}
tsk->thread.error_code = error_code;
}
force_sig_info(SIGSEGV, SEND_SIG_PRIV, tsk);
-exit:
- exception_exit(prev_state);
}
NOKPROBE_SYMBOL(do_general_protection);
/* May run on IST stack. */
dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code)
{
- enum ctx_state prev_state;
-
#ifdef CONFIG_DYNAMIC_FTRACE
/*
* ftrace must be first, everything else may cause a recursive crash.
if (poke_int3_handler(regs))
return;
- prev_state = ist_enter(regs);
+ ist_enter(regs);
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP,
SIGTRAP) == NOTIFY_STOP)
* as we may switch to the interrupt stack.
*/
debug_stack_usage_inc();
- conditional_sti_ist(regs);
+ preempt_conditional_sti(regs);
do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, NULL);
- conditional_cli_ist(regs);
+ preempt_conditional_cli(regs);
debug_stack_usage_dec();
exit:
- ist_exit(regs, prev_state);
+ ist_exit(regs);
}
NOKPROBE_SYMBOL(do_int3);
dotraplinkage void do_debug(struct pt_regs *regs, long error_code)
{
struct task_struct *tsk = current;
- enum ctx_state prev_state;
int user_icebp = 0;
unsigned long dr6;
int si_code;
- prev_state = ist_enter(regs);
+ ist_enter(regs);
get_debugreg(dr6, 6);
debug_stack_usage_inc();
/* It's safe to allow irq's after DR6 has been saved */
- conditional_sti_ist(regs);
+ preempt_conditional_sti(regs);
if (v8086_mode(regs)) {
handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code,
X86_TRAP_DB);
- conditional_cli_ist(regs);
+ preempt_conditional_cli(regs);
debug_stack_usage_dec();
goto exit;
}
si_code = get_si_code(tsk->thread.debugreg6);
if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS) || user_icebp)
send_sigtrap(tsk, regs, error_code, si_code);
- conditional_cli_ist(regs);
+ preempt_conditional_cli(regs);
debug_stack_usage_dec();
exit:
- ist_exit(regs, prev_state);
+ ist_exit(regs);
}
NOKPROBE_SYMBOL(do_debug);
static void math_error(struct pt_regs *regs, int error_code, int trapnr)
{
struct task_struct *task = current;
+ struct fpu *fpu = &task->thread.fpu;
siginfo_t info;
- unsigned short err;
char *str = (trapnr == X86_TRAP_MF) ? "fpu exception" :
"simd exception";
return;
conditional_sti(regs);
- if (!user_mode(regs))
- {
+ if (!user_mode(regs)) {
if (!fixup_exception(regs)) {
task->thread.error_code = error_code;
task->thread.trap_nr = trapnr;
/*
* Save the info for the exception handler and clear the error.
*/
- unlazy_fpu(task);
- task->thread.trap_nr = trapnr;
+ fpu__save(fpu);
+
+ task->thread.trap_nr = trapnr;
task->thread.error_code = error_code;
- info.si_signo = SIGFPE;
- info.si_errno = 0;
- info.si_addr = (void __user *)uprobe_get_trap_addr(regs);
- if (trapnr == X86_TRAP_MF) {
- unsigned short cwd, swd;
- /*
- * (~cwd & swd) will mask out exceptions that are not set to unmasked
- * status. 0x3f is the exception bits in these regs, 0x200 is the
- * C1 reg you need in case of a stack fault, 0x040 is the stack
- * fault bit. We should only be taking one exception at a time,
- * so if this combination doesn't produce any single exception,
- * then we have a bad program that isn't synchronizing its FPU usage
- * and it will suffer the consequences since we won't be able to
- * fully reproduce the context of the exception
- */
- cwd = get_fpu_cwd(task);
- swd = get_fpu_swd(task);
+ info.si_signo = SIGFPE;
+ info.si_errno = 0;
+ info.si_addr = (void __user *)uprobe_get_trap_addr(regs);
- err = swd & ~cwd;
- } else {
- /*
- * The SIMD FPU exceptions are handled a little differently, as there
- * is only a single status/control register. Thus, to determine which
- * unmasked exception was caught we must mask the exception mask bits
- * at 0x1f80, and then use these to mask the exception bits at 0x3f.
- */
- unsigned short mxcsr = get_fpu_mxcsr(task);
- err = ~(mxcsr >> 7) & mxcsr;
- }
+ info.si_code = fpu__exception_code(fpu, trapnr);
- if (err & 0x001) { /* Invalid op */
- /*
- * swd & 0x240 == 0x040: Stack Underflow
- * swd & 0x240 == 0x240: Stack Overflow
- * User must clear the SF bit (0x40) if set
- */
- info.si_code = FPE_FLTINV;
- } else if (err & 0x004) { /* Divide by Zero */
- info.si_code = FPE_FLTDIV;
- } else if (err & 0x008) { /* Overflow */
- info.si_code = FPE_FLTOVF;
- } else if (err & 0x012) { /* Denormal, Underflow */
- info.si_code = FPE_FLTUND;
- } else if (err & 0x020) { /* Precision */
- info.si_code = FPE_FLTRES;
- } else {
- /*
- * If we're using IRQ 13, or supposedly even some trap
- * X86_TRAP_MF implementations, it's possible
- * we get a spurious trap, which is not an error.
- */
+ /* Retry when we get spurious exceptions: */
+ if (!info.si_code)
return;
- }
+
force_sig_info(SIGFPE, &info, task);
}
dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
{
- enum ctx_state prev_state;
-
- prev_state = exception_enter();
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
math_error(regs, error_code, X86_TRAP_MF);
- exception_exit(prev_state);
}
dotraplinkage void
do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
{
- enum ctx_state prev_state;
-
- prev_state = exception_enter();
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
math_error(regs, error_code, X86_TRAP_XF);
- exception_exit(prev_state);
}
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. */
- pr_info("Ignoring P6 Local APIC Spurious Interrupt Bug...\n");
-#endif
-}
-
-asmlinkage __visible void __attribute__((weak)) smp_thermal_interrupt(void)
-{
-}
-
-asmlinkage __visible void __attribute__((weak)) smp_threshold_interrupt(void)
-{
-}
-
-/*
- * 'math_state_restore()' saves the current math information in the
- * old math state array, and gets the new ones from the current task
- *
- * 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 (eg with local
- * local interrupts as in the case of do_device_not_available).
- */
-void math_state_restore(void)
-{
- struct task_struct *tsk = current;
-
- if (!tsk_used_math(tsk)) {
- local_irq_enable();
- /*
- * does a slab alloc which can sleep
- */
- if (init_fpu(tsk)) {
- /*
- * ran out of memory!
- */
- do_group_exit(SIGKILL);
- return;
- }
- local_irq_disable();
- }
-
- /* Avoid __kernel_fpu_begin() right after __thread_fpu_begin() */
- kernel_fpu_disable();
- __thread_fpu_begin(tsk);
- if (unlikely(restore_fpu_checking(tsk))) {
- fpu_reset_state(tsk);
- force_sig_info(SIGSEGV, SEND_SIG_PRIV, tsk);
- } else {
- tsk->thread.fpu_counter++;
- }
- kernel_fpu_enable();
}
-EXPORT_SYMBOL_GPL(math_state_restore);
dotraplinkage void
do_device_not_available(struct pt_regs *regs, long error_code)
{
- enum ctx_state prev_state;
-
- prev_state = exception_enter();
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
BUG_ON(use_eager_fpu());
#ifdef CONFIG_MATH_EMULATION
info.regs = regs;
math_emulate(&info);
- exception_exit(prev_state);
return;
}
#endif
- math_state_restore(); /* interrupts still off */
+ fpu__restore(¤t->thread.fpu); /* interrupts still off */
#ifdef CONFIG_X86_32
conditional_sti(regs);
#endif
- exception_exit(prev_state);
}
NOKPROBE_SYMBOL(do_device_not_available);
dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
{
siginfo_t info;
- enum ctx_state prev_state;
- prev_state = exception_enter();
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
local_irq_enable();
info.si_signo = SIGILL;
do_trap(X86_TRAP_IRET, SIGILL, "iret exception", regs, error_code,
&info);
}
- exception_exit(prev_state);
}
#endif
set_bit(i, used_vectors);
#ifdef CONFIG_IA32_EMULATION
- set_system_intr_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
+ set_system_intr_gate(IA32_SYSCALL_VECTOR, entry_INT80_compat);
set_bit(IA32_SYSCALL_VECTOR, used_vectors);
#endif
#ifdef CONFIG_X86_32
- set_system_trap_gate(SYSCALL_VECTOR, &system_call);
- set_bit(SYSCALL_VECTOR, used_vectors);
+ set_system_trap_gate(IA32_SYSCALL_VECTOR, entry_INT80_32);
+ set_bit(IA32_SYSCALL_VECTOR, used_vectors);
#endif
/*
Code Review / kvmfornfv.git / blobdiff