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Diffstat (limited to 'arch/powerpc/kernel/traps.c')
-rw-r--r--arch/powerpc/kernel/traps.c119
1 files changed, 97 insertions, 22 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 83efa2f7d92..c0e5caf8ccc 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -35,6 +35,7 @@
#include <linux/kdebug.h>
#include <linux/debugfs.h>
#include <linux/ratelimit.h>
+#include <linux/context_tracking.h>
#include <asm/emulated_ops.h>
#include <asm/pgtable.h>
@@ -52,6 +53,7 @@
#ifdef CONFIG_PPC64
#include <asm/firmware.h>
#include <asm/processor.h>
+#include <asm/tm.h>
#endif
#include <asm/kexec.h>
#include <asm/ppc-opcode.h>
@@ -667,6 +669,7 @@ int machine_check_generic(struct pt_regs *regs)
void machine_check_exception(struct pt_regs *regs)
{
+ enum ctx_state prev_state = exception_enter();
int recover = 0;
__get_cpu_var(irq_stat).mce_exceptions++;
@@ -683,7 +686,7 @@ void machine_check_exception(struct pt_regs *regs)
recover = cur_cpu_spec->machine_check(regs);
if (recover > 0)
- return;
+ goto bail;
#if defined(CONFIG_8xx) && defined(CONFIG_PCI)
/* the qspan pci read routines can cause machine checks -- Cort
@@ -693,20 +696,23 @@ void machine_check_exception(struct pt_regs *regs)
* -- BenH
*/
bad_page_fault(regs, regs->dar, SIGBUS);
- return;
+ goto bail;
#endif
if (debugger_fault_handler(regs))
- return;
+ goto bail;
if (check_io_access(regs))
- return;
+ goto bail;
die("Machine check", regs, SIGBUS);
/* Must die if the interrupt is not recoverable */
if (!(regs->msr & MSR_RI))
panic("Unrecoverable Machine check");
+
+bail:
+ exception_exit(prev_state);
}
void SMIException(struct pt_regs *regs)
@@ -716,20 +722,29 @@ void SMIException(struct pt_regs *regs)
void unknown_exception(struct pt_regs *regs)
{
+ enum ctx_state prev_state = exception_enter();
+
printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
regs->nip, regs->msr, regs->trap);
_exception(SIGTRAP, regs, 0, 0);
+
+ exception_exit(prev_state);
}
void instruction_breakpoint_exception(struct pt_regs *regs)
{
+ enum ctx_state prev_state = exception_enter();
+
if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5,
5, SIGTRAP) == NOTIFY_STOP)
- return;
+ goto bail;
if (debugger_iabr_match(regs))
- return;
+ goto bail;
_exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
+
+bail:
+ exception_exit(prev_state);
}
void RunModeException(struct pt_regs *regs)
@@ -739,15 +754,20 @@ void RunModeException(struct pt_regs *regs)
void __kprobes single_step_exception(struct pt_regs *regs)
{
+ enum ctx_state prev_state = exception_enter();
+
clear_single_step(regs);
if (notify_die(DIE_SSTEP, "single_step", regs, 5,
5, SIGTRAP) == NOTIFY_STOP)
- return;
+ goto bail;
if (debugger_sstep(regs))
- return;
+ goto bail;
_exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
+
+bail:
+ exception_exit(prev_state);
}
/*
@@ -913,6 +933,28 @@ static int emulate_isel(struct pt_regs *regs, u32 instword)
return 0;
}
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+static inline bool tm_abort_check(struct pt_regs *regs, int cause)
+{
+ /* If we're emulating a load/store in an active transaction, we cannot
+ * emulate it as the kernel operates in transaction suspended context.
+ * We need to abort the transaction. This creates a persistent TM
+ * abort so tell the user what caused it with a new code.
+ */
+ if (MSR_TM_TRANSACTIONAL(regs->msr)) {
+ tm_enable();
+ tm_abort(cause);
+ return true;
+ }
+ return false;
+}
+#else
+static inline bool tm_abort_check(struct pt_regs *regs, int reason)
+{
+ return false;
+}
+#endif
+
static int emulate_instruction(struct pt_regs *regs)
{
u32 instword;
@@ -952,6 +994,9 @@ static int emulate_instruction(struct pt_regs *regs)
/* Emulate load/store string insn. */
if ((instword & PPC_INST_STRING_GEN_MASK) == PPC_INST_STRING) {
+ if (tm_abort_check(regs,
+ TM_CAUSE_EMULATE | TM_CAUSE_PERSISTENT))
+ return -EINVAL;
PPC_WARN_EMULATED(string, regs);
return emulate_string_inst(regs, instword);
}
@@ -1005,6 +1050,7 @@ int is_valid_bugaddr(unsigned long addr)
void __kprobes program_check_exception(struct pt_regs *regs)
{
+ enum ctx_state prev_state = exception_enter();
unsigned int reason = get_reason(regs);
extern int do_mathemu(struct pt_regs *regs);
@@ -1014,26 +1060,26 @@ void __kprobes program_check_exception(struct pt_regs *regs)
if (reason & REASON_FP) {
/* IEEE FP exception */
parse_fpe(regs);
- return;
+ goto bail;
}
if (reason & REASON_TRAP) {
/* Debugger is first in line to stop recursive faults in
* rcu_lock, notify_die, or atomic_notifier_call_chain */
if (debugger_bpt(regs))
- return;
+ goto bail;
/* trap exception */
if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP)
== NOTIFY_STOP)
- return;
+ goto bail;
if (!(regs->msr & MSR_PR) && /* not user-mode */
report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
regs->nip += 4;
- return;
+ goto bail;
}
_exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
- return;
+ goto bail;
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
if (reason & REASON_TM) {
@@ -1049,7 +1095,7 @@ void __kprobes program_check_exception(struct pt_regs *regs)
if (!user_mode(regs) &&
report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
regs->nip += 4;
- return;
+ goto bail;
}
/* If usermode caused this, it's done something illegal and
* gets a SIGILL slap on the wrist. We call it an illegal
@@ -1059,7 +1105,7 @@ void __kprobes program_check_exception(struct pt_regs *regs)
*/
if (user_mode(regs)) {
_exception(SIGILL, regs, ILL_ILLOPN, regs->nip);
- return;
+ goto bail;
} else {
printk(KERN_EMERG "Unexpected TM Bad Thing exception "
"at %lx (msr 0x%x)\n", regs->nip, reason);
@@ -1083,16 +1129,16 @@ void __kprobes program_check_exception(struct pt_regs *regs)
switch (do_mathemu(regs)) {
case 0:
emulate_single_step(regs);
- return;
+ goto bail;
case 1: {
int code = 0;
code = __parse_fpscr(current->thread.fpscr.val);
_exception(SIGFPE, regs, code, regs->nip);
- return;
+ goto bail;
}
case -EFAULT:
_exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
- return;
+ goto bail;
}
/* fall through on any other errors */
#endif /* CONFIG_MATH_EMULATION */
@@ -1103,10 +1149,10 @@ void __kprobes program_check_exception(struct pt_regs *regs)
case 0:
regs->nip += 4;
emulate_single_step(regs);
- return;
+ goto bail;
case -EFAULT:
_exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
- return;
+ goto bail;
}
}
@@ -1114,16 +1160,33 @@ void __kprobes program_check_exception(struct pt_regs *regs)
_exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
else
_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+
+bail:
+ exception_exit(prev_state);
+}
+
+/*
+ * This occurs when running in hypervisor mode on POWER6 or later
+ * and an illegal instruction is encountered.
+ */
+void __kprobes emulation_assist_interrupt(struct pt_regs *regs)
+{
+ regs->msr |= REASON_ILLEGAL;
+ program_check_exception(regs);
}
void alignment_exception(struct pt_regs *regs)
{
+ enum ctx_state prev_state = exception_enter();
int sig, code, fixed = 0;
/* We restore the interrupt state now */
if (!arch_irq_disabled_regs(regs))
local_irq_enable();
+ if (tm_abort_check(regs, TM_CAUSE_ALIGNMENT | TM_CAUSE_PERSISTENT))
+ goto bail;
+
/* we don't implement logging of alignment exceptions */
if (!(current->thread.align_ctl & PR_UNALIGN_SIGBUS))
fixed = fix_alignment(regs);
@@ -1131,7 +1194,7 @@ void alignment_exception(struct pt_regs *regs)
if (fixed == 1) {
regs->nip += 4; /* skip over emulated instruction */
emulate_single_step(regs);
- return;
+ goto bail;
}
/* Operand address was bad */
@@ -1146,6 +1209,9 @@ void alignment_exception(struct pt_regs *regs)
_exception(sig, regs, code, regs->dar);
else
bad_page_fault(regs, regs->dar, sig);
+
+bail:
+ exception_exit(prev_state);
}
void StackOverflow(struct pt_regs *regs)
@@ -1174,23 +1240,32 @@ void trace_syscall(struct pt_regs *regs)
void kernel_fp_unavailable_exception(struct pt_regs *regs)
{
+ enum ctx_state prev_state = exception_enter();
+
printk(KERN_EMERG "Unrecoverable FP Unavailable Exception "
"%lx at %lx\n", regs->trap, regs->nip);
die("Unrecoverable FP Unavailable Exception", regs, SIGABRT);
+
+ exception_exit(prev_state);
}
void altivec_unavailable_exception(struct pt_regs *regs)
{
+ enum ctx_state prev_state = exception_enter();
+
if (user_mode(regs)) {
/* A user program has executed an altivec instruction,
but this kernel doesn't support altivec. */
_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
- return;
+ goto bail;
}
printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception "
"%lx at %lx\n", regs->trap, regs->nip);
die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT);
+
+bail:
+ exception_exit(prev_state);
}
void vsx_unavailable_exception(struct pt_regs *regs)