Just a very quick question about paging of linux
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clementttttttttt
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Just a very quick question about paging of linux
Did Linux identity mapped the pages to the whole memory(paging)?
Re: Just a very quick question about paging of linux
That terse question deserves an equally terse answer: No.
At least, if I understand your horribly phrased question right. Linux does not, in fact, identity map anything, except maybe a trampoline on boot up. That will then get mapped out.
At least, if I understand your horribly phrased question right. Linux does not, in fact, identity map anything, except maybe a trampoline on boot up. That will then get mapped out.
Carpe diem!
Re: Just a very quick question about paging of linux
Original Linux identity mapped the first 8M (all the RAM Linus had) during boot. See head.s.clementttttttttt wrote:Did Linux identity mapped the pages to the whole memory(paging)?
Then as tasks were started, the mm replaced the identity mapping with per-task mappings.
Cheers,
bzt
Re: Just a very quick question about paging of linux
bzt wrote:Original Linux identity mapped the first 8M (all the RAM Linus had) during boot. See head.s.clementttttttttt wrote:Did Linux identity mapped the pages to the whole memory(paging)?
And by the way, this technique wasn't just used in the very early versions (the link goes to the original release 0.0.1). 2.x kernels continued to do this in the kernel bootstrap code.