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Date: Thu, 3 Apr 2025 13:15:46 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Kees Cook <kees@kernel.org>, linux-kernel@vger.kernel.org,
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 <mathieu.desnoyers@efficios.com>, Andrew Morton
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 Vlastimil Babka <vbabka@suse.cz>, Mike Rapoport <rppt@kernel.org>, Tony
 Luck <tony.luck@intel.com>, "Guilherme G. Piccoli" <gpiccoli@igalia.com>,
 linux-hardening@vger.kernel.org
Subject: Re: [PATCH v2 1/2] tracing: ring-buffer: Have the ring buffer code
 do the vmap of physical memory
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On Thu, 3 Apr 2025 09:51:51 -0700
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> I *suspect* the history is simply that 'vmap()' predates 'vmap_page_range()'.
> 

Doing some git archeology, it appears vmap_page_range() was added last
year, to replace some ioremap_page_range() use cases, by Alexei.

In 2021, Christoph moved ioremap_page_range() to vmalloc.c replacing
vmap_range().

Also in 2021, Nick changed the ioremap_*range to vmap_*_range(), basically
making this full circle.

The ioremap_page_range() was introduced in 2006.

vmap() looks to have been there before you started git.

The vmap() usage in pstore was introduced in 2012.

-- Steve