Linux Delete files before 15days

Delete files before 15 days
   find . -mtime +15 -exec rm {} \;  

Linux kernel.tainted

kernel.tainted:

Non-zero if the kernel has been tainted.  Numeric values, which can be ORed together:

   1 - A module with a non-GPL license has been loaded, this includes modules with no license.
       Set by modutils >= 2.4.9 and module-init-tools.
   2 - A module was force loaded by insmod -f.
       Set by modutils >= 2.4.9 and module-init-tools.
   4 - Unsafe SMP processors: SMP with CPUs not designed for SMP.
   8 - A module was forcibly unloaded from the system by rmmod -f.
  16 - A hardware machine check error occurred on the system.   (mcelog)
  32 - A bad page was discovered on the system.
  64 - The user has asked that the system be marked "tainted".  This could be because they are running software that directly modifies the hardware, or for other reasons.
 128 - The system has died.
 256 - The ACPI DSDT has been overridden with one supplied by the user instead of using the one provided by the hardware.
 512 - A kernel warning has occurred.
1024 - A module from drivers/staging was loaded.
2048 - The system is working around a severe firmware bug.
4096 - An out-of-tree module has been loaded.