[PATCH] ARM: Don't try to send a signal to pid0

If we receive an unrecognised abort during boot, don't try to
send a signal to pid0, but instead report the current state.
This leads to less confusing debug reports.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

3 files changed, 45 insertions, 46 deletions

diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 2fb0a4cfb37a..df2cb06ce424 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -230,16 +230,8 @@ NORET_TYPE void die(const char *str, struct pt_regs *regs, int err)
         do_exit(SIGSEGV);
 }
 
-void die_if_kernel(const char *str, struct pt_regs *regs, int err)
-{
-        if (user_mode(regs))
-                return;
-
-        die(str, regs, err);
-}
-
-static void notify_die(const char *str, struct pt_regs *regs, siginfo_t *info,
-                       unsigned long err, unsigned long trap)
+void notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
+                unsigned long err, unsigned long trap)
 {
         if (user_mode(regs)) {
                 current->thread.error_code = err;
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index e25b4fd8412c..65bfe84b6d67 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -372,49 +372,50 @@ do_bad(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 static struct fsr_info {
         int     (*fn)(unsigned long addr, unsigned int fsr, struct pt_regs *regs);
         int     sig;
+        int     code;
         const char *name;
 } fsr_info[] = {
         /*
          * The following are the standard ARMv3 and ARMv4 aborts.  ARMv5
          * defines these to be "precise" aborts.
          */
-        { do_bad,               SIGSEGV, "vector exception"                },
-        { do_bad,               SIGILL,  "alignment exception"             },
-        { do_bad,               SIGKILL, "terminal exception"              },
-        { do_bad,               SIGILL,  "alignment exception"             },
-        { do_bad,               SIGBUS,  "external abort on linefetch"     },
-        { do_translation_fault, SIGSEGV, "section translation fault"       },
-        { do_bad,               SIGBUS,  "external abort on linefetch"     },
-        { do_page_fault,        SIGSEGV, "page translation fault"          },
-        { do_bad,               SIGBUS,  "external abort on non-linefetch" },
-        { do_bad,               SIGSEGV, "section domain fault"            },
-        { do_bad,               SIGBUS,  "external abort on non-linefetch" },
-        { do_bad,               SIGSEGV, "page domain fault"               },
-        { do_bad,               SIGBUS,  "external abort on translation"   },
-        { do_sect_fault,        SIGSEGV, "section permission fault"        },
-        { do_bad,               SIGBUS,  "external abort on translation"   },
-        { do_page_fault,        SIGSEGV, "page permission fault"           },
+        { do_bad,               SIGSEGV, 0,             "vector exception"                 },
+        { do_bad,               SIGILL,  BUS_ADRALN,    "alignment exception"              },
+        { do_bad,               SIGKILL, 0,             "terminal exception"               },
+        { do_bad,               SIGILL,  BUS_ADRALN,    "alignment exception"              },
+        { do_bad,               SIGBUS,  0,             "external abort on linefetch"      },
+        { do_translation_fault, SIGSEGV, SEGV_MAPERR,   "section translation fault"        },
+        { do_bad,               SIGBUS,  0,             "external abort on linefetch"      },
+        { do_page_fault,        SIGSEGV, SEGV_MAPERR,   "page translation fault"           },
+        { do_bad,               SIGBUS,  0,             "external abort on non-linefetch"  },
+        { do_bad,               SIGSEGV, SEGV_ACCERR,   "section domain fault"             },
+        { do_bad,               SIGBUS,  0,             "external abort on non-linefetch"  },
+        { do_bad,               SIGSEGV, SEGV_ACCERR,   "page domain fault"                },
+        { do_bad,               SIGBUS,  0,             "external abort on translation"    },
+        { do_sect_fault,        SIGSEGV, SEGV_ACCERR,   "section permission fault"         },
+        { do_bad,               SIGBUS,  0,             "external abort on translation"    },
+        { do_page_fault,        SIGSEGV, SEGV_ACCERR,   "page permission fault"            },
         /*
          * The following are "imprecise" aborts, which are signalled by bit
          * 10 of the FSR, and may not be recoverable.  These are only
          * supported if the CPU abort handler supports bit 10.
          */
-        { do_bad,               SIGBUS,  "unknown 16"                      },
-        { do_bad,               SIGBUS,  "unknown 17"                      },
-        { do_bad,               SIGBUS,  "unknown 18"                      },
-        { do_bad,               SIGBUS,  "unknown 19"                      },
-        { do_bad,               SIGBUS,  "lock abort"                      }, /* xscale */
-        { do_bad,               SIGBUS,  "unknown 21"                      },
-        { do_bad,               SIGBUS,  "imprecise external abort"        }, /* xscale */
-        { do_bad,               SIGBUS,  "unknown 23"                      },
-        { do_bad,               SIGBUS,  "dcache parity error"             }, /* xscale */
-        { do_bad,               SIGBUS,  "unknown 25"                      },
-        { do_bad,               SIGBUS,  "unknown 26"                      },
-        { do_bad,               SIGBUS,  "unknown 27"                      },
-        { do_bad,               SIGBUS,  "unknown 28"                      },
-        { do_bad,               SIGBUS,  "unknown 29"                      },
-        { do_bad,               SIGBUS,  "unknown 30"                      },
-        { do_bad,               SIGBUS,  "unknown 31"                      }
+        { do_bad,               SIGBUS,  0,             "unknown 16"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 17"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 18"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 19"                       },
+        { do_bad,               SIGBUS,  0,             "lock abort"                       }, /* xscale */
+        { do_bad,               SIGBUS,  0,             "unknown 21"                       },
+        { do_bad,               SIGBUS,  BUS_OBJERR,    "imprecise external abort"         }, /* xscale */
+        { do_bad,               SIGBUS,  0,             "unknown 23"                       },
+        { do_bad,               SIGBUS,  0,             "dcache parity error"              }, /* xscale */
+        { do_bad,               SIGBUS,  0,             "unknown 25"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 26"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 27"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 28"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 29"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 30"                       },
+        { do_bad,               SIGBUS,  0,             "unknown 31"                       }
 };
 
 void __init
@@ -435,15 +436,19 @@ asmlinkage void
 do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 {
         const struct fsr_info *inf = fsr_info + (fsr & 15) + ((fsr & (1 << 10)) >> 6);
+        struct siginfo info;
 
         if (!inf->fn(addr, fsr, regs))
                 return;
 
         printk(KERN_ALERT "Unhandled fault: %s (0x%03x) at 0x%08lx\n",
                 inf->name, fsr, addr);
-        force_sig(inf->sig, current);
-        show_pte(current->mm, addr);
-        die_if_kernel("Oops", regs, 0);
+
+        info.si_signo = inf->sig;
+        info.si_errno = 0;
+        info.si_code  = inf->code;
+        info.si_addr  = (void __user *)addr;
+        notify_die("", regs, &info, fsr, 0);
 }
 
 asmlinkage void
diff --git a/include/asm-arm/system.h b/include/asm-arm/system.h
index cdf49f442fd2..2f44b2044214 100644
--- a/include/asm-arm/system.h
+++ b/include/asm-arm/system.h
@@ -85,7 +85,9 @@ struct pt_regs;
 void die(const char *msg, struct pt_regs *regs, int err)
                 __attribute__((noreturn));
 
-void die_if_kernel(const char *str, struct pt_regs *regs, int err);
+struct siginfo;
+void notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
+                unsigned long err, unsigned long trap);
 
 void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
                                        struct pt_regs *),