<s>
KernelCare	B-Application
is	O
a	O
live	O
kernel	B-Operating_System
patching	O
service	O
that	O
provides	O
security	O
patches	O
and	O
bugfixes	O
for	O
a	O
range	O
of	O
popular	O
Linux	B-Operating_System
kernels	I-Operating_System
that	O
can	O
be	O
installed	O
without	O
rebooting	B-Device
the	O
system	O
.	O
</s>
<s>
KernelCare	B-Application
software	O
is	O
a	O
commercial	O
product	O
.	O
</s>
<s>
KernelCare	B-Application
agent	O
resides	O
on	O
user	O
's	O
server	B-Application
.	O
</s>
<s>
It	O
periodically	O
checks	O
in	O
with	O
KernelCare	B-Application
distribution	O
servers	O
.	O
</s>
<s>
If	O
there	O
are	O
new	O
patches	O
available	O
for	O
the	O
currently	O
running	O
kernel	B-Operating_System
,	O
KernelCare	B-Application
agent	O
downloads	O
and	O
applies	O
those	O
patches	O
to	O
the	O
running	O
kernel	B-Operating_System
.	O
</s>
<s>
A	O
KernelCare	B-Application
patch	O
is	O
a	O
piece	O
of	O
code	O
used	O
to	O
substitute	O
vulnerable	O
or	O
buggy	O
code	O
in	O
a	O
kernel	B-Operating_System
.	O
</s>
<s>
The	O
resulting	O
code	O
modifications	O
are	O
safely	O
applied	O
to	O
the	O
running	O
kernel	B-Operating_System
.	O
</s>
<s>
A	O
special	O
KernelCare	B-Application
kernel	B-Application
module	I-Application
applies	O
the	O
patches	O
.	O
</s>
<s>
It	O
loads	O
the	O
patches	O
into	O
the	O
kernel	B-Operating_System
address	O
space	O
,	O
sets	O
up	O
the	O
relocations	O
(	O
i.e.	O
,	O
fixes	O
the	O
references	O
to	O
the	O
original	O
kernel	B-Operating_System
code	O
and	O
data	O
)	O
,	O
and	O
safely	O
switches	O
the	O
execution	O
path	O
from	O
the	O
original	O
code	O
to	O
updated	O
code	O
blocks	O
.	O
</s>
<s>
The	O
code	O
ensures	O
the	O
patch	O
is	O
applied	O
safely	O
so	O
the	O
CPU	B-Device
does	O
n't	O
execute	O
the	O
original	O
code	O
blocks	O
at	O
the	O
same	O
moment	O
when	O
switching	O
to	O
a	O
new	O
version	O
.	O
</s>
