use strict;
use warnings;

my %msgs;
while (<DATA>) {
    s/^\s+//;
    chomp;
    $msgs{$_}++;
}

# Sort by number of occurrences and only show top 8:
my $i = 0;
for my $m (sort {$msgs{$b} <=> $msgs{$a}} keys %msgs) {
    print "$msgs{$m} $m\n";
    $i++;
    last if $i == 8;
}

__DATA__
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol unlock_page
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol generic_file_read
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol generic_file_write
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol generic_file_mmap
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol generic_file_sendfile
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: disagrees about version of symbol zone_table
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol zone_table
     Mar  9 08:15:05  gen-vcs11 kernel: kjslahdisagrees about version of symbol unlock_page
Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol unlock_page
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol filemap_fdatawrite
     Mar  9 08:15:05  gen-vcs11 kernel: kjslah: Unknown symbol find_or_create_page