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Diffstat (limited to 'arch/s390/mm/fault.c')
-rw-r--r--arch/s390/mm/fault.c443
1 files changed, 271 insertions, 172 deletions
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 0fc0a7e3c0e..3f3b35403d0 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -1,8 +1,6 @@
/*
- * arch/s390/mm/fault.c
- *
* S390 version
- * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Copyright IBM Corp. 1999
* Author(s): Hartmut Penner (hp@de.ibm.com)
* Ulrich Weigand (uweigand@de.ibm.com)
*
@@ -32,10 +30,10 @@
#include <linux/uaccess.h>
#include <linux/hugetlb.h>
#include <asm/asm-offsets.h>
-#include <asm/system.h>
#include <asm/pgtable.h>
#include <asm/irq.h>
#include <asm/mmu_context.h>
+#include <asm/facility.h>
#include "../kernel/entry.h"
#ifndef CONFIG_64BIT
@@ -51,14 +49,20 @@
#define VM_FAULT_BADCONTEXT 0x010000
#define VM_FAULT_BADMAP 0x020000
#define VM_FAULT_BADACCESS 0x040000
+#define VM_FAULT_SIGNAL 0x080000
+#define VM_FAULT_PFAULT 0x100000
-static unsigned long store_indication;
+static unsigned long store_indication __read_mostly;
-void fault_init(void)
+#ifdef CONFIG_64BIT
+static int __init fault_init(void)
{
- if (test_facility(2) && test_facility(75))
+ if (test_facility(75))
store_indication = 0xc00;
+ return 0;
}
+early_initcall(fault_init);
+#endif
static inline int notify_page_fault(struct pt_regs *regs)
{
@@ -102,30 +106,154 @@ void bust_spinlocks(int yes)
* Returns the address space associated with the fault.
* Returns 0 for kernel space and 1 for user space.
*/
-static inline int user_space_fault(unsigned long trans_exc_code)
+static inline int user_space_fault(struct pt_regs *regs)
{
+ unsigned long trans_exc_code;
+
/*
* The lowest two bits of the translation exception
* identification indicate which paging table was used.
*/
- trans_exc_code &= 3;
- if (trans_exc_code == 2)
- /* Access via secondary space, set_fs setting decides */
+ trans_exc_code = regs->int_parm_long & 3;
+ if (trans_exc_code == 3) /* home space -> kernel */
+ return 0;
+ if (user_mode(regs))
+ return 1;
+ if (trans_exc_code == 2) /* secondary space -> set_fs */
return current->thread.mm_segment.ar4;
- if (user_mode == HOME_SPACE_MODE)
- /* User space if the access has been done via home space. */
- return trans_exc_code == 3;
- /*
- * If the user space is not the home space the kernel runs in home
- * space. Access via secondary space has already been covered,
- * access via primary space or access register is from user space
- * and access via home space is from the kernel.
- */
- return trans_exc_code != 3;
+ if (current->flags & PF_VCPU)
+ return 1;
+ return 0;
}
-static inline void report_user_fault(struct pt_regs *regs, long int_code,
- int signr, unsigned long address)
+static int bad_address(void *p)
+{
+ unsigned long dummy;
+
+ return probe_kernel_address((unsigned long *)p, dummy);
+}
+
+#ifdef CONFIG_64BIT
+static void dump_pagetable(unsigned long asce, unsigned long address)
+{
+ unsigned long *table = __va(asce & PAGE_MASK);
+
+ pr_alert("AS:%016lx ", asce);
+ switch (asce & _ASCE_TYPE_MASK) {
+ case _ASCE_TYPE_REGION1:
+ table = table + ((address >> 53) & 0x7ff);
+ if (bad_address(table))
+ goto bad;
+ pr_cont("R1:%016lx ", *table);
+ if (*table & _REGION_ENTRY_INVALID)
+ goto out;
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ /* fallthrough */
+ case _ASCE_TYPE_REGION2:
+ table = table + ((address >> 42) & 0x7ff);
+ if (bad_address(table))
+ goto bad;
+ pr_cont("R2:%016lx ", *table);
+ if (*table & _REGION_ENTRY_INVALID)
+ goto out;
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ /* fallthrough */
+ case _ASCE_TYPE_REGION3:
+ table = table + ((address >> 31) & 0x7ff);
+ if (bad_address(table))
+ goto bad;
+ pr_cont("R3:%016lx ", *table);
+ if (*table & (_REGION_ENTRY_INVALID | _REGION3_ENTRY_LARGE))
+ goto out;
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ /* fallthrough */
+ case _ASCE_TYPE_SEGMENT:
+ table = table + ((address >> 20) & 0x7ff);
+ if (bad_address(table))
+ goto bad;
+ pr_cont(KERN_CONT "S:%016lx ", *table);
+ if (*table & (_SEGMENT_ENTRY_INVALID | _SEGMENT_ENTRY_LARGE))
+ goto out;
+ table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN);
+ }
+ table = table + ((address >> 12) & 0xff);
+ if (bad_address(table))
+ goto bad;
+ pr_cont("P:%016lx ", *table);
+out:
+ pr_cont("\n");
+ return;
+bad:
+ pr_cont("BAD\n");
+}
+
+#else /* CONFIG_64BIT */
+
+static void dump_pagetable(unsigned long asce, unsigned long address)
+{
+ unsigned long *table = __va(asce & PAGE_MASK);
+
+ pr_alert("AS:%08lx ", asce);
+ table = table + ((address >> 20) & 0x7ff);
+ if (bad_address(table))
+ goto bad;
+ pr_cont("S:%08lx ", *table);
+ if (*table & _SEGMENT_ENTRY_INVALID)
+ goto out;
+ table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN);
+ table = table + ((address >> 12) & 0xff);
+ if (bad_address(table))
+ goto bad;
+ pr_cont("P:%08lx ", *table);
+out:
+ pr_cont("\n");
+ return;
+bad:
+ pr_cont("BAD\n");
+}
+
+#endif /* CONFIG_64BIT */
+
+static void dump_fault_info(struct pt_regs *regs)
+{
+ unsigned long asce;
+
+ pr_alert("Fault in ");
+ switch (regs->int_parm_long & 3) {
+ case 3:
+ pr_cont("home space ");
+ break;
+ case 2:
+ pr_cont("secondary space ");
+ break;
+ case 1:
+ pr_cont("access register ");
+ break;
+ case 0:
+ pr_cont("primary space ");
+ break;
+ }
+ pr_cont("mode while using ");
+ if (!user_space_fault(regs)) {
+ asce = S390_lowcore.kernel_asce;
+ pr_cont("kernel ");
+ }
+#ifdef CONFIG_PGSTE
+ else if ((current->flags & PF_VCPU) && S390_lowcore.gmap) {
+ struct gmap *gmap = (struct gmap *)S390_lowcore.gmap;
+ asce = gmap->asce;
+ pr_cont("gmap ");
+ }
+#endif
+ else {
+ asce = S390_lowcore.user_asce;
+ pr_cont("user ");
+ }
+ pr_cont("ASCE.\n");
+ dump_pagetable(asce, regs->int_parm_long & __FAIL_ADDR_MASK);
+}
+
+static inline void report_user_fault(struct pt_regs *regs, long signr)
{
if ((task_pid_nr(current) > 1) && !show_unhandled_signals)
return;
@@ -133,10 +261,13 @@ static inline void report_user_fault(struct pt_regs *regs, long int_code,
return;
if (!printk_ratelimit())
return;
- printk("User process fault: interruption code 0x%lX ", int_code);
+ printk(KERN_ALERT "User process fault: interruption code 0x%X ",
+ regs->int_code);
print_vma_addr(KERN_CONT "in ", regs->psw.addr & PSW_ADDR_INSN);
- printk("\n");
- printk("failing address: %lX\n", address);
+ printk(KERN_CONT "\n");
+ printk(KERN_ALERT "failing address: %016lx TEID: %016lx\n",
+ regs->int_parm_long & __FAIL_ADDR_MASK, regs->int_parm_long);
+ dump_fault_info(regs);
show_regs(regs);
}
@@ -144,24 +275,18 @@ static inline void report_user_fault(struct pt_regs *regs, long int_code,
* Send SIGSEGV to task. This is an external routine
* to keep the stack usage of do_page_fault small.
*/
-static noinline void do_sigsegv(struct pt_regs *regs, long int_code,
- int si_code, unsigned long trans_exc_code)
+static noinline void do_sigsegv(struct pt_regs *regs, int si_code)
{
struct siginfo si;
- unsigned long address;
- address = trans_exc_code & __FAIL_ADDR_MASK;
- current->thread.prot_addr = address;
- current->thread.trap_no = int_code;
- report_user_fault(regs, int_code, SIGSEGV, address);
+ report_user_fault(regs, SIGSEGV);
si.si_signo = SIGSEGV;
si.si_code = si_code;
- si.si_addr = (void __user *) address;
+ si.si_addr = (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK);
force_sig_info(SIGSEGV, &si, current);
}
-static noinline void do_no_context(struct pt_regs *regs, long int_code,
- unsigned long trans_exc_code)
+static noinline void do_no_context(struct pt_regs *regs)
{
const struct exception_table_entry *fixup;
unsigned long address;
@@ -169,7 +294,7 @@ static noinline void do_no_context(struct pt_regs *regs, long int_code,
/* Are we prepared to handle this kernel fault? */
fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
if (fixup) {
- regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
+ regs->psw.addr = extable_fixup(fixup) | PSW_ADDR_AMODE;
return;
}
@@ -177,55 +302,50 @@ static noinline void do_no_context(struct pt_regs *regs, long int_code,
* Oops. The kernel tried to access some bad page. We'll have to
* terminate things with extreme prejudice.
*/
- address = trans_exc_code & __FAIL_ADDR_MASK;
- if (!user_space_fault(trans_exc_code))
+ address = regs->int_parm_long & __FAIL_ADDR_MASK;
+ if (!user_space_fault(regs))
printk(KERN_ALERT "Unable to handle kernel pointer dereference"
- " at virtual kernel address %p\n", (void *)address);
+ " in virtual kernel address space\n");
else
printk(KERN_ALERT "Unable to handle kernel paging request"
- " at virtual user address %p\n", (void *)address);
-
- die("Oops", regs, int_code);
+ " in virtual user address space\n");
+ printk(KERN_ALERT "failing address: %016lx TEID: %016lx\n",
+ regs->int_parm_long & __FAIL_ADDR_MASK, regs->int_parm_long);
+ dump_fault_info(regs);
+ die(regs, "Oops");
do_exit(SIGKILL);
}
-static noinline void do_low_address(struct pt_regs *regs, long int_code,
- unsigned long trans_exc_code)
+static noinline void do_low_address(struct pt_regs *regs)
{
/* Low-address protection hit in kernel mode means
NULL pointer write access in kernel mode. */
if (regs->psw.mask & PSW_MASK_PSTATE) {
/* Low-address protection hit in user mode 'cannot happen'. */
- die ("Low-address protection", regs, int_code);
+ die (regs, "Low-address protection");
do_exit(SIGKILL);
}
- do_no_context(regs, int_code, trans_exc_code);
+ do_no_context(regs);
}
-static noinline void do_sigbus(struct pt_regs *regs, long int_code,
- unsigned long trans_exc_code)
+static noinline void do_sigbus(struct pt_regs *regs)
{
struct task_struct *tsk = current;
- unsigned long address;
struct siginfo si;
/*
* Send a sigbus, regardless of whether we were in kernel
* or user mode.
*/
- address = trans_exc_code & __FAIL_ADDR_MASK;
- tsk->thread.prot_addr = address;
- tsk->thread.trap_no = int_code;
si.si_signo = SIGBUS;
si.si_errno = 0;
si.si_code = BUS_ADRERR;
- si.si_addr = (void __user *) address;
+ si.si_addr = (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK);
force_sig_info(SIGBUS, &si, tsk);
}
-static noinline void do_fault_error(struct pt_regs *regs, long int_code,
- unsigned long trans_exc_code, int fault)
+static noinline void do_fault_error(struct pt_regs *regs, int fault)
{
int si_code;
@@ -233,28 +353,33 @@ static noinline void do_fault_error(struct pt_regs *regs, long int_code,
case VM_FAULT_BADACCESS:
case VM_FAULT_BADMAP:
/* Bad memory access. Check if it is kernel or user space. */
- if (regs->psw.mask & PSW_MASK_PSTATE) {
+ if (user_mode(regs)) {
/* User mode accesses just cause a SIGSEGV */
si_code = (fault == VM_FAULT_BADMAP) ?
SEGV_MAPERR : SEGV_ACCERR;
- do_sigsegv(regs, int_code, si_code, trans_exc_code);
+ do_sigsegv(regs, si_code);
return;
}
case VM_FAULT_BADCONTEXT:
- do_no_context(regs, int_code, trans_exc_code);
+ case VM_FAULT_PFAULT:
+ do_no_context(regs);
+ break;
+ case VM_FAULT_SIGNAL:
+ if (!user_mode(regs))
+ do_no_context(regs);
break;
default: /* fault & VM_FAULT_ERROR */
if (fault & VM_FAULT_OOM) {
- if (!(regs->psw.mask & PSW_MASK_PSTATE))
- do_no_context(regs, int_code, trans_exc_code);
+ if (!user_mode(regs))
+ do_no_context(regs);
else
pagefault_out_of_memory();
} else if (fault & VM_FAULT_SIGBUS) {
/* Kernel mode? Handle exceptions or die */
- if (!(regs->psw.mask & PSW_MASK_PSTATE))
- do_no_context(regs, int_code, trans_exc_code);
+ if (!user_mode(regs))
+ do_no_context(regs);
else
- do_sigbus(regs, int_code, trans_exc_code);
+ do_sigbus(regs);
} else
BUG();
break;
@@ -272,21 +397,31 @@ static noinline void do_fault_error(struct pt_regs *regs, long int_code,
* 11 Page translation -> Not present (nullification)
* 3b Region third trans. -> Not present (nullification)
*/
-static inline int do_exception(struct pt_regs *regs, int access,
- unsigned long trans_exc_code)
+static inline int do_exception(struct pt_regs *regs, int access)
{
+#ifdef CONFIG_PGSTE
+ struct gmap *gmap;
+#endif
struct task_struct *tsk;
struct mm_struct *mm;
struct vm_area_struct *vma;
+ unsigned long trans_exc_code;
unsigned long address;
unsigned int flags;
int fault;
+ tsk = current;
+ /*
+ * The instruction that caused the program check has
+ * been nullified. Don't signal single step via SIGTRAP.
+ */
+ clear_pt_regs_flag(regs, PIF_PER_TRAP);
+
if (notify_page_fault(regs))
return 0;
- tsk = current;
mm = tsk->mm;
+ trans_exc_code = regs->int_parm_long;
/*
* Verify that the fault happened in user space, that
@@ -294,20 +429,23 @@ static inline int do_exception(struct pt_regs *regs, int access,
* user context.
*/
fault = VM_FAULT_BADCONTEXT;
- if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm))
+ if (unlikely(!user_space_fault(regs) || in_atomic() || !mm))
goto out;
address = trans_exc_code & __FAIL_ADDR_MASK;
perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
- flags = FAULT_FLAG_ALLOW_RETRY;
+ flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ if (user_mode(regs))
+ flags |= FAULT_FLAG_USER;
if (access == VM_WRITE || (trans_exc_code & store_indication) == 0x400)
flags |= FAULT_FLAG_WRITE;
down_read(&mm->mmap_sem);
#ifdef CONFIG_PGSTE
- if (test_tsk_thread_flag(current, TIF_SIE) && S390_lowcore.gmap) {
- address = __gmap_fault(address,
- (struct gmap *) S390_lowcore.gmap);
+ gmap = (struct gmap *)
+ ((current->flags & PF_VCPU) ? S390_lowcore.gmap : 0);
+ if (gmap) {
+ address = __gmap_fault(address, gmap);
if (address == -EFAULT) {
fault = VM_FAULT_BADMAP;
goto out_up;
@@ -316,6 +454,8 @@ static inline int do_exception(struct pt_regs *regs, int access,
fault = VM_FAULT_OOM;
goto out_up;
}
+ if (gmap->pfault_enabled)
+ flags |= FAULT_FLAG_RETRY_NOWAIT;
}
#endif
@@ -348,6 +488,11 @@ retry:
* the fault.
*/
fault = handle_mm_fault(mm, vma, address, flags);
+ /* No reason to continue if interrupted by SIGKILL. */
+ if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) {
+ fault = VM_FAULT_SIGNAL;
+ goto out;
+ }
if (unlikely(fault & VM_FAULT_ERROR))
goto out_up;
@@ -367,18 +512,24 @@ retry:
regs, address);
}
if (fault & VM_FAULT_RETRY) {
+#ifdef CONFIG_PGSTE
+ if (gmap && (flags & FAULT_FLAG_RETRY_NOWAIT)) {
+ /* FAULT_FLAG_RETRY_NOWAIT has been set,
+ * mmap_sem has not been released */
+ current->thread.gmap_pfault = 1;
+ fault = VM_FAULT_PFAULT;
+ goto out_up;
+ }
+#endif
/* Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk
* of starvation. */
- flags &= ~FAULT_FLAG_ALLOW_RETRY;
+ flags &= ~(FAULT_FLAG_ALLOW_RETRY |
+ FAULT_FLAG_RETRY_NOWAIT);
+ flags |= FAULT_FLAG_TRIED;
down_read(&mm->mmap_sem);
goto retry;
}
}
- /*
- * The instruction that caused the program check will
- * be repeated. Don't signal single step via SIGTRAP.
- */
- clear_tsk_thread_flag(tsk, TIF_PER_TRAP);
fault = 0;
out_up:
up_read(&mm->mmap_sem);
@@ -386,89 +537,41 @@ out:
return fault;
}
-void __kprobes do_protection_exception(struct pt_regs *regs, long pgm_int_code,
- unsigned long trans_exc_code)
+void __kprobes do_protection_exception(struct pt_regs *regs)
{
+ unsigned long trans_exc_code;
int fault;
- /* Protection exception is suppressing, decrement psw address. */
- regs->psw.addr = __rewind_psw(regs->psw, pgm_int_code >> 16);
+ trans_exc_code = regs->int_parm_long;
+ /*
+ * Protection exceptions are suppressing, decrement psw address.
+ * The exception to this rule are aborted transactions, for these
+ * the PSW already points to the correct location.
+ */
+ if (!(regs->int_code & 0x200))
+ regs->psw.addr = __rewind_psw(regs->psw, regs->int_code >> 16);
/*
* Check for low-address protection. This needs to be treated
* as a special case because the translation exception code
* field is not guaranteed to contain valid data in this case.
*/
if (unlikely(!(trans_exc_code & 4))) {
- do_low_address(regs, pgm_int_code, trans_exc_code);
+ do_low_address(regs);
return;
}
- fault = do_exception(regs, VM_WRITE, trans_exc_code);
+ fault = do_exception(regs, VM_WRITE);
if (unlikely(fault))
- do_fault_error(regs, 4, trans_exc_code, fault);
+ do_fault_error(regs, fault);
}
-void __kprobes do_dat_exception(struct pt_regs *regs, long pgm_int_code,
- unsigned long trans_exc_code)
+void __kprobes do_dat_exception(struct pt_regs *regs)
{
int access, fault;
access = VM_READ | VM_EXEC | VM_WRITE;
- fault = do_exception(regs, access, trans_exc_code);
+ fault = do_exception(regs, access);
if (unlikely(fault))
- do_fault_error(regs, pgm_int_code & 255, trans_exc_code, fault);
-}
-
-#ifdef CONFIG_64BIT
-void __kprobes do_asce_exception(struct pt_regs *regs, long pgm_int_code,
- unsigned long trans_exc_code)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
-
- if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm))
- goto no_context;
-
- down_read(&mm->mmap_sem);
- vma = find_vma(mm, trans_exc_code & __FAIL_ADDR_MASK);
- up_read(&mm->mmap_sem);
-
- if (vma) {
- update_mm(mm, current);
- return;
- }
-
- /* User mode accesses just cause a SIGSEGV */
- if (regs->psw.mask & PSW_MASK_PSTATE) {
- do_sigsegv(regs, pgm_int_code, SEGV_MAPERR, trans_exc_code);
- return;
- }
-
-no_context:
- do_no_context(regs, pgm_int_code, trans_exc_code);
-}
-#endif
-
-int __handle_fault(unsigned long uaddr, unsigned long pgm_int_code, int write)
-{
- struct pt_regs regs;
- int access, fault;
-
- /* Emulate a uaccess fault from kernel mode. */
- regs.psw.mask = psw_kernel_bits | PSW_MASK_DAT | PSW_MASK_MCHECK;
- if (!irqs_disabled())
- regs.psw.mask |= PSW_MASK_IO | PSW_MASK_EXT;
- regs.psw.addr = (unsigned long) __builtin_return_address(0);
- regs.psw.addr |= PSW_ADDR_AMODE;
- uaddr &= PAGE_MASK;
- access = write ? VM_WRITE : VM_READ;
- fault = do_exception(&regs, access, uaddr | 2);
- /*
- * Since the fault happened in kernel mode while performing a uaccess
- * all we need to do now is emulating a fixup in case "fault" is not
- * zero.
- * For the calling uaccess functions this results always in -EFAULT.
- */
- return fault ? -EFAULT : 0;
+ do_fault_error(regs, fault);
}
#ifdef CONFIG_PFAULT
@@ -509,7 +612,7 @@ int pfault_init(void)
.reserved = __PF_RES_FIELD };
int rc;
- if (!MACHINE_IS_VM || pfault_disable)
+ if (pfault_disable)
return -1;
asm volatile(
" diag %1,%0,0x258\n"
@@ -530,7 +633,7 @@ void pfault_fini(void)
.refversn = 2,
};
- if (!MACHINE_IS_VM || pfault_disable)
+ if (pfault_disable)
return;
asm volatile(
" diag %0,0,0x258\n"
@@ -542,7 +645,7 @@ void pfault_fini(void)
static DEFINE_SPINLOCK(pfault_lock);
static LIST_HEAD(pfault_list);
-static void pfault_interrupt(unsigned int ext_int_code,
+static void pfault_interrupt(struct ext_code ext_code,
unsigned int param32, unsigned long param64)
{
struct task_struct *tsk;
@@ -555,23 +658,19 @@ static void pfault_interrupt(unsigned int ext_int_code,
* in the 'cpu address' field associated with the
* external interrupt.
*/
- subcode = ext_int_code >> 16;
+ subcode = ext_code.subcode;
if ((subcode & 0xff00) != __SUBCODE_MASK)
return;
- kstat_cpu(smp_processor_id()).irqs[EXTINT_PFL]++;
- if (subcode & 0x0080) {
- /* Get the token (= pid of the affected task). */
- pid = sizeof(void *) == 4 ? param32 : param64;
- rcu_read_lock();
- tsk = find_task_by_pid_ns(pid, &init_pid_ns);
- if (tsk)
- get_task_struct(tsk);
- rcu_read_unlock();
- if (!tsk)
- return;
- } else {
- tsk = current;
- }
+ inc_irq_stat(IRQEXT_PFL);
+ /* Get the token (= pid of the affected task). */
+ pid = sizeof(void *) == 4 ? param32 : param64;
+ rcu_read_lock();
+ tsk = find_task_by_pid_ns(pid, &init_pid_ns);
+ if (tsk)
+ get_task_struct(tsk);
+ rcu_read_unlock();
+ if (!tsk)
+ return;
spin_lock(&pfault_lock);
if (subcode & 0x0080) {
/* signal bit is set -> a page has been swapped in by VM */
@@ -596,12 +695,13 @@ static void pfault_interrupt(unsigned int ext_int_code,
if (tsk->state == TASK_RUNNING)
tsk->thread.pfault_wait = -1;
}
- put_task_struct(tsk);
} else {
/* signal bit not set -> a real page is missing. */
+ if (WARN_ON_ONCE(tsk != current))
+ goto out;
if (tsk->thread.pfault_wait == 1) {
/* Already on the list with a reference: put to sleep */
- set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+ __set_task_state(tsk, TASK_UNINTERRUPTIBLE);
set_tsk_need_resched(tsk);
} else if (tsk->thread.pfault_wait == -1) {
/* Completion interrupt was faster than the initial
@@ -617,22 +717,23 @@ static void pfault_interrupt(unsigned int ext_int_code,
get_task_struct(tsk);
tsk->thread.pfault_wait = 1;
list_add(&tsk->thread.list, &pfault_list);
- set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+ __set_task_state(tsk, TASK_UNINTERRUPTIBLE);
set_tsk_need_resched(tsk);
}
}
+out:
spin_unlock(&pfault_lock);
+ put_task_struct(tsk);
}
-static int __cpuinit pfault_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
+static int pfault_cpu_notify(struct notifier_block *self, unsigned long action,
+ void *hcpu)
{
struct thread_struct *thread, *next;
struct task_struct *tsk;
- switch (action) {
+ switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DEAD:
- case CPU_DEAD_FROZEN:
spin_lock_irq(&pfault_lock);
list_for_each_entry_safe(thread, next, &pfault_list, list) {
thread->pfault_wait = 0;
@@ -653,20 +754,18 @@ static int __init pfault_irq_init(void)
{
int rc;
- if (!MACHINE_IS_VM)
- return 0;
- rc = register_external_interrupt(0x2603, pfault_interrupt);
+ rc = register_external_irq(EXT_IRQ_CP_SERVICE, pfault_interrupt);
if (rc)
goto out_extint;
rc = pfault_init() == 0 ? 0 : -EOPNOTSUPP;
if (rc)
goto out_pfault;
- service_subclass_irq_register();
+ irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
hotcpu_notifier(pfault_cpu_notify, 0);
return 0;
out_pfault:
- unregister_external_interrupt(0x2603, pfault_interrupt);
+ unregister_external_irq(EXT_IRQ_CP_SERVICE, pfault_interrupt);
out_extint:
pfault_disable = 1;
return rc;
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-14 05:38:49 +0000