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-rw-r--r--arch/powerpc/kernel/traps.c80
-rw-r--r--arch/powerpc/mm/fault.c41
-rw-r--r--arch/powerpc/mm/hash_utils_64.c36
3 files changed, 112 insertions, 45 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 83efa2f..a7a648f 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>
@@ -667,6 +668,7 @@ 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 +685,7 @@ 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 +695,23 @@ 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 +721,29 @@ 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 +753,20 @@ 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);
}
/*
@@ -1005,6 +1024,7 @@ 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 +1034,26 @@ 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 +1069,7 @@ 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 +1079,7 @@ 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 +1103,16 @@ 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 +1123,10 @@ 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;
}
}
@@ -1114,10 +1134,14 @@ 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);
}
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 */
@@ -1131,7 +1155,7 @@ 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 +1170,9 @@ 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 +1201,32 @@ 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)
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 229951f..8726779 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -32,6 +32,7 @@
#include <linux/perf_event.h>
#include <linux/magic.h>
#include <linux/ratelimit.h>
+#include <linux/context_tracking.h>
#include <asm/firmware.h>
#include <asm/page.h>
@@ -196,6 +197,7 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr, int fault)
int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
unsigned long error_code)
{
+ enum ctx_state prev_state = exception_enter();
struct vm_area_struct * vma;
struct mm_struct *mm = current->mm;
unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
@@ -204,6 +206,7 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
int trap = TRAP(regs);
int is_exec = trap == 0x400;
int fault;
+ int rc = 0;
#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
/*
@@ -230,28 +233,30 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
* look at it
*/
if (error_code & ICSWX_DSI_UCT) {
- int rc = acop_handle_fault(regs, address, error_code);
+ rc = acop_handle_fault(regs, address, error_code);
if (rc)
- return rc;
+ goto bail;
}
#endif /* CONFIG_PPC_ICSWX */
if (notify_page_fault(regs))
- return 0;
+ goto bail;
if (unlikely(debugger_fault_handler(regs)))
- return 0;
+ goto bail;
/* On a kernel SLB miss we can only check for a valid exception entry */
- if (!user_mode(regs) && (address >= TASK_SIZE))
- return SIGSEGV;
+ if (!user_mode(regs) && (address >= TASK_SIZE)) {
+ rc = SIGSEGV;
+ goto bail;
+ }
#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE) || \
defined(CONFIG_PPC_BOOK3S_64))
if (error_code & DSISR_DABRMATCH) {
/* breakpoint match */
do_break(regs, address, error_code);
- return 0;
+ goto bail;
}
#endif
@@ -260,8 +265,10 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
local_irq_enable();
if (in_atomic() || mm == NULL) {
- if (!user_mode(regs))
- return SIGSEGV;
+ if (!user_mode(regs)) {
+ rc = SIGSEGV;
+ goto bail;
+ }
/* in_atomic() in user mode is really bad,
as is current->mm == NULL. */
printk(KERN_EMERG "Page fault in user mode with "
@@ -417,9 +424,11 @@ good_area:
*/
fault = handle_mm_fault(mm, vma, address, flags);
if (unlikely(fault & (VM_FAULT_RETRY|VM_FAULT_ERROR))) {
- int rc = mm_fault_error(regs, address, fault);
+ rc = mm_fault_error(regs, address, fault);
if (rc >= MM_FAULT_RETURN)
- return rc;
+ goto bail;
+ else
+ rc = 0;
}
/*
@@ -454,7 +463,7 @@ good_area:
}
up_read(&mm->mmap_sem);
- return 0;
+ goto bail;
bad_area:
up_read(&mm->mmap_sem);
@@ -463,7 +472,7 @@ bad_area_nosemaphore:
/* User mode accesses cause a SIGSEGV */
if (user_mode(regs)) {
_exception(SIGSEGV, regs, code, address);
- return 0;
+ goto bail;
}
if (is_exec && (error_code & DSISR_PROTFAULT))
@@ -471,7 +480,11 @@ bad_area_nosemaphore:
" page (%lx) - exploit attempt? (uid: %d)\n",
address, from_kuid(&init_user_ns, current_uid()));
- return SIGSEGV;
+ rc = SIGSEGV;
+
+bail:
+ exception_exit(prev_state);
+ return rc;
}
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 88ac0ee..e303a6d 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -33,6 +33,7 @@
#include <linux/init.h>
#include <linux/signal.h>
#include <linux/memblock.h>
+#include <linux/context_tracking.h>
#include <asm/processor.h>
#include <asm/pgtable.h>
@@ -954,6 +955,7 @@ void hash_failure_debug(unsigned long ea, unsigned long access,
*/
int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
{
+ enum ctx_state prev_state = exception_enter();
pgd_t *pgdir;
unsigned long vsid;
struct mm_struct *mm;
@@ -973,7 +975,8 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
mm = current->mm;
if (! mm) {
DBG_LOW(" user region with no mm !\n");
- return 1;
+ rc = 1;
+ goto bail;
}
psize = get_slice_psize(mm, ea);
ssize = user_segment_size(ea);
@@ -992,19 +995,23 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
/* Not a valid range
* Send the problem up to do_page_fault
*/
- return 1;
+ rc = 1;
+ goto bail;
}
DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm, mm->pgd, vsid);
/* Bad address. */
if (!vsid) {
DBG_LOW("Bad address!\n");
- return 1;
+ rc = 1;
+ goto bail;
}
/* Get pgdir */
pgdir = mm->pgd;
- if (pgdir == NULL)
- return 1;
+ if (pgdir == NULL) {
+ rc = 1;
+ goto bail;
+ }
/* Check CPU locality */
tmp = cpumask_of(smp_processor_id());
@@ -1027,7 +1034,8 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
ptep = find_linux_pte_or_hugepte(pgdir, ea, &hugeshift);
if (ptep == NULL || !pte_present(*ptep)) {
DBG_LOW(" no PTE !\n");
- return 1;
+ rc = 1;
+ goto bail;
}
/* Add _PAGE_PRESENT to the required access perm */
@@ -1038,13 +1046,16 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
*/
if (access & ~pte_val(*ptep)) {
DBG_LOW(" no access !\n");
- return 1;
+ rc = 1;
+ goto bail;
}
#ifdef CONFIG_HUGETLB_PAGE
- if (hugeshift)
- return __hash_page_huge(ea, access, vsid, ptep, trap, local,
+ if (hugeshift) {
+ rc = __hash_page_huge(ea, access, vsid, ptep, trap, local,
ssize, hugeshift, psize);
+ goto bail;
+ }
#endif /* CONFIG_HUGETLB_PAGE */
#ifndef CONFIG_PPC_64K_PAGES
@@ -1124,6 +1135,9 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
pte_val(*(ptep + PTRS_PER_PTE)));
#endif
DBG_LOW(" -> rc=%d\n", rc);
+
+bail:
+ exception_exit(prev_state);
return rc;
}
EXPORT_SYMBOL_GPL(hash_page);
@@ -1259,6 +1273,8 @@ void flush_hash_range(unsigned long number, int local)
*/
void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc)
{
+ enum ctx_state prev_state = exception_enter();
+
if (user_mode(regs)) {
#ifdef CONFIG_PPC_SUBPAGE_PROT
if (rc == -2)
@@ -1268,6 +1284,8 @@ void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc)
_exception(SIGBUS, regs, BUS_ADRERR, address);
} else
bad_page_fault(regs, address, SIGBUS);
+
+ exception_exit(prev_state);
}
long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
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