sparc: Support show_unhandled_signals.

Just faults right now, will add other traps later.

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 91 insertions, 49 deletions

diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c
index a3413acb8f12..ec8f22c681ef 100644
--- a/arch/sparc/mm/fault_32.c
+++ b/arch/sparc/mm/fault_32.c
@@ -35,6 +35,8 @@
 
 extern int prom_node_root;
 
+int show_unhandled_signals = 1;
+
 /* At boot time we determine these two values necessary for setting
  * up the segment maps and page table entries (pte's).
  */
@@ -149,6 +151,45 @@ asmlinkage int lookup_fault(unsigned long pc, unsigned long ret_pc,
         return 0;
 }
 
+static inline void
+show_signal_msg(struct pt_regs *regs, int sig, int code,
+                unsigned long address, struct task_struct *tsk)
+{
+        if (!unhandled_signal(tsk, sig))
+                return;
+
+        if (!printk_ratelimit())
+                return;
+
+        printk("%s%s[%d]: segfault at %lx ip %p (rpc %p) sp %p error %x",
+               task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
+               tsk->comm, task_pid_nr(tsk), address,
+               (void *)regs->pc, (void *)regs->u_regs[UREG_I7],
+               (void *)regs->u_regs[UREG_FP], code);
+
+        print_vma_addr(KERN_CONT " in ", regs->pc);
+
+        printk(KERN_CONT "\n");
+}
+
+static void __do_fault_siginfo(int code, int sig, struct pt_regs *regs,
+                               unsigned long addr)
+{
+        siginfo_t info;
+
+        info.si_signo = sig;
+        info.si_code = code;
+        info.si_errno = 0;
+        info.si_addr = (void __user *) addr;
+        info.si_trapno = 0;
+
+        if (unlikely(show_unhandled_signals))
+                show_signal_msg(regs, sig, info.si_code,
+                                addr, current);
+
+        force_sig_info (sig, &info, current);
+}
+
 extern unsigned long safe_compute_effective_address(struct pt_regs *,
                                                     unsigned int);
 
@@ -168,6 +209,14 @@ static unsigned long compute_si_addr(struct pt_regs *regs, int text_fault)
         return safe_compute_effective_address(regs, insn);
 }
 
+static noinline void do_fault_siginfo(int code, int sig, struct pt_regs *regs,
+                                      int text_fault)
+{
+        unsigned long addr = compute_si_addr(regs, text_fault);
+
+        __do_fault_siginfo(code, sig, regs, addr);
+}
+
 asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
                                unsigned long address)
 {
@@ -176,9 +225,8 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
         struct mm_struct *mm = tsk->mm;
         unsigned int fixup;
         unsigned long g2;
-        siginfo_t info;
         int from_user = !(regs->psr & PSR_PS);
-        int fault;
+        int fault, code;
 
         if(text_fault)
                 address = regs->pc;
@@ -195,7 +243,7 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
         if (!ARCH_SUN4C && address >= TASK_SIZE)
                 goto vmalloc_fault;
 
-        info.si_code = SEGV_MAPERR;
+        code = SEGV_MAPERR;
 
         /*
          * If we're in an interrupt or have no user
@@ -229,7 +277,7 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
          * we can handle it..
          */
 good_area:
-        info.si_code = SEGV_ACCERR;
+        code = SEGV_ACCERR;
         if(write) {
                 if(!(vma->vm_flags & VM_WRITE))
                         goto bad_area;
@@ -273,18 +321,8 @@ bad_area:
 
 bad_area_nosemaphore:
         /* User mode accesses just cause a SIGSEGV */
-        if(from_user) {
-#if 0
-                printk("Fault whee %s [%d]: segfaults at %08lx pc=%08lx\n",
-                       tsk->comm, tsk->pid, address, regs->pc);
-#endif
-                info.si_signo = SIGSEGV;
-                info.si_errno = 0;
-                /* info.si_code set above to make clear whether
-                   this was a SEGV_MAPERR or SEGV_ACCERR fault.  */
-                info.si_addr = (void __user *)compute_si_addr(regs, text_fault);
-                info.si_trapno = 0;
-                force_sig_info (SIGSEGV, &info, tsk);
+        if (from_user) {
+                do_fault_siginfo(code, SIGSEGV, regs, text_fault);
                 return;
         }
 
@@ -335,12 +373,7 @@ out_of_memory:
 
 do_sigbus:
         up_read(&mm->mmap_sem);
-        info.si_signo = SIGBUS;
-        info.si_errno = 0;
-        info.si_code = BUS_ADRERR;
-        info.si_addr = (void __user *) compute_si_addr(regs, text_fault);
-        info.si_trapno = 0;
-        force_sig_info (SIGBUS, &info, tsk);
+        do_fault_siginfo(BUS_ADRERR, SIGBUS, regs, text_fault);
         if (!from_user)
                 goto no_context;
 
@@ -466,14 +499,10 @@ static void force_user_fault(unsigned long address, int write)
         struct vm_area_struct *vma;
         struct task_struct *tsk = current;
         struct mm_struct *mm = tsk->mm;
-        siginfo_t info;
+        int code;
 
-        info.si_code = SEGV_MAPERR;
+        code = SEGV_MAPERR;
 
-#if 0
-        printk("wf<pid=%d,wr=%d,addr=%08lx>\n",
-               tsk->pid, write, address);
-#endif
         down_read(&mm->mmap_sem);
         vma = find_vma(mm, address);
         if(!vma)
@@ -485,7 +514,7 @@ static void force_user_fault(unsigned long address, int write)
         if(expand_stack(vma, address))
                 goto bad_area;
 good_area:
-        info.si_code = SEGV_ACCERR;
+        code = SEGV_ACCERR;
         if(write) {
                 if(!(vma->vm_flags & VM_WRITE))
                         goto bad_area;
@@ -502,27 +531,12 @@ good_area:
         return;
 bad_area:
         up_read(&mm->mmap_sem);
-#if 0
-        printk("Window whee %s [%d]: segfaults at %08lx\n",
-               tsk->comm, tsk->pid, address);
-#endif
-        info.si_signo = SIGSEGV;
-        info.si_errno = 0;
-        /* info.si_code set above to make clear whether
-           this was a SEGV_MAPERR or SEGV_ACCERR fault.  */
-        info.si_addr = (void __user *) address;
-        info.si_trapno = 0;
-        force_sig_info (SIGSEGV, &info, tsk);
+        __do_fault_siginfo(code, SIGSEGV, tsk->thread.kregs, address);
         return;
 
 do_sigbus:
         up_read(&mm->mmap_sem);
-        info.si_signo = SIGBUS;
-        info.si_errno = 0;
-        info.si_code = BUS_ADRERR;
-        info.si_addr = (void __user *) address;
-        info.si_trapno = 0;
-        force_sig_info (SIGBUS, &info, tsk);
+        __do_fault_siginfo(BUS_ADRERR, SIGBUS, tsk->thread.kregs, address);
 }
 
 void window_overflow_fault(void)
diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c
index b9d4ff02b8fc..f92ce56a8b22 100644
--- a/arch/sparc/mm/fault_64.c
+++ b/arch/sparc/mm/fault_64.c
@@ -32,6 +32,8 @@
 #include <asm/sections.h>
 #include <asm/mmu_context.h>
 
+int show_unhandled_signals = 1;
+
 static inline __kprobes int notify_page_fault(struct pt_regs *regs)
 {
         int ret = 0;
@@ -128,22 +130,48 @@ outret:
         return insn;
 }
 
+static inline void
+show_signal_msg(struct pt_regs *regs, int sig, int code,
+                unsigned long address, struct task_struct *tsk)
+{
+        if (!unhandled_signal(tsk, sig))
+                return;
+
+        if (!printk_ratelimit())
+                return;
+
+        printk("%s%s[%d]: segfault at %lx ip %p (rpc %p) sp %p error %x",
+               task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
+               tsk->comm, task_pid_nr(tsk), address,
+               (void *)regs->tpc, (void *)regs->u_regs[UREG_I7],
+               (void *)regs->u_regs[UREG_FP], code);
+
+        print_vma_addr(KERN_CONT " in ", regs->tpc);
+
+        printk(KERN_CONT "\n");
+}
+
 extern unsigned long compute_effective_address(struct pt_regs *, unsigned int, unsigned int);
 
 static void do_fault_siginfo(int code, int sig, struct pt_regs *regs,
                              unsigned int insn, int fault_code)
 {
+        unsigned long addr;
         siginfo_t info;
 
         info.si_code = code;
         info.si_signo = sig;
         info.si_errno = 0;
         if (fault_code & FAULT_CODE_ITLB)
-                info.si_addr = (void __user *) regs->tpc;
+                addr = regs->tpc;
         else
-                info.si_addr = (void __user *)
-                        compute_effective_address(regs, insn, 0);
+                addr = compute_effective_address(regs, insn, 0);
+        info.si_addr = (void __user *) addr;
         info.si_trapno = 0;
+
+        if (unlikely(show_unhandled_signals))
+                show_signal_msg(regs, sig, code, addr, current);
+
         force_sig_info(sig, &info, current);
 }