x86: last of trivial fault_32|64.c unification

Comments, indentation, printk format.

Uses task_pid_nr() on X86_64 now, but this is always defined
to task->pid.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/mm/fault_32.c b/arch/x86/mm/fault_32.c
index 52c13d2e011ee45d9822b82479c8361d4f24d092..31113deeb7c06f55c781d5b9cc40b5355ef604dc 100644 (file)
--- a/arch/x86/mm/fault_32.c
+++ b/arch/x86/mm/fault_32.c
@@ -36,10 +36,10 @@
  *     bit 3 == 1 means use of reserved bit detected
  *     bit 4 == 1 means fault was an instruction fetch
  */
-#define PF_PROT        (1<<0)
+#define PF_PROT                (1<<0)
 #define PF_WRITE       (1<<1)
-#define PF_USER        (1<<2)
-#define PF_RSVD        (1<<3)
+#define PF_USER                (1<<2)
+#define PF_RSVD                (1<<3)
 #define PF_INSTR       (1<<4)
 
 static inline int notify_page_fault(struct pt_regs *regs)
@@ -460,11 +460,15 @@ bad_area_nosemaphore:
 
                if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
                    printk_ratelimit()) {
-                       printk("%s%s[%d]: segfault at %08lx ip %08lx "
-                           "sp %08lx error %lx\n",
-                           task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
-                           tsk->comm, task_pid_nr(tsk), address, regs->ip,
-                           regs->sp, error_code);
+                       printk(
+#ifdef CONFIG_X86_32
+                       "%s%s[%d]: segfault at %08lx ip %08lx sp %08lx error %lx\n",
+#else
+                       "%s%s[%d]: segfault at %lx ip %lx sp %lx error %lx\n",
+#endif
+                       task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
+                       tsk->comm, task_pid_nr(tsk), address, regs->ip,
+                       regs->sp, error_code);
                }
                tsk->thread.cr2 = address;
                /* Kernel addresses are always protection faults */

diff --git a/arch/x86/mm/fault_64.c b/arch/x86/mm/fault_64.c
index c6b3ad515cf12c5e071c0e2761fd049db4be914f..c48d95c306df9e05b3110cbac6f1e3f64aa4d4de 100644 (file)
--- a/arch/x86/mm/fault_64.c
+++ b/arch/x86/mm/fault_64.c
@@ -440,8 +440,11 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
        if (!(vma->vm_flags & VM_GROWSDOWN))
                goto bad_area;
        if (error_code & PF_USER) {
-               /* Allow userspace just enough access below the stack pointer
-                * to let the 'enter' instruction work.
+               /*
+                * Accessing the stack below %sp is always a bug.
+                * The large cushion allows instructions like enter
+                * and pusha to work.  ("enter $65535,$31" pushes
+                * 32 pointers and then decrements %sp by 65535.)
                 */
                if (address + 65536 + 32 * sizeof(unsigned long) < regs->sp)
                        goto bad_area;
@@ -522,10 +525,14 @@ bad_area_nosemaphore:
                if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) &&
                    printk_ratelimit()) {
                        printk(
-                      "%s%s[%d]: segfault at %lx ip %lx sp %lx error %lx\n",
-                                       tsk->pid > 1 ? KERN_INFO : KERN_EMERG,
-                                       tsk->comm, tsk->pid, address, regs->ip,
-                                       regs->sp, error_code);
+#ifdef CONFIG_X86_32
+                       "%s%s[%d]: segfault at %08lx ip %08lx sp %08lx error %lx\n",
+#else
+                       "%s%s[%d]: segfault at %lx ip %lx sp %lx error %lx\n",
+#endif
+                       task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
+                       tsk->comm, task_pid_nr(tsk), address, regs->ip,
+                       regs->sp, error_code);
                }
 
                tsk->thread.cr2 = address;
@@ -609,10 +616,12 @@ LIST_HEAD(pgd_list);
 
 void vmalloc_sync_all(void)
 {
-       /* Note that races in the updates of insync and start aren't
-          problematic:
-          insync can only get set bits added, and updates to start are only
-          improving performance (without affecting correctness if undone). */
+       /*
+        * Note that races in the updates of insync and start aren't
+        * problematic: insync can only get set bits added, and updates to
+        * start are only improving performance (without affecting correctness
+        * if undone).
+        */
        static DECLARE_BITMAP(insync, PTRS_PER_PGD);
        static unsigned long start = VMALLOC_START & PGDIR_MASK;
        unsigned long address;