`kl-p2v`¶

Physical to virtual

Canonical: kernlens-p2v
Category: addresses & page tables
Synopsis: kl-p2v [-h] paddr

Translates a physical address to its direct-map virtual address and prints the struct page and type, the same three facts as kl-pageinfo.

Options¶

Option	Argument	Meaning
	—	physical address to translate

A free page¶

Invocation¶

kl-p2v 0x400000

Output¶

Physical: 0x400000
Virtual: 0xffff90c340400000
page: 0xffffcd3b80010000
PFN: 1024  type: buddy
refcount: 0

Reading it¶

Virtual is page_offset_base + phys exactly, because that is what the direct map is. The struct page and type: buddy rows come from the vmemmap, and agree with kl-v2p and kl-pageinfo for the same page -- running all three is a good way to confirm the two bases are right.

Notes¶

No page tables are walked: the direct map is a constant offset, so this works even for a physical address with no valid virtual mapping of its own.

Part of the KernLens tutorial. Every output block on this page was captured from the kernel described in the tutorial index.

kl-p2v¶