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-rw-r--r--arch/x86/kernel/Makefile2
-rw-r--r--arch/x86/kernel/asm-offsets_32.c9
-rw-r--r--arch/x86/kernel/asm-offsets_64.c36
-rw-r--r--arch/x86/kernel/cpu/mce/core.c12
-rw-r--r--arch/x86/kernel/cpu/mce/internal.h3
-rw-r--r--arch/x86/kernel/irq.c3
-rw-r--r--arch/x86/kernel/ldt.c1
-rw-r--r--arch/x86/kernel/process.c1
-rw-r--r--arch/x86/kernel/process_32.c1
-rw-r--r--arch/x86/kernel/process_64.c1
-rw-r--r--arch/x86/kernel/signal.c4
-rw-r--r--arch/x86/kernel/sys_ia32.c255
-rw-r--r--arch/x86/kernel/sys_x86_64.c1
-rw-r--r--arch/x86/kernel/traps.c41
14 files changed, 306 insertions, 64 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 8be5926cce51..bb5abfef0256 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -52,6 +52,8 @@ obj-y += setup.o x86_init.o i8259.o irqinit.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o
obj-$(CONFIG_IRQ_WORK) += irq_work.o
obj-y += probe_roms.o
+obj-$(CONFIG_X86_32) += sys_ia32.o
+obj-$(CONFIG_IA32_EMULATION) += sys_ia32.o
obj-$(CONFIG_X86_64) += sys_x86_64.o
obj-$(CONFIG_X86_ESPFIX64) += espfix_64.o
obj-$(CONFIG_SYSFS) += ksysfs.o
diff --git a/arch/x86/kernel/asm-offsets_32.c b/arch/x86/kernel/asm-offsets_32.c
index 2b4256ebe86e..6e043f295a60 100644
--- a/arch/x86/kernel/asm-offsets_32.c
+++ b/arch/x86/kernel/asm-offsets_32.c
@@ -7,11 +7,6 @@
#include <asm/ucontext.h>
-#define __SYSCALL_I386(nr, sym, qual) [nr] = 1,
-static char syscalls[] = {
-#include <asm/syscalls_32.h>
-};
-
/* workaround for a warning with -Wmissing-prototypes */
void foo(void);
@@ -64,9 +59,5 @@ void foo(void)
#endif
BLANK();
- DEFINE(__NR_syscall_max, sizeof(syscalls) - 1);
- DEFINE(NR_syscalls, sizeof(syscalls));
-
- BLANK();
DEFINE(EFI_svam, offsetof(efi_runtime_services_t, set_virtual_address_map));
}
diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c
index 24d2fde30d00..c2a47016f243 100644
--- a/arch/x86/kernel/asm-offsets_64.c
+++ b/arch/x86/kernel/asm-offsets_64.c
@@ -5,30 +5,6 @@
#include <asm/ia32.h>
-#define __SYSCALL_64(nr, sym, qual) [nr] = 1,
-#define __SYSCALL_X32(nr, sym, qual)
-static char syscalls_64[] = {
-#include <asm/syscalls_64.h>
-};
-#undef __SYSCALL_64
-#undef __SYSCALL_X32
-
-#ifdef CONFIG_X86_X32_ABI
-#define __SYSCALL_64(nr, sym, qual)
-#define __SYSCALL_X32(nr, sym, qual) [nr] = 1,
-static char syscalls_x32[] = {
-#include <asm/syscalls_64.h>
-};
-#undef __SYSCALL_64
-#undef __SYSCALL_X32
-#endif
-
-#define __SYSCALL_I386(nr, sym, qual) [nr] = 1,
-static char syscalls_ia32[] = {
-#include <asm/syscalls_32.h>
-};
-#undef __SYSCALL_I386
-
#if defined(CONFIG_KVM_GUEST) && defined(CONFIG_PARAVIRT_SPINLOCKS)
#include <asm/kvm_para.h>
#endif
@@ -90,17 +66,5 @@ int main(void)
DEFINE(stack_canary_offset, offsetof(struct fixed_percpu_data, stack_canary));
BLANK();
#endif
-
- DEFINE(__NR_syscall_max, sizeof(syscalls_64) - 1);
- DEFINE(NR_syscalls, sizeof(syscalls_64));
-
-#ifdef CONFIG_X86_X32_ABI
- DEFINE(__NR_syscall_x32_max, sizeof(syscalls_x32) - 1);
- DEFINE(X32_NR_syscalls, sizeof(syscalls_x32));
-#endif
-
- DEFINE(__NR_syscall_compat_max, sizeof(syscalls_ia32) - 1);
- DEFINE(IA32_NR_syscalls, sizeof(syscalls_ia32));
-
return 0;
}
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index dd06fce537fc..54165f3569e8 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1215,8 +1215,14 @@ static void __mc_scan_banks(struct mce *m, struct mce *final,
* On Intel systems this is entered on all CPUs in parallel through
* MCE broadcast. However some CPUs might be broken beyond repair,
* so be always careful when synchronizing with others.
+ *
+ * Tracing and kprobes are disabled: if we interrupted a kernel context
+ * with IF=1, we need to minimize stack usage. There are also recursion
+ * issues: if the machine check was due to a failure of the memory
+ * backing the user stack, tracing that reads the user stack will cause
+ * potentially infinite recursion.
*/
-void do_machine_check(struct pt_regs *regs, long error_code)
+void notrace do_machine_check(struct pt_regs *regs, long error_code)
{
DECLARE_BITMAP(valid_banks, MAX_NR_BANKS);
DECLARE_BITMAP(toclear, MAX_NR_BANKS);
@@ -1362,6 +1368,7 @@ out_ist:
ist_exit(regs);
}
EXPORT_SYMBOL_GPL(do_machine_check);
+NOKPROBE_SYMBOL(do_machine_check);
#ifndef CONFIG_MEMORY_FAILURE
int memory_failure(unsigned long pfn, int flags)
@@ -1896,10 +1903,11 @@ static void unexpected_machine_check(struct pt_regs *regs, long error_code)
void (*machine_check_vector)(struct pt_regs *, long error_code) =
unexpected_machine_check;
-dotraplinkage void do_mce(struct pt_regs *regs, long error_code)
+dotraplinkage notrace void do_mce(struct pt_regs *regs, long error_code)
{
machine_check_vector(regs, error_code);
}
+NOKPROBE_SYMBOL(do_mce);
/*
* Called for each booted CPU to set up machine checks.
diff --git a/arch/x86/kernel/cpu/mce/internal.h b/arch/x86/kernel/cpu/mce/internal.h
index 97db18441d2c..3b008172ad73 100644
--- a/arch/x86/kernel/cpu/mce/internal.h
+++ b/arch/x86/kernel/cpu/mce/internal.h
@@ -8,6 +8,9 @@
#include <linux/device.h>
#include <asm/mce.h>
+/* Pointer to the installed machine check handler for this CPU setup. */
+extern void (*machine_check_vector)(struct pt_regs *, long error_code);
+
enum severity_level {
MCE_NO_SEVERITY,
MCE_DEFERRED_SEVERITY,
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 21efee32e2b1..c7965ff429c5 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -230,7 +230,7 @@ u64 arch_irq_stat(void)
* SMP cross-CPU interrupts have their own specific
* handlers).
*/
-__visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
+__visible void __irq_entry do_IRQ(struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
struct irq_desc * desc;
@@ -263,7 +263,6 @@ __visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
exiting_irq();
set_irq_regs(old_regs);
- return 1;
}
#ifdef CONFIG_X86_LOCAL_APIC
diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index c57e1ca70fd1..84c3ba32f211 100644
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -27,7 +27,6 @@
#include <asm/tlb.h>
#include <asm/desc.h>
#include <asm/mmu_context.h>
-#include <asm/syscalls.h>
#include <asm/pgtable_areas.h>
/* This is a multiple of PAGE_SIZE. */
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 3053c85e0e42..8a59dae23868 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -28,7 +28,6 @@
#include <linux/hw_breakpoint.h>
#include <asm/cpu.h>
#include <asm/apic.h>
-#include <asm/syscalls.h>
#include <linux/uaccess.h>
#include <asm/mwait.h>
#include <asm/fpu/internal.h>
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 5052ced43373..954b013cc585 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -49,7 +49,6 @@
#include <asm/tlbflush.h>
#include <asm/cpu.h>
-#include <asm/syscalls.h>
#include <asm/debugreg.h>
#include <asm/switch_to.h>
#include <asm/vm86.h>
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index ffd497804dbc..5ef9d8f25b0e 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -48,7 +48,6 @@
#include <asm/desc.h>
#include <asm/proto.h>
#include <asm/ia32.h>
-#include <asm/syscalls.h>
#include <asm/debugreg.h>
#include <asm/switch_to.h>
#include <asm/xen/hypervisor.h>
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 8a29573851a3..0364f8c3bee3 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -42,8 +42,6 @@
#endif /* CONFIG_X86_64 */
#include <asm/syscall.h>
-#include <asm/syscalls.h>
-
#include <asm/sigframe.h>
#include <asm/signal.h>
@@ -859,7 +857,7 @@ void signal_fault(struct pt_regs *regs, void __user *frame, char *where)
}
#ifdef CONFIG_X86_X32_ABI
-asmlinkage long sys32_x32_rt_sigreturn(void)
+COMPAT_SYSCALL_DEFINE0(x32_rt_sigreturn)
{
struct pt_regs *regs = current_pt_regs();
struct rt_sigframe_x32 __user *frame;
diff --git a/arch/x86/kernel/sys_ia32.c b/arch/x86/kernel/sys_ia32.c
new file mode 100644
index 000000000000..ab03fede1422
--- /dev/null
+++ b/arch/x86/kernel/sys_ia32.c
@@ -0,0 +1,255 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * sys_ia32.c: Conversion between 32bit and 64bit native syscalls. Based on
+ * sys_sparc32
+ *
+ * Copyright (C) 2000 VA Linux Co
+ * Copyright (C) 2000 Don Dugger <n0ano@valinux.com>
+ * Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com>
+ * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 2000 Hewlett-Packard Co.
+ * Copyright (C) 2000 David Mosberger-Tang <davidm@hpl.hp.com>
+ * Copyright (C) 2000,2001,2002 Andi Kleen, SuSE Labs (x86-64 port)
+ *
+ * These routines maintain argument size conversion between 32bit and 64bit
+ * environment. In 2.5 most of this should be moved to a generic directory.
+ *
+ * This file assumes that there is a hole at the end of user address space.
+ *
+ * Some of the functions are LE specific currently. These are
+ * hopefully all marked. This should be fixed.
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/signal.h>
+#include <linux/syscalls.h>
+#include <linux/times.h>
+#include <linux/utsname.h>
+#include <linux/mm.h>
+#include <linux/uio.h>
+#include <linux/poll.h>
+#include <linux/personality.h>
+#include <linux/stat.h>
+#include <linux/rwsem.h>
+#include <linux/compat.h>
+#include <linux/vfs.h>
+#include <linux/ptrace.h>
+#include <linux/highuid.h>
+#include <linux/sysctl.h>
+#include <linux/slab.h>
+#include <linux/sched/task.h>
+#include <asm/mman.h>
+#include <asm/types.h>
+#include <linux/uaccess.h>
+#include <linux/atomic.h>
+#include <asm/vgtod.h>
+#include <asm/ia32.h>
+
+#define AA(__x) ((unsigned long)(__x))
+
+SYSCALL_DEFINE3(ia32_truncate64, const char __user *, filename,
+ unsigned long, offset_low, unsigned long, offset_high)
+{
+ return ksys_truncate(filename,
+ ((loff_t) offset_high << 32) | offset_low);
+}
+
+SYSCALL_DEFINE3(ia32_ftruncate64, unsigned int, fd,
+ unsigned long, offset_low, unsigned long, offset_high)
+{
+ return ksys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low);
+}
+
+/* warning: next two assume little endian */
+SYSCALL_DEFINE5(ia32_pread64, unsigned int, fd, char __user *, ubuf,
+ u32, count, u32, poslo, u32, poshi)
+{
+ return ksys_pread64(fd, ubuf, count,
+ ((loff_t)AA(poshi) << 32) | AA(poslo));
+}
+
+SYSCALL_DEFINE5(ia32_pwrite64, unsigned int, fd, const char __user *, ubuf,
+ u32, count, u32, poslo, u32, poshi)
+{
+ return ksys_pwrite64(fd, ubuf, count,
+ ((loff_t)AA(poshi) << 32) | AA(poslo));
+}
+
+
+/*
+ * Some system calls that need sign extended arguments. This could be
+ * done by a generic wrapper.
+ */
+SYSCALL_DEFINE6(ia32_fadvise64_64, int, fd, __u32, offset_low,
+ __u32, offset_high, __u32, len_low, __u32, len_high,
+ int, advice)
+{
+ return ksys_fadvise64_64(fd,
+ (((u64)offset_high)<<32) | offset_low,
+ (((u64)len_high)<<32) | len_low,
+ advice);
+}
+
+SYSCALL_DEFINE4(ia32_readahead, int, fd, unsigned int, off_lo,
+ unsigned int, off_hi, size_t, count)
+{
+ return ksys_readahead(fd, ((u64)off_hi << 32) | off_lo, count);
+}
+
+SYSCALL_DEFINE6(ia32_sync_file_range, int, fd, unsigned int, off_low,
+ unsigned int, off_hi, unsigned int, n_low,
+ unsigned int, n_hi, int, flags)
+{
+ return ksys_sync_file_range(fd,
+ ((u64)off_hi << 32) | off_low,
+ ((u64)n_hi << 32) | n_low, flags);
+}
+
+SYSCALL_DEFINE5(ia32_fadvise64, int, fd, unsigned int, offset_lo,
+ unsigned int, offset_hi, size_t, len, int, advice)
+{
+ return ksys_fadvise64_64(fd, ((u64)offset_hi << 32) | offset_lo,
+ len, advice);
+}
+
+SYSCALL_DEFINE6(ia32_fallocate, int, fd, int, mode,
+ unsigned int, offset_lo, unsigned int, offset_hi,
+ unsigned int, len_lo, unsigned int, len_hi)
+{
+ return ksys_fallocate(fd, mode, ((u64)offset_hi << 32) | offset_lo,
+ ((u64)len_hi << 32) | len_lo);
+}
+
+#ifdef CONFIG_IA32_EMULATION
+/*
+ * Another set for IA32/LFS -- x86_64 struct stat is different due to
+ * support for 64bit inode numbers.
+ */
+static int cp_stat64(struct stat64 __user *ubuf, struct kstat *stat)
+{
+ typeof(ubuf->st_uid) uid = 0;
+ typeof(ubuf->st_gid) gid = 0;
+ SET_UID(uid, from_kuid_munged(current_user_ns(), stat->uid));
+ SET_GID(gid, from_kgid_munged(current_user_ns(), stat->gid));
+ if (!access_ok(ubuf, sizeof(struct stat64)) ||
+ __put_user(huge_encode_dev(stat->dev), &ubuf->st_dev) ||
+ __put_user(stat->ino, &ubuf->__st_ino) ||
+ __put_user(stat->ino, &ubuf->st_ino) ||
+ __put_user(stat->mode, &ubuf->st_mode) ||
+ __put_user(stat->nlink, &ubuf->st_nlink) ||
+ __put_user(uid, &ubuf->st_uid) ||
+ __put_user(gid, &ubuf->st_gid) ||
+ __put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev) ||
+ __put_user(stat->size, &ubuf->st_size) ||
+ __put_user(stat->atime.tv_sec, &ubuf->st_atime) ||
+ __put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec) ||
+ __put_user(stat->mtime.tv_sec, &ubuf->st_mtime) ||
+ __put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
+ __put_user(stat->ctime.tv_sec, &ubuf->st_ctime) ||
+ __put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
+ __put_user(stat->blksize, &ubuf->st_blksize) ||
+ __put_user(stat->blocks, &ubuf->st_blocks))
+ return -EFAULT;
+ return 0;
+}
+
+COMPAT_SYSCALL_DEFINE2(ia32_stat64, const char __user *, filename,
+ struct stat64 __user *, statbuf)
+{
+ struct kstat stat;
+ int ret = vfs_stat(filename, &stat);
+
+ if (!ret)
+ ret = cp_stat64(statbuf, &stat);
+ return ret;
+}
+
+COMPAT_SYSCALL_DEFINE2(ia32_lstat64, const char __user *, filename,
+ struct stat64 __user *, statbuf)
+{
+ struct kstat stat;
+ int ret = vfs_lstat(filename, &stat);
+ if (!ret)
+ ret = cp_stat64(statbuf, &stat);
+ return ret;
+}
+
+COMPAT_SYSCALL_DEFINE2(ia32_fstat64, unsigned int, fd,
+ struct stat64 __user *, statbuf)
+{
+ struct kstat stat;
+ int ret = vfs_fstat(fd, &stat);
+ if (!ret)
+ ret = cp_stat64(statbuf, &stat);
+ return ret;
+}
+
+COMPAT_SYSCALL_DEFINE4(ia32_fstatat64, unsigned int, dfd,
+ const char __user *, filename,
+ struct stat64 __user *, statbuf, int, flag)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_fstatat(dfd, filename, &stat, flag);
+ if (error)
+ return error;
+ return cp_stat64(statbuf, &stat);
+}
+
+/*
+ * Linux/i386 didn't use to be able to handle more than
+ * 4 system call parameters, so these system calls used a memory
+ * block for parameter passing..
+ */
+
+struct mmap_arg_struct32 {
+ unsigned int addr;
+ unsigned int len;
+ unsigned int prot;
+ unsigned int flags;
+ unsigned int fd;
+ unsigned int offset;
+};
+
+COMPAT_SYSCALL_DEFINE1(ia32_mmap, struct mmap_arg_struct32 __user *, arg)
+{
+ struct mmap_arg_struct32 a;
+
+ if (copy_from_user(&a, arg, sizeof(a)))
+ return -EFAULT;
+
+ if (a.offset & ~PAGE_MASK)
+ return -EINVAL;
+
+ return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
+ a.offset>>PAGE_SHIFT);
+}
+
+/*
+ * The 32-bit clone ABI is CONFIG_CLONE_BACKWARDS
+ */
+COMPAT_SYSCALL_DEFINE5(ia32_clone, unsigned long, clone_flags,
+ unsigned long, newsp, int __user *, parent_tidptr,
+ unsigned long, tls_val, int __user *, child_tidptr)
+{
+ struct kernel_clone_args args = {
+ .flags = (clone_flags & ~CSIGNAL),
+ .pidfd = parent_tidptr,
+ .child_tid = child_tidptr,
+ .parent_tid = parent_tidptr,
+ .exit_signal = (clone_flags & CSIGNAL),
+ .stack = newsp,
+ .tls = tls_val,
+ };
+
+ if (!legacy_clone_args_valid(&args))
+ return -EINVAL;
+
+ return _do_fork(&args);
+}
+#endif /* CONFIG_IA32_EMULATION */
diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c
index ca3c11a17b5a..504fa5425bce 100644
--- a/arch/x86/kernel/sys_x86_64.c
+++ b/arch/x86/kernel/sys_x86_64.c
@@ -21,7 +21,6 @@
#include <asm/elf.h>
#include <asm/ia32.h>
-#include <asm/syscalls.h>
/*
* Align a virtual address to avoid aliasing in the I$ on AMD F15h.
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 6ef00eb6fbb9..c0bc9df8634d 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -572,14 +572,20 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code)
return;
/*
- * Use ist_enter despite the fact that we don't use an IST stack.
- * We can be called from a kprobe in non-CONTEXT_KERNEL kernel
- * mode or even during context tracking state changes.
+ * Unlike any other non-IST entry, we can be called from a kprobe in
+ * non-CONTEXT_KERNEL kernel mode or even during context tracking
+ * state changes. Make sure that we wake up RCU even if we're coming
+ * from kernel code.
*
- * This means that we can't schedule. That's okay.
+ * This means that we can't schedule even if we came from a
+ * preemptible kernel context. That's okay.
*/
- ist_enter(regs);
+ if (!user_mode(regs)) {
+ rcu_nmi_enter();
+ preempt_disable();
+ }
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)
@@ -600,7 +606,10 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code)
cond_local_irq_disable(regs);
exit:
- ist_exit(regs);
+ if (!user_mode(regs)) {
+ preempt_enable_no_resched();
+ rcu_nmi_exit();
+ }
}
NOKPROBE_SYMBOL(do_int3);
@@ -862,7 +871,25 @@ do_simd_coprocessor_error(struct pt_regs *regs, long error_code)
dotraplinkage void
do_spurious_interrupt_bug(struct pt_regs *regs, long error_code)
{
- cond_local_irq_enable(regs);
+ /*
+ * This addresses a Pentium Pro Erratum:
+ *
+ * PROBLEM: If the APIC subsystem is configured in mixed mode with
+ * Virtual Wire mode implemented through the local APIC, an
+ * interrupt vector of 0Fh (Intel reserved encoding) may be
+ * generated by the local APIC (Int 15). This vector may be
+ * generated upon receipt of a spurious interrupt (an interrupt
+ * which is removed before the system receives the INTA sequence)
+ * instead of the programmed 8259 spurious interrupt vector.
+ *
+ * IMPLICATION: The spurious interrupt vector programmed in the
+ * 8259 is normally handled by an operating system's spurious
+ * interrupt handler. However, a vector of 0Fh is unknown to some
+ * operating systems, which would crash if this erratum occurred.
+ *
+ * In theory this could be limited to 32bit, but the handler is not
+ * hurting and who knows which other CPUs suffer from this.
+ */
}
dotraplinkage void