x86/dumpstack: Rename thread_struct::sig_on_uaccess_error to sig_on_uaccess_err

Rename it to match the thread_struct::uaccess_err pattern and also
because it was too long.

Cc: Andy Lutomirski <[e-mail]>
Cc: Borislav Petkov <[e-mail]>
Cc: Brian Gerst <[e-mail]>
Cc: Denys Vlasenko <[e-mail]>
Cc: H. Peter Anvin <[e-mail]>
Cc: Josh Poimboeuf <[e-mail]>
Cc: Linus Torvalds <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: [e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

arch/x86/entry/vsyscall/vsyscall_64.c

···
 {
 	/*
 	 * XXX: if access_ok, get_user, and put_user handled
-	 * sig_on_uaccess_error, this could go away.
+	 * sig_on_uaccess_err, this could go away.
 	 */
 
 	if (!access_ok(VERIFY_WRITE, (void __user *)ptr, size)) {
···
 	struct task_struct *tsk;
 	unsigned long caller;
 	int vsyscall_nr, syscall_nr, tmp;
-	int prev_sig_on_uaccess_error;
+	int prev_sig_on_uaccess_err;
 	long ret;
 
 	/*
···
 	 * With a real vsyscall, page faults cause SIGSEGV.  We want to
 	 * preserve that behavior to make writing exploits harder.
 	 */
-	prev_sig_on_uaccess_error = current->thread.sig_on_uaccess_error;
-	current->thread.sig_on_uaccess_error = 1;
+	prev_sig_on_uaccess_err = current->thread.sig_on_uaccess_err;
+	current->thread.sig_on_uaccess_err = 1;
 
 	ret = -EFAULT;
 	switch (vsyscall_nr) {
···
 		break;
 	}
 
-	current->thread.sig_on_uaccess_error = prev_sig_on_uaccess_error;
+	current->thread.sig_on_uaccess_err = prev_sig_on_uaccess_err;
 
 check_fault:
 	if (ret == -EFAULT) {

arch/x86/include/asm/processor.h

···
 	/* Max allowed port in the bitmap, in bytes: */
 	unsigned		io_bitmap_max;
 
-	unsigned int		sig_on_uaccess_error:1;
+	unsigned int		sig_on_uaccess_err:1;
 	unsigned int		uaccess_err:1;	/* uaccess failed */
 
 	/* Floating point and extended processor state */

arch/x86/mm/fault.c

···
 		 * In this case we need to make sure we're not recursively
 		 * faulting through the emulate_vsyscall() logic.
 		 */
-		if (current->thread.sig_on_uaccess_error && signal) {
+		if (current->thread.sig_on_uaccess_err && signal) {
 			tsk->thread.trap_nr = X86_TRAP_PF;
 			tsk->thread.error_code = error_code | PF_USER;
 			tsk->thread.cr2 = address;