linux-kernel - Question on Memory management unit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <CALyraeP41AEZFD=cHZT_PYgUZ+nrvDfTMQ1t9qtuFJ-cOEssiQ@mail.gmail.com>
Date:	Sat, 8 Dec 2012 19:08:08 -0500
From:	Sri Ram Vemulpali <sri.ram.gmu06@...il.com>
To:	linux-newbie@...r.kernel.org,
	linux-kernel-mail <linux-kernel@...r.kernel.org>
Subject: Question on Memory management unit

Hi Guys,

I have question on memory management in linux kernel.

>From my understanding memory is divided into 3GB and 1GB for 32-bit
architectures. 1GB is allocated to kernel space and 3GB is allocated
to user space.

To access any memory in kernel space, it should be mapped in to kernel
virtual address space.

My question is how do we know kernel address space (virtual address).
Can we recognize a range of addresses, if so what is that range of
kernel virtual address?

What function returns kernel virtual address. Or do we need to map to
get kernel virtual address.

I know kmalloc returns logical address and vmalloc returns virtual address.
And all these addresses should go through MMU to access physical
memory. So there will be page mappings in kernel for these addresses.
Is this true?

Thanks in advance.
-- 
Regards,
Sri.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/