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A comment on Malloc Never Fails (2012). Parent comment

Re:Malloc Never Fails (2012) by lifthrasiir on Monday June 10, 2019 @05:28AM (#20145128)
But x86-64 divides the 48-bit address space into two halves, only one of which is available in the user mode.
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Re:Malloc Never Fails (2012) by monocasa on Monday June 10, 2019 @01:14PM (#20148686)
To be fair, there's nothing that says the higher half _has_ to be entirely kernel mode. Only that bits 63 through 48 have to be the same value.

And Intel has a spec out for a PML5 page table, giving you 57 total virtual address bits.

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