#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/kdebug.h>
+#include <asm/s390_ext.h>
#ifndef CONFIG_64BIT
#define __FAIL_ADDR_MASK 0x7ffff000
extern void die(const char *,struct pt_regs *,long);
#ifdef CONFIG_KPROBES
-ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
+static ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
int register_page_fault_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_register(¬ify_page_fault_chain, nb);
}
#endif
-extern spinlock_t timerlist_lock;
/*
* Unlock any spinlocks which will prevent us from getting the
- * message out (timerlist_lock is acquired through the
- * console unblank code)
+ * message out.
*/
void bust_spinlocks(int yes)
{
/*
* Check which address space the address belongs to.
- * Returns 1 for user space and 0 for kernel space.
+ * May return 1 or 2 for user space and 0 for kernel space.
+ * Returns 2 for user space in primary addressing mode with
+ * CONFIG_S390_EXEC_PROTECT on and kernel parameter noexec=on.
*/
static inline int check_user_space(struct pt_regs *regs, int error_code)
{
return __check_access_register(regs, error_code);
if (descriptor == 2)
return current->thread.mm_segment.ar4;
- return descriptor != 0;
+ return ((descriptor != 0) ^ (switch_amode)) << s390_noexec;
}
/*
force_sig_info(SIGSEGV, &si, current);
}
+#ifdef CONFIG_S390_EXEC_PROTECT
+extern long sys_sigreturn(struct pt_regs *regs);
+extern long sys_rt_sigreturn(struct pt_regs *regs);
+extern long sys32_sigreturn(struct pt_regs *regs);
+extern long sys32_rt_sigreturn(struct pt_regs *regs);
+
+static inline void do_sigreturn(struct mm_struct *mm, struct pt_regs *regs,
+ int rt)
+{
+ up_read(&mm->mmap_sem);
+ clear_tsk_thread_flag(current, TIF_SINGLE_STEP);
+#ifdef CONFIG_COMPAT
+ if (test_tsk_thread_flag(current, TIF_31BIT)) {
+ if (rt)
+ sys32_rt_sigreturn(regs);
+ else
+ sys32_sigreturn(regs);
+ return;
+ }
+#endif /* CONFIG_COMPAT */
+ if (rt)
+ sys_rt_sigreturn(regs);
+ else
+ sys_sigreturn(regs);
+ return;
+}
+
+static int signal_return(struct mm_struct *mm, struct pt_regs *regs,
+ unsigned long address, unsigned long error_code)
+{
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+ u16 *instruction;
+ unsigned long pfn, uaddr = regs->psw.addr;
+
+ spin_lock(&mm->page_table_lock);
+ pgd = pgd_offset(mm, uaddr);
+ if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
+ goto out_fault;
+ pmd = pmd_offset(pgd, uaddr);
+ if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
+ goto out_fault;
+ pte = pte_offset_map(pmd_offset(pgd_offset(mm, uaddr), uaddr), uaddr);
+ if (!pte || !pte_present(*pte))
+ goto out_fault;
+ pfn = pte_pfn(*pte);
+ if (!pfn_valid(pfn))
+ goto out_fault;
+ spin_unlock(&mm->page_table_lock);
+
+ instruction = (u16 *) ((pfn << PAGE_SHIFT) + (uaddr & (PAGE_SIZE-1)));
+ if (*instruction == 0x0a77)
+ do_sigreturn(mm, regs, 0);
+ else if (*instruction == 0x0aad)
+ do_sigreturn(mm, regs, 1);
+ else {
+ printk("- XXX - do_exception: task = %s, primary, NO EXEC "
+ "-> SIGSEGV\n", current->comm);
+ up_read(&mm->mmap_sem);
+ current->thread.prot_addr = address;
+ current->thread.trap_no = error_code;
+ do_sigsegv(regs, error_code, SEGV_MAPERR, address);
+ }
+ return 0;
+out_fault:
+ spin_unlock(&mm->page_table_lock);
+ return -EFAULT;
+}
+#endif /* CONFIG_S390_EXEC_PROTECT */
+
/*
* This routine handles page faults. It determines the address,
* and the problem, and then passes it off to one of the appropriate
vma = find_vma(mm, address);
if (!vma)
goto bad_area;
+
+#ifdef CONFIG_S390_EXEC_PROTECT
+ if (unlikely((user_address == 2) && !(vma->vm_flags & VM_EXEC)))
+ if (!signal_return(mm, regs, address, error_code))
+ /*
+ * signal_return() has done an up_read(&mm->mmap_sem)
+ * if it returns 0.
+ */
+ return;
+#endif
+
if (vma->vm_start <= address)
goto good_area;
if (!(vma->vm_flags & VM_GROWSDOWN))
/*
* 'pfault' pseudo page faults routines.
*/
+static ext_int_info_t ext_int_pfault;
static int pfault_disable = 0;
static int __init nopfault(char *str)
__PF_RES_FIELD };
int rc;
- if (pfault_disable)
+ if (!MACHINE_IS_VM || pfault_disable)
return -1;
asm volatile(
" diag %1,%0,0x258\n"
pfault_refbk_t refbk =
{ 0x258, 1, 5, 2, 0ULL, 0ULL, 0ULL, 0ULL };
- if (pfault_disable)
+ if (!MACHINE_IS_VM || pfault_disable)
return;
__ctl_clear_bit(0,9);
asm volatile(
: : "a" (&refbk), "m" (refbk) : "cc");
}
-asmlinkage void
-pfault_interrupt(__u16 error_code)
+static void pfault_interrupt(__u16 error_code)
{
struct task_struct *tsk;
__u16 subcode;
set_tsk_need_resched(tsk);
}
}
-#endif
+void __init pfault_irq_init(void)
+{
+ if (!MACHINE_IS_VM)
+ return;
+
+ /*
+ * Try to get pfault pseudo page faults going.
+ */
+ if (register_early_external_interrupt(0x2603, pfault_interrupt,
+ &ext_int_pfault) != 0)
+ panic("Couldn't request external interrupt 0x2603");
+
+ if (pfault_init() == 0)
+ return;
+
+ /* Tough luck, no pfault. */
+ pfault_disable = 1;
+ unregister_early_external_interrupt(0x2603, pfault_interrupt,
+ &ext_int_pfault);
+}
+#endif