Merge tag 'v4.4.46' into linux-linaro-lsk-v4.4

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

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index bdc293f6adc43b347c85272d4868a3975f67fe72..a036ff290d69d4687477bfd5f4c42f385474bac2 100644 (file)
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -146,9 +146,18 @@ static void dump_instr(const char *lvl, struct pt_regs *regs)
 static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
 {
        struct stackframe frame;
-       unsigned long irq_stack_ptr = IRQ_STACK_PTR(smp_processor_id());
+       unsigned long irq_stack_ptr;
        int skip;
 
+       /*
+        * Switching between stacks is valid when tracing current and in
+        * non-preemptible context.
+        */
+       if (tsk == current && !preemptible())
+               irq_stack_ptr = IRQ_STACK_PTR(smp_processor_id());
+       else
+               irq_stack_ptr = 0;
+
        pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
 
        if (!tsk)
@@ -171,7 +180,7 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
 #endif
 
        skip = !!regs;
-       pr_emerg("Call trace:\n");
+       printk("Call trace:\n");
        while (1) {
                unsigned long where = frame.pc;
                unsigned long stack;
@@ -460,16 +469,33 @@ const char *esr_get_class_string(u32 esr)
 }
 
 /*
- * bad_mode handles the impossible case in the exception vector.
+ * bad_mode handles the impossible case in the exception vector. This is always
+ * fatal.
  */
 asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
 {
-       siginfo_t info;
-       void __user *pc = (void __user *)instruction_pointer(regs);
        console_verbose();
 
        pr_crit("Bad mode in %s handler detected, code 0x%08x -- %s\n",
                handler[reason], esr, esr_get_class_string(esr));
+
+       die("Oops - bad mode", regs, 0);
+       local_irq_disable();
+       panic("bad mode");
+}
+
+/*
+ * bad_el0_sync handles unexpected, but potentially recoverable synchronous
+ * exceptions taken from EL0. Unlike bad_mode, this returns.
+ */
+asmlinkage void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr)
+{
+       siginfo_t info;
+       void __user *pc = (void __user *)instruction_pointer(regs);
+       console_verbose();
+
+       pr_crit("Bad EL0 synchronous exception detected on CPU%d, code 0x%08x -- %s\n",
+               smp_processor_id(), esr, esr_get_class_string(esr));
        __show_regs(regs);
 
        info.si_signo = SIGILL;
@@ -477,27 +503,30 @@ asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
        info.si_code  = ILL_ILLOPC;
        info.si_addr  = pc;
 
-       arm64_notify_die("Oops - bad mode", regs, &info, 0);
+       current->thread.fault_address = 0;
+       current->thread.fault_code = 0;
+
+       force_sig_info(info.si_signo, &info, current);
 }
 
 void __pte_error(const char *file, int line, unsigned long val)
 {
-       pr_crit("%s:%d: bad pte %016lx.\n", file, line, val);
+       pr_err("%s:%d: bad pte %016lx.\n", file, line, val);
 }
 
 void __pmd_error(const char *file, int line, unsigned long val)
 {
-       pr_crit("%s:%d: bad pmd %016lx.\n", file, line, val);
+       pr_err("%s:%d: bad pmd %016lx.\n", file, line, val);
 }
 
 void __pud_error(const char *file, int line, unsigned long val)
 {
-       pr_crit("%s:%d: bad pud %016lx.\n", file, line, val);
+       pr_err("%s:%d: bad pud %016lx.\n", file, line, val);
 }
 
 void __pgd_error(const char *file, int line, unsigned long val)
 {
-       pr_crit("%s:%d: bad pgd %016lx.\n", file, line, val);
+       pr_err("%s:%d: bad pgd %016lx.\n", file, line, val);
 }
 
 /* GENERIC_BUG traps */