Commit eb05df9e authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cleanups from Peter Anvin:
 "The biggest textual change is the cleanup to use symbolic constants
  for x86 trap values.

  The only *functional* change and the reason for the x86/x32 dependency
  is the move of is_ia32_task() into <asm/thread_info.h> so that it can
  be used in other code that needs to understand if a system call comes
  from the compat entry point (and therefore uses i386 system call
  numbers) or not.  One intended user for that is the BPF system call
  filter.  Moving it out of <asm/compat.h> means we can define it
  unconditionally, returning always true on i386."

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Move is_ia32_task to asm/thread_info.h from asm/compat.h
  x86: Rename trap_no to trap_nr in thread_struct
  x86: Use enum instead of literals for trap values
parents a591afc0 ef334a20
......@@ -346,7 +346,7 @@ static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
put_user_ex(regs->dx, &sc->dx);
put_user_ex(regs->cx, &sc->cx);
put_user_ex(regs->ax, &sc->ax);
put_user_ex(current->thread.trap_no, &sc->trapno);
put_user_ex(current->thread.trap_nr, &sc->trapno);
put_user_ex(current->thread.error_code, &sc->err);
put_user_ex(regs->ip, &sc->ip);
put_user_ex(regs->cs, (unsigned int __user *)&sc->cs);
......
......@@ -235,15 +235,6 @@ static inline void __user *arch_compat_alloc_user_space(long len)
return (void __user *)round_down(sp - len, 16);
}
static inline bool is_ia32_task(void)
{
#ifdef CONFIG_IA32_EMULATION
if (current_thread_info()->status & TS_COMPAT)
return true;
#endif
return false;
}
static inline bool is_x32_task(void)
{
#ifdef CONFIG_X86_X32_ABI
......
......@@ -463,7 +463,7 @@ struct thread_struct {
unsigned long ptrace_dr7;
/* Fault info: */
unsigned long cr2;
unsigned long trap_no;
unsigned long trap_nr;
unsigned long error_code;
/* floating point and extended processor state */
struct fpu fpu;
......
......@@ -266,6 +266,18 @@ static inline void set_restore_sigmask(void)
ti->status |= TS_RESTORE_SIGMASK;
set_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags);
}
static inline bool is_ia32_task(void)
{
#ifdef CONFIG_X86_32
return true;
#endif
#ifdef CONFIG_IA32_EMULATION
if (current_thread_info()->status & TS_COMPAT)
return true;
#endif
return false;
}
#endif /* !__ASSEMBLY__ */
#ifndef __ASSEMBLY__
......
......@@ -89,4 +89,29 @@ asmlinkage void smp_thermal_interrupt(void);
asmlinkage void mce_threshold_interrupt(void);
#endif
/* Interrupts/Exceptions */
enum {
X86_TRAP_DE = 0, /* 0, Divide-by-zero */
X86_TRAP_DB, /* 1, Debug */
X86_TRAP_NMI, /* 2, Non-maskable Interrupt */
X86_TRAP_BP, /* 3, Breakpoint */
X86_TRAP_OF, /* 4, Overflow */
X86_TRAP_BR, /* 5, Bound Range Exceeded */
X86_TRAP_UD, /* 6, Invalid Opcode */
X86_TRAP_NM, /* 7, Device Not Available */
X86_TRAP_DF, /* 8, Double Fault */
X86_TRAP_OLD_MF, /* 9, Coprocessor Segment Overrun */
X86_TRAP_TS, /* 10, Invalid TSS */
X86_TRAP_NP, /* 11, Segment Not Present */
X86_TRAP_SS, /* 12, Stack Segment Fault */
X86_TRAP_GP, /* 13, General Protection Fault */
X86_TRAP_PF, /* 14, Page Fault */
X86_TRAP_SPURIOUS, /* 15, Spurious Interrupt */
X86_TRAP_MF, /* 16, x87 Floating-Point Exception */
X86_TRAP_AC, /* 17, Alignment Check */
X86_TRAP_MC, /* 18, Machine Check */
X86_TRAP_XF, /* 19, SIMD Floating-Point Exception */
X86_TRAP_IRET = 32, /* 32, IRET Exception */
};
#endif /* _ASM_X86_TRAPS_H */
......@@ -268,7 +268,7 @@ int __kprobes __die(const char *str, struct pt_regs *regs, long err)
#endif
printk("\n");
if (notify_die(DIE_OOPS, str, regs, err,
current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
current->thread.trap_nr, SIGSEGV) == NOTIFY_STOP)
return 1;
show_registers(regs);
......
......@@ -60,7 +60,7 @@ static irqreturn_t math_error_irq(int cpl, void *dev_id)
outb(0, 0xF0);
if (ignore_fpu_irq || !boot_cpu_data.hard_math)
return IRQ_NONE;
math_error(get_irq_regs(), 0, 16);
math_error(get_irq_regs(), 0, X86_TRAP_MF);
return IRQ_HANDLED;
}
......
......@@ -33,6 +33,7 @@
#include <asm/prctl.h>
#include <asm/proto.h>
#include <asm/hw_breakpoint.h>
#include <asm/traps.h>
#include "tls.h"
......@@ -1425,7 +1426,7 @@ static void fill_sigtrap_info(struct task_struct *tsk,
int error_code, int si_code,
struct siginfo *info)
{
tsk->thread.trap_no = 1;
tsk->thread.trap_nr = X86_TRAP_DB;
tsk->thread.error_code = error_code;
memset(info, 0, sizeof(*info));
......
......@@ -151,7 +151,7 @@ int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
put_user_ex(regs->r15, &sc->r15);
#endif /* CONFIG_X86_64 */
put_user_ex(current->thread.trap_no, &sc->trapno);
put_user_ex(current->thread.trap_nr, &sc->trapno);
put_user_ex(current->thread.error_code, &sc->err);
put_user_ex(regs->ip, &sc->ip);
#ifdef CONFIG_X86_32
......
......@@ -119,7 +119,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
* 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)
if (trapnr < X86_TRAP_UD)
goto vm86_trap;
goto trap_signal;
}
......@@ -132,7 +132,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
trap_signal:
#endif
/*
* We want error_code and trap_no set for userspace faults and
* We want error_code and trap_nr set for userspace faults and
* kernelspace faults which result in die(), but not
* kernelspace faults which are fixed up. die() gives the
* process no chance to handle the signal and notice the
......@@ -141,7 +141,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
* delivered, faults. See also do_general_protection below.
*/
tsk->thread.error_code = error_code;
tsk->thread.trap_no = trapnr;
tsk->thread.trap_nr = trapnr;
#ifdef CONFIG_X86_64
if (show_unhandled_signals && unhandled_signal(tsk, signr) &&
......@@ -164,7 +164,7 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs,
kernel_trap:
if (!fixup_exception(regs)) {
tsk->thread.error_code = error_code;
tsk->thread.trap_no = trapnr;
tsk->thread.trap_nr = trapnr;
die(str, regs, error_code);
}
return;
......@@ -203,27 +203,31 @@ dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
do_trap(trapnr, signr, str, regs, error_code, &info); \
}
DO_ERROR_INFO(0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->ip)
DO_ERROR(4, SIGSEGV, "overflow", overflow)
DO_ERROR(5, SIGSEGV, "bounds", bounds)
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)
DO_ERROR_INFO(X86_TRAP_DE, SIGFPE, "divide error", divide_error, FPE_INTDIV,
regs->ip)
DO_ERROR(X86_TRAP_OF, SIGSEGV, "overflow", overflow)
DO_ERROR(X86_TRAP_BR, SIGSEGV, "bounds", bounds)
DO_ERROR_INFO(X86_TRAP_UD, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN,
regs->ip)
DO_ERROR(X86_TRAP_OLD_MF, SIGFPE, "coprocessor segment overrun",
coprocessor_segment_overrun)
DO_ERROR(X86_TRAP_TS, SIGSEGV, "invalid TSS", invalid_TSS)
DO_ERROR(X86_TRAP_NP, SIGBUS, "segment not present", segment_not_present)
#ifdef CONFIG_X86_32
DO_ERROR(12, SIGBUS, "stack segment", stack_segment)
DO_ERROR(X86_TRAP_SS, SIGBUS, "stack segment", stack_segment)
#endif
DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
DO_ERROR_INFO(X86_TRAP_AC, 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)
X86_TRAP_SS, SIGBUS) == NOTIFY_STOP)
return;
preempt_conditional_sti(regs);
do_trap(12, SIGBUS, "stack segment", regs, error_code, NULL);
do_trap(X86_TRAP_SS, SIGBUS, "stack segment", regs, error_code, NULL);
preempt_conditional_cli(regs);
}
......@@ -233,10 +237,10 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
struct task_struct *tsk = current;
/* Return not checked because double check cannot be ignored */
notify_die(DIE_TRAP, str, regs, error_code, 8, SIGSEGV);
notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV);
tsk->thread.error_code = error_code;
tsk->thread.trap_no = 8;
tsk->thread.trap_nr = X86_TRAP_DF;
/*
* This is always a kernel trap and never fixable (and thus must
......@@ -264,7 +268,7 @@ do_general_protection(struct pt_regs *regs, long error_code)
goto gp_in_kernel;
tsk->thread.error_code = error_code;
tsk->thread.trap_no = 13;
tsk->thread.trap_nr = X86_TRAP_GP;
if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
printk_ratelimit()) {
......@@ -291,9 +295,9 @@ do_general_protection(struct pt_regs *regs, long error_code)
return;
tsk->thread.error_code = error_code;
tsk->thread.trap_no = 13;
if (notify_die(DIE_GPF, "general protection fault", regs,
error_code, 13, SIGSEGV) == NOTIFY_STOP)
tsk->thread.trap_nr = X86_TRAP_GP;
if (notify_die(DIE_GPF, "general protection fault", regs, error_code,
X86_TRAP_GP, SIGSEGV) == NOTIFY_STOP)
return;
die("general protection fault", regs, error_code);
}
......@@ -302,13 +306,13 @@ do_general_protection(struct pt_regs *regs, long error_code)
dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code)
{
#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
== NOTIFY_STOP)
if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP,
SIGTRAP) == NOTIFY_STOP)
return;
#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
== NOTIFY_STOP)
if (notify_die(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP,
SIGTRAP) == NOTIFY_STOP)
return;
/*
......@@ -317,7 +321,7 @@ dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code)
*/
debug_stack_usage_inc();
preempt_conditional_sti(regs);
do_trap(3, SIGTRAP, "int3", regs, error_code, NULL);
do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, NULL);
preempt_conditional_cli(regs);
debug_stack_usage_dec();
}
......@@ -422,8 +426,8 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)
preempt_conditional_sti(regs);
if (regs->flags & X86_VM_MASK) {
handle_vm86_trap((struct kernel_vm86_regs *) regs,
error_code, 1);
handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code,
X86_TRAP_DB);
preempt_conditional_cli(regs);
debug_stack_usage_dec();
return;
......@@ -460,7 +464,8 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr)
struct task_struct *task = current;
siginfo_t info;
unsigned short err;
char *str = (trapnr == 16) ? "fpu exception" : "simd exception";
char *str = (trapnr == X86_TRAP_MF) ? "fpu exception" :
"simd exception";
if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, SIGFPE) == NOTIFY_STOP)
return;
......@@ -470,7 +475,7 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr)
{
if (!fixup_exception(regs)) {
task->thread.error_code = error_code;
task->thread.trap_no = trapnr;
task->thread.trap_nr = trapnr;
die(str, regs, error_code);
}
return;
......@@ -480,12 +485,12 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr)
* Save the info for the exception handler and clear the error.
*/
save_init_fpu(task);
task->thread.trap_no = trapnr;
task->thread.trap_nr = trapnr;
task->thread.error_code = error_code;
info.si_signo = SIGFPE;
info.si_errno = 0;
info.si_addr = (void __user *)regs->ip;
if (trapnr == 16) {
if (trapnr == X86_TRAP_MF) {
unsigned short cwd, swd;
/*
* (~cwd & swd) will mask out exceptions that are not set to unmasked
......@@ -529,10 +534,11 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr)
info.si_code = FPE_FLTRES;
} else {
/*
* If we're using IRQ 13, or supposedly even some trap 16
* implementations, it's possible we get a spurious trap...
* 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.
*/
return; /* Spurious trap, no error */
return;
}
force_sig_info(SIGFPE, &info, task);
}
......@@ -543,13 +549,13 @@ dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code)
ignore_fpu_irq = 1;
#endif
math_error(regs, error_code, 16);
math_error(regs, error_code, X86_TRAP_MF);
}
dotraplinkage void
do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
{
math_error(regs, error_code, 19);
math_error(regs, error_code, X86_TRAP_XF);
}
dotraplinkage void
......@@ -643,20 +649,21 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
info.si_errno = 0;
info.si_code = ILL_BADSTK;
info.si_addr = NULL;
if (notify_die(DIE_TRAP, "iret exception",
regs, error_code, 32, SIGILL) == NOTIFY_STOP)
if (notify_die(DIE_TRAP, "iret exception", regs, error_code,
X86_TRAP_IRET, SIGILL) == NOTIFY_STOP)
return;
do_trap(32, SIGILL, "iret exception", regs, error_code, &info);
do_trap(X86_TRAP_IRET, SIGILL, "iret exception", regs, error_code,
&info);
}
#endif
/* Set of traps needed for early debugging. */
void __init early_trap_init(void)
{
set_intr_gate_ist(1, &debug, DEBUG_STACK);
set_intr_gate_ist(X86_TRAP_DB, &debug, DEBUG_STACK);
/* int3 can be called from all */
set_system_intr_gate_ist(3, &int3, DEBUG_STACK);
set_intr_gate(14, &page_fault);
set_system_intr_gate_ist(X86_TRAP_BP, &int3, DEBUG_STACK);
set_intr_gate(X86_TRAP_PF, &page_fault);
load_idt(&idt_descr);
}
......@@ -672,30 +679,30 @@ void __init trap_init(void)
early_iounmap(p, 4);
#endif
set_intr_gate(0, &divide_error);
set_intr_gate_ist(2, &nmi, NMI_STACK);
set_intr_gate(X86_TRAP_DE, &divide_error);
set_intr_gate_ist(X86_TRAP_NMI, &nmi, NMI_STACK);
/* int4 can be called from all */
set_system_intr_gate(4, &overflow);
set_intr_gate(5, &bounds);
set_intr_gate(6, &invalid_op);
set_intr_gate(7, &device_not_available);
set_system_intr_gate(X86_TRAP_OF, &overflow);
set_intr_gate(X86_TRAP_BR, &bounds);
set_intr_gate(X86_TRAP_UD, &invalid_op);
set_intr_gate(X86_TRAP_NM, &device_not_available);
#ifdef CONFIG_X86_32
set_task_gate(8, GDT_ENTRY_DOUBLEFAULT_TSS);
set_task_gate(X86_TRAP_DF, GDT_ENTRY_DOUBLEFAULT_TSS);
#else
set_intr_gate_ist(8, &double_fault, DOUBLEFAULT_STACK);
set_intr_gate_ist(X86_TRAP_DF, &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);
set_intr_gate_ist(12, &stack_segment, STACKFAULT_STACK);
set_intr_gate(13, &general_protection);
set_intr_gate(15, &spurious_interrupt_bug);
set_intr_gate(16, &coprocessor_error);
set_intr_gate(17, &alignment_check);
set_intr_gate(X86_TRAP_OLD_MF, &coprocessor_segment_overrun);
set_intr_gate(X86_TRAP_TS, &invalid_TSS);
set_intr_gate(X86_TRAP_NP, &segment_not_present);
set_intr_gate_ist(X86_TRAP_SS, &stack_segment, STACKFAULT_STACK);
set_intr_gate(X86_TRAP_GP, &general_protection);
set_intr_gate(X86_TRAP_SPURIOUS, &spurious_interrupt_bug);
set_intr_gate(X86_TRAP_MF, &coprocessor_error);
set_intr_gate(X86_TRAP_AC, &alignment_check);
#ifdef CONFIG_X86_MCE
set_intr_gate_ist(18, &machine_check, MCE_STACK);
set_intr_gate_ist(X86_TRAP_MC, &machine_check, MCE_STACK);
#endif
set_intr_gate(19, &simd_coprocessor_error);
set_intr_gate(X86_TRAP_XF, &simd_coprocessor_error);
/* Reserve all the builtin and the syscall vector: */
for (i = 0; i < FIRST_EXTERNAL_VECTOR; i++)
......@@ -720,7 +727,7 @@ void __init trap_init(void)
#ifdef CONFIG_X86_64
memcpy(&nmi_idt_table, &idt_table, IDT_ENTRIES * 16);
set_nmi_gate(1, &debug);
set_nmi_gate(3, &int3);
set_nmi_gate(X86_TRAP_DB, &debug);
set_nmi_gate(X86_TRAP_BP, &int3);
#endif
}
......@@ -569,7 +569,7 @@ int handle_vm86_trap(struct kernel_vm86_regs *regs, long error_code, int trapno)
}
if (trapno != 1)
return 1; /* we let this handle by the calling routine */
current->thread.trap_no = trapno;
current->thread.trap_nr = trapno;
current->thread.error_code = error_code;
force_sig(SIGTRAP, current);
return 0;
......
......@@ -152,7 +152,7 @@ static bool write_ok_or_segv(unsigned long ptr, size_t size)
thread->error_code = 6; /* user fault, no page, write */
thread->cr2 = ptr;
thread->trap_no = 14;
thread->trap_nr = X86_TRAP_PF;
memset(&info, 0, sizeof(info));
info.si_signo = SIGSEGV;
......
......@@ -28,6 +28,7 @@
#include <linux/regset.h>
#include <asm/uaccess.h>
#include <asm/traps.h>
#include <asm/desc.h>
#include <asm/user.h>
#include <asm/i387.h>
......@@ -269,7 +270,7 @@ void math_emulate(struct math_emu_info *info)
FPU_EIP = FPU_ORIG_EIP; /* Point to current FPU instruction. */
RE_ENTRANT_CHECK_OFF;
current->thread.trap_no = 16;
current->thread.trap_nr = X86_TRAP_MF;
current->thread.error_code = 0;
send_sig(SIGFPE, current, 1);
return;
......@@ -662,7 +663,7 @@ static int valid_prefix(u_char *Byte, u_char __user **fpu_eip,
void math_abort(struct math_emu_info *info, unsigned int signal)
{
FPU_EIP = FPU_ORIG_EIP;
current->thread.trap_no = 16;
current->thread.trap_nr = X86_TRAP_MF;
current->thread.error_code = 0;
send_sig(signal, current, 1);
RE_ENTRANT_CHECK_OFF;
......
......@@ -615,7 +615,7 @@ pgtable_bad(struct pt_regs *regs, unsigned long error_code,
dump_pagetable(address);
tsk->thread.cr2 = address;
tsk->thread.trap_no = 14;
tsk->thread.trap_nr = X86_TRAP_PF;
tsk->thread.error_code = error_code;
if (__die("Bad pagetable", regs, error_code))
......@@ -636,7 +636,7 @@ no_context(struct pt_regs *regs, unsigned long error_code,
/* Are we prepared to handle this kernel fault? */
if (fixup_exception(regs)) {
if (current_thread_info()->sig_on_uaccess_error && signal) {
tsk->thread.trap_no = 14;
tsk->thread.trap_nr = X86_TRAP_PF;
tsk->thread.error_code = error_code | PF_USER;
tsk->thread.cr2 = address;
......@@ -676,7 +676,7 @@ no_context(struct pt_regs *regs, unsigned long error_code,
printk(KERN_EMERG "Thread overran stack, or stack corrupted\n");
tsk->thread.cr2 = address;
tsk->thread.trap_no = 14;
tsk->thread.trap_nr = X86_TRAP_PF;
tsk->thread.error_code = error_code;
sig = SIGKILL;
......@@ -754,7 +754,7 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code,
/* Kernel addresses are always protection faults: */
tsk->thread.cr2 = address;
tsk->thread.error_code = error_code | (address >= TASK_SIZE);
tsk->thread.trap_no = 14;
tsk->thread.trap_nr = X86_TRAP_PF;
force_sig_info_fault(SIGSEGV, si_code, address, tsk, 0);
......@@ -838,7 +838,7 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
tsk->thread.cr2 = address;
tsk->thread.error_code = error_code;
tsk->thread.trap_no = 14;
tsk->thread.trap_nr = X86_TRAP_PF;
#ifdef CONFIG_MEMORY_FAILURE
if (fault & (VM_FAULT_HWPOISON|VM_FAULT_HWPOISON_LARGE)) {
......
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