[PATCH] x86_64: make trap information available to die notification handlers

This adjusts things so that handlers of the die() notifier will have
sufficient information about the trap currently being handled. It also
adjusts the notify_die() prototype to (again) match that of i386.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 18 insertions, 15 deletions

diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index 0fd17e01de06..0266b523e8d0 100644
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -382,7 +382,7 @@ void __die(const char * str, struct pt_regs * regs, long err)
         printk("DEBUG_PAGEALLOC");
 #endif
         printk("\n");
-        notify_die(DIE_OOPS, (char *)str, regs, err, 255, SIGSEGV);
+        notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
         show_registers(regs);
         /* Executive summary in case the oops scrolled away */
         printk(KERN_ALERT "RIP ");
@@ -421,19 +421,20 @@ static void __kprobes do_trap(int trapnr, int signr, char *str,
                               struct pt_regs * regs, long error_code,
                               siginfo_t *info)
 {
+        struct task_struct *tsk = current;
+
         conditional_sti(regs);
 
-        if (user_mode(regs)) {
-                struct task_struct *tsk = current;
+        tsk->thread.error_code = error_code;
+        tsk->thread.trap_no = trapnr;
 
+        if (user_mode(regs)) {
                 if (exception_trace && unhandled_signal(tsk, signr))
                         printk(KERN_INFO
                                "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n",
                                tsk->comm, tsk->pid, str,
                                regs->rip,regs->rsp,error_code); 
 
-                tsk->thread.error_code = error_code;
-                tsk->thread.trap_no = trapnr;
                 if (info)
                         force_sig_info(signr, info, tsk);
                 else
@@ -493,19 +494,20 @@ DO_ERROR( 8, SIGSEGV, "double fault", double_fault)
 asmlinkage void __kprobes do_general_protection(struct pt_regs * regs,
                                                 long error_code)
 {
+        struct task_struct *tsk = current;
+
         conditional_sti(regs);
 
-        if (user_mode(regs)) {
-                struct task_struct *tsk = current;
+        tsk->thread.error_code = error_code;
+        tsk->thread.trap_no = 13;
 
+        if (user_mode(regs)) {
                 if (exception_trace && unhandled_signal(tsk, SIGSEGV))
                         printk(KERN_INFO
                        "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n",
                                tsk->comm, tsk->pid,
                                regs->rip,regs->rsp,error_code); 
 
-                tsk->thread.error_code = error_code;
-                tsk->thread.trap_no = 13;
                 force_sig(SIGSEGV, tsk);
                 return;
         } 
@@ -568,7 +570,7 @@ asmlinkage void default_do_nmi(struct pt_regs *regs)
                 reason = get_nmi_reason();
 
         if (!(reason & 0xc0)) {
-                if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 0, SIGINT)
+                if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT)
                                                                 == NOTIFY_STOP)
                         return;
 #ifdef CONFIG_X86_LOCAL_APIC
@@ -584,7 +586,7 @@ asmlinkage void default_do_nmi(struct pt_regs *regs)
                 unknown_nmi_error(reason, regs);
                 return;
         }
-        if (notify_die(DIE_NMI, "nmi", regs, reason, 0, SIGINT) == NOTIFY_STOP)
+        if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
                 return; 
 
         /* AK: following checks seem to be broken on modern chipsets. FIXME */
@@ -693,7 +695,7 @@ clear_TF_reenable:
         regs->eflags &= ~TF_MASK;
 }
 
-static int kernel_math_error(struct pt_regs *regs, char *str)
+static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
 {
         const struct exception_table_entry *fixup;
         fixup = search_exception_tables(regs->rip);
@@ -701,8 +703,9 @@ static int kernel_math_error(struct pt_regs *regs, char *str)
                 regs->rip = fixup->fixup;
                 return 1;
         }
-        notify_die(DIE_GPF, str, regs, 0, 16, SIGFPE);
+        notify_die(DIE_GPF, str, regs, 0, trapnr, SIGFPE);
         /* Illegal floating point operation in the kernel */
+        current->thread.trap_no = trapnr;
         die(str, regs, 0);
         return 0;
 }
@@ -721,7 +724,7 @@ asmlinkage void do_coprocessor_error(struct pt_regs *regs)
 
         conditional_sti(regs);
         if (!user_mode(regs) &&
-            kernel_math_error(regs, "kernel x87 math error"))
+            kernel_math_error(regs, "kernel x87 math error", 16))
                 return;
 
         /*
@@ -790,7 +793,7 @@ asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs)
 
         conditional_sti(regs);
         if (!user_mode(regs) &&
-                kernel_math_error(regs, "kernel simd math error"))
+                kernel_math_error(regs, "kernel simd math error", 19))
                 return;
 
         /*