CODEWITHSUNDEEP
linux-kernelkernel
Vi Nguyen
Vi Nguyen

Reputation: 359

what is the function of CONFIG_X86_WP_WORKS_OK?

can someone help me to understand this declaration: CONFIG_X86_WP_WORKS_OK in kernel config? what is the function of it? and how it work?

Upvotes: 2

Views: 158

Answers (1)

Ranjith Ruban
Ranjith Ruban

Reputation: 537

Require working memory write protect

CONFIG_X86_WP_WORKS_OK

So if you enable this option, the kernel assumes your processor handles writing to pages while in supervisor mode properly.

http://lkml.indiana.edu/hypermail/linux/kernel/0003.1/0009.html

the above is an old thread. recent code does not seems to have this comment.

WP Write protect Determines whether the CPU can write to pages marked read-only

http://en.wikipedia.org/wiki/Control_register

From below

http://src3.org/#RHEL6-2.6.32+220.el6/arch/x86/mm/init_32.c#L845

there is a check for WP bit in cpu and find non-working WP bit and panic system.

http://vulnfactory.org/blog/2011/08/12/wp-safe-or-not/

Upvotes: 1

Related Questions