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Date: Fri, 16 Apr 2010 10:17:15 +0400 (MSD)
From: malc <av1474@comtv.ru>
Subject: Re: [Qemu-devel] Which functions writes to memory?
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To: Jun Koi <junkoi2004@gmail.com>
Cc: qemu-devel@nongnu.org

On Fri, 16 Apr 2010, Jun Koi wrote:

> Hi,
> 
> I am writing a small tool to trace all the activities that write to an
> area of (virtual) memory in Qemu.
> I am currently doing that by putting my code at the top of the below
> macro in softmmu_header.h
> 
> static inline void glue(glue(st, SUFFIX), MEMSUFFIX)....
> 
> However, it seems I still miss some written events: in some occasions,
> I believe that Qemu has another code writing data to memory, which
> happens even before this macro.
> Is it true that elsewhere, Qemu also writes into memory besides using
> above function?
> 
> The memory area I am tracking for written events belong to normal area
> in OS kernel, where usually only normal code (kernel, not something
> like SMM handler)  write to.

Once the TLB is properly set up st helpers are bypassed entirely and
tcg generated code writes to it directly, it's quite easy to "workaround"
that at the expense of much slower execution.

-- 
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