arm64: dts: rockchip: add otg-port node of usb2-phy for rk3328 dwc2

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / mm / fault.c

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 0a726a548e7ad43fbbf1b2f570b4193d14e8961a..25547993a5ea66e188afdc5680238d1c15d492ff 100644 (file)
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -29,7 +29,9 @@
 #include <linux/sched.h>
 #include <linux/highmem.h>
 #include <linux/perf_event.h>
+#include <linux/preempt.h>
 
+#include <asm/bug.h>
 #include <asm/cpufeature.h>
 #include <asm/exception.h>
 #include <asm/debug-monitors.h>
@@ -41,6 +43,28 @@
 
 static const char *fault_name(unsigned int esr);
 
+#ifdef CONFIG_KPROBES
+static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr)
+{
+       int ret = 0;
+
+       /* kprobe_running() needs smp_processor_id() */
+       if (!user_mode(regs)) {
+               preempt_disable();
+               if (kprobe_running() && kprobe_fault_handler(regs, esr))
+                       ret = 1;
+               preempt_enable();
+       }
+
+       return ret;
+}
+#else
+static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr)
+{
+       return 0;
+}
+#endif
+
 /*
  * Dump out the page tables associated with 'addr' in mm 'mm'.
  */
@@ -131,6 +155,11 @@ int ptep_set_access_flags(struct vm_area_struct *vma,
 }
 #endif
 
+static bool is_el1_instruction_abort(unsigned int esr)
+{
+       return ESR_ELx_EC(esr) == ESR_ELx_EC_IABT_CUR;
+}
+
 /*
  * The kernel tried to access some page that wasn't present.
  */
@@ -139,8 +168,9 @@ static void __do_kernel_fault(struct mm_struct *mm, unsigned long addr,
 {
        /*
         * Are we prepared to handle this kernel fault?
+        * We are almost certainly not prepared to handle instruction faults.
         */
-       if (fixup_exception(regs))
+       if (!is_el1_instruction_abort(esr) && fixup_exception(regs))
                return;
 
        /*
@@ -240,12 +270,19 @@ out:
        return fault;
 }
 
-static inline bool is_permission_fault(unsigned int esr)
+static inline bool is_permission_fault(unsigned int esr, struct pt_regs *regs)
 {
        unsigned int ec       = ESR_ELx_EC(esr);
        unsigned int fsc_type = esr & ESR_ELx_FSC_TYPE;
 
-       return (ec == ESR_ELx_EC_DABT_CUR && fsc_type == ESR_ELx_FSC_PERM);
+       if (ec != ESR_ELx_EC_DABT_CUR && ec != ESR_ELx_EC_IABT_CUR)
+               return false;
+
+       if (system_uses_ttbr0_pan())
+               return fsc_type == ESR_ELx_FSC_FAULT &&
+                       (regs->pstate & PSR_PAN_BIT);
+       else
+               return fsc_type == ESR_ELx_FSC_PERM;
 }
 
 static bool is_el0_instruction_abort(unsigned int esr)
@@ -262,6 +299,9 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
        unsigned long vm_flags = VM_READ | VM_WRITE | VM_EXEC;
        unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
+       if (notify_page_fault(regs, esr))
+               return 0;
+
        tsk = current;
        mm  = tsk->mm;
 
@@ -286,10 +326,13 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
                mm_flags |= FAULT_FLAG_WRITE;
        }
 
-       if (is_permission_fault(esr) && (addr < USER_DS)) {
+       if (addr < USER_DS && is_permission_fault(esr, regs)) {
                if (get_fs() == KERNEL_DS)
                        die("Accessing user space memory with fs=KERNEL_DS", regs, esr);
 
+               if (is_el1_instruction_abort(esr))
+                       die("Attempting to execute userspace memory", regs, esr);
+
                if (!search_exception_tables(regs->pc))
                        die("Accessing user space memory outside uaccess.h routines", regs, esr);
        }
@@ -467,10 +510,10 @@ static const struct fault_info {
        { do_bad,               SIGBUS,  0,             "unknown 17"                    },
        { do_bad,               SIGBUS,  0,             "unknown 18"                    },
        { do_bad,               SIGBUS,  0,             "unknown 19"                    },
-       { do_bad,               SIGBUS,  0,             "synchronous abort (translation table walk)" },
-       { do_bad,               SIGBUS,  0,             "synchronous abort (translation table walk)" },
-       { do_bad,               SIGBUS,  0,             "synchronous abort (translation table walk)" },
-       { do_bad,               SIGBUS,  0,             "synchronous abort (translation table walk)" },
+       { do_bad,               SIGBUS,  0,             "synchronous external abort (translation table walk)" },
+       { do_bad,               SIGBUS,  0,             "synchronous external abort (translation table walk)" },
+       { do_bad,               SIGBUS,  0,             "synchronous external abort (translation table walk)" },
+       { do_bad,               SIGBUS,  0,             "synchronous external abort (translation table walk)" },
        { do_bad,               SIGBUS,  0,             "synchronous parity error"      },
        { do_bad,               SIGBUS,  0,             "unknown 25"                    },
        { do_bad,               SIGBUS,  0,             "unknown 26"                    },
@@ -616,11 +659,20 @@ asmlinkage int __exception do_debug_exception(unsigned long addr,
 
        return 0;
 }
+NOKPROBE_SYMBOL(do_debug_exception);
 
 #ifdef CONFIG_ARM64_PAN
-void cpu_enable_pan(void *__unused)
+int cpu_enable_pan(void *__unused)
 {
+       /*
+        * We modify PSTATE. This won't work from irq context as the PSTATE
+        * is discarded once we return from the exception.
+        */
+       WARN_ON_ONCE(in_interrupt());
+
        config_sctlr_el1(SCTLR_EL1_SPAN, 0);
+       asm(SET_PSTATE_PAN(1));
+       return 0;
 }
 #endif /* CONFIG_ARM64_PAN */
 
@@ -631,8 +683,9 @@ void cpu_enable_pan(void *__unused)
  * We need to enable the feature at runtime (instead of adding it to
  * PSR_MODE_EL1h) as the feature may not be implemented by the cpu.
  */
-void cpu_enable_uao(void *__unused)
+int cpu_enable_uao(void *__unused)
 {
        asm(SET_PSTATE_UAO(1));
+       return 0;
 }
 #endif /* CONFIG_ARM64_UAO */