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From: gprabhunath@gmail.com (Prabhunath G)
To: kernelnewbies@lists.kernelnewbies.org
Subject: Vmalloc
Date: Wed, 7 Sep 2016 00:06:48 +0530	[thread overview]
Message-ID: <CACPKTAMn9bsACveJXRGqq9MyMP9WZSgV1Gv53iQpf2-no_RcrQ@mail.gmail.com> (raw)
In-Reply-To: <CAMGjyMuC3Bg-o3MJ4ZnNP_OM2VSQiqi+COtpbqHUmfEB1KGQTA@mail.gmail.com>

vmalloc() may allocate non-contiguous physical memory and map it to
contiguous kernel virtual address.

For eg. if you ask for 10 page frames of physical memory i.e. 10 * 4K,
vmalloc() will scout for 10 page frames of physical memory, they need not
be contiguous,
and map them to contiguous kernel virtual address (last 128 MB of virtual
address in a 3G/1G partition, assuming >= 1GB of RAM)

 This could be of some help and is also somewhat extension of your question
https://lists.kernelnewbies.org/pipermail/kernelnewbies/2011-June/002335.html


On Tue, Sep 6, 2016 at 8:12 PM, Er Krishna <erkrishna@gmail.com> wrote:

> > Hi all
> >
> > I have one confusion, so asking this question for understanding:
> >
> > Vmalloc return address are virtually contiguous or not ?
> >
> > Basically vmalloc return non contiguous memory from ram which may not be
> one to one mapped in process kernel address space .
> >
> > Is my above understanding correct?
> >
> > Thanks
> > Krishna
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
>


-- 
Regards,
Prabhunath G
Linux Trainer
Bangalore
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      reply	other threads:[~2016-09-06 18:36 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CAMGjyMubkhwFwHyfYHeJH4fUXOpexCtZ1RLgWDTRSw2Vf-86wg@mail.gmail.com>
2016-09-06 14:42 ` Vmalloc Er Krishna
2016-09-06 18:36   ` Prabhunath G [this message]

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