- 2.6.17 port work build breaks, but the patch set is relativly stable

[linux-flexiantxendom0-3.2.10.git] / arch / x86_64 / kernel / traps.c

diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index aad4105..f7f2b7a 100644 (file)
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -27,7 +27,6 @@
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
-#include <linux/dump.h>
 #include <linux/moduleparam.h>
 #include <linux/nmi.h>
 #include <linux/kprobes.h>
@@ -49,8 +48,6 @@
 #include <asm/proto.h>
 #include <asm/nmi.h>
 
-extern struct gate_struct idt_table[256]; 
-
 asmlinkage void divide_error(void);
 asmlinkage void debug(void);
 asmlinkage void nmi(void);
@@ -73,18 +70,20 @@ asmlinkage void alignment_check(void);
 asmlinkage void machine_check(void);
 asmlinkage void spurious_interrupt_bug(void);
 
-struct notifier_block *die_chain;
-static DEFINE_SPINLOCK(die_notifier_lock);
+ATOMIC_NOTIFIER_HEAD(die_chain);
 
 int register_die_notifier(struct notifier_block *nb)
 {
-       int err = 0;
-       unsigned long flags;
-       spin_lock_irqsave(&die_notifier_lock, flags);
-       err = notifier_chain_register(&die_chain, nb);
-       spin_unlock_irqrestore(&die_notifier_lock, flags);
-       return err;
+       vmalloc_sync_all();
+       return atomic_notifier_chain_register(&die_chain, nb);
+}
+EXPORT_SYMBOL(register_die_notifier);
+
+int unregister_die_notifier(struct notifier_block *nb)
+{
+       return atomic_notifier_chain_unregister(&die_chain, nb);
 }
+EXPORT_SYMBOL(unregister_die_notifier);
 
 static inline void conditional_sti(struct pt_regs *regs)
 {
@@ -103,6 +102,8 @@ static inline void preempt_conditional_cli(struct pt_regs *regs)
 {
        if (regs->eflags & X86_EFLAGS_IF)
                local_irq_disable();
+       /* Make sure to not schedule here because we could be running
+          on an exception stack. */
        preempt_enable_no_resched();
 }
 
@@ -124,7 +125,7 @@ int printk_address(unsigned long address)
        if (!modname) 
                modname = delim = "";           
         return printk("<%016lx>{%s%s%s%s%+ld}",
-                     address,delim,modname,delim,symname,offset); 
+                     address, delim, modname, delim, symname, offset); 
 } 
 #else
 int printk_address(unsigned long address)
@@ -336,13 +337,12 @@ void show_registers(struct pt_regs *regs)
                show_stack(NULL, (unsigned long*)rsp);
 
                printk("\nCode: ");
-               if(regs->rip < PAGE_OFFSET)
+               if (regs->rip < PAGE_OFFSET)
                        goto bad;
 
-               for(i=0;i<20;i++)
-               {
+               for (i=0; i<20; i++) {
                        unsigned char c;
-                       if(__get_user(c, &((unsigned char*)regs->rip)[i])) {
+                       if (__get_user(c, &((unsigned char*)regs->rip)[i])) {
 bad:
                                printk(" Bad RIP value.");
                                break;
@@ -441,7 +441,6 @@ void __kprobes __die(const char * str, struct pt_regs * regs, long err)
        sysfs_printk_last_file();
        notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV);
        show_registers(regs);
-       dump((char *)str, regs);
        /* Executive summary in case the oops scrolled away */
        printk(KERN_ALERT "RIP ");
        printk_address(regs->rip); 
@@ -474,7 +473,6 @@ void __kprobes die_nmi(char *str, struct pt_regs *regs)
                crash_kexec(regs);
        if (panic_on_timeout || panic_on_oops)
                panic("nmi watchdog");
-       dump(str ,regs);
        printk("console shuts up ...\n");
        oops_end(flags);
        nmi_exit();
@@ -488,8 +486,6 @@ static void __kprobes do_trap(int trapnr, int signr, char *str,
 {
        struct task_struct *tsk = current;
 
-       conditional_sti(regs);
-
        tsk->thread.error_code = error_code;
        tsk->thread.trap_no = trapnr;
 
@@ -498,7 +494,7 @@ static void __kprobes do_trap(int trapnr, int signr, char *str,
                        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); 
+                              regs->rip, regs->rsp, error_code); 
 
                if (info)
                        force_sig_info(signr, info, tsk);
@@ -512,9 +508,9 @@ static void __kprobes do_trap(int trapnr, int signr, char *str,
        {            
                const struct exception_table_entry *fixup;
                fixup = search_exception_tables(regs->rip);
-               if (fixup) {
+               if (fixup)
                        regs->rip = fixup->fixup;
-               } else  
+               else    
                        die(str, regs, error_code);
                return;
        }
@@ -526,6 +522,7 @@ asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
        if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
                                                        == NOTIFY_STOP) \
                return; \
+       conditional_sti(regs);                                          \
        do_trap(trapnr, signr, str, regs, error_code, NULL); \
 }
 
@@ -540,6 +537,7 @@ asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
        if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
                                                        == NOTIFY_STOP) \
                return; \
+       conditional_sti(regs);                                          \
        do_trap(trapnr, signr, str, regs, error_code, &info); \
 }
 
@@ -553,7 +551,17 @@ DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
 DO_ERROR(11, SIGBUS,  "segment not present", segment_not_present)
 DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
 DO_ERROR(18, SIGSEGV, "reserved", reserved)
-DO_ERROR(12, SIGBUS,  "stack segment", stack_segment)
+
+/* Runs on IST stack */
+asmlinkage void do_stack_segment(struct pt_regs *regs, long error_code)
+{
+       if (notify_die(DIE_TRAP, "stack segment", regs, error_code,
+                       12, SIGBUS) == NOTIFY_STOP)
+               return;
+       preempt_conditional_sti(regs);
+       do_trap(12, SIGBUS, "stack segment", regs, error_code, NULL);
+       preempt_conditional_cli(regs);
+}
 
 asmlinkage void do_double_fault(struct pt_regs * regs, long error_code)
 {
@@ -587,7 +595,7 @@ asmlinkage void __kprobes do_general_protection(struct pt_regs * regs,
                        printk(KERN_INFO
                       "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n",
                               tsk->comm, tsk->pid,
-                              regs->rip,regs->rsp,error_code); 
+                              regs->rip, regs->rsp, error_code); 
 
                force_sig(SIGSEGV, tsk);
                return;
@@ -687,8 +695,9 @@ asmlinkage void __kprobes do_int3(struct pt_regs * regs, long error_code)
        if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) == NOTIFY_STOP) {
                return;
        }
+       preempt_conditional_sti(regs);
        do_trap(3, SIGTRAP, "int3", regs, error_code, NULL);
-       return;
+       preempt_conditional_cli(regs);
 }
 
 /* Help handler running on IST stack to switch back to user stack
@@ -993,14 +1002,14 @@ void __init trap_init(void)
 static int __init oops_dummy(char *s)
 { 
        panic_on_oops = 1;
-       return -1; 
+       return 1;
 } 
 __setup("oops=", oops_dummy); 
 
 static int __init kstack_setup(char *s)
 {
        kstack_depth_to_print = simple_strtoul(s,NULL,0);
-       return 0;
+       return 1;
 }
 __setup("kstack=", kstack_setup);