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From: Mikolaj Golub <trociny@freebsd.org>
To: freebsd-hackers@freebsd.org
Sender: Mikolaj Golub <to.my.trociny@gmail.com>
Date: Sun, 16 Oct 2011 19:57:57 +0300
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Cc: Kostik Belousov <kib@FreeBSD.org>, Robert Watson <rwatson@freebsd.org>
Subject: "ps -e" without procfs(5)
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Hi,

I have a patch that makes kvm_uread() read from user space using ptrace(2).

http://people.freebsd.org/~trociny/kvm_uread.ptrace.patch

With this change 'ps -e' does not requires procfs(5).

Do you like it or there might be some reasons why it is a bad idea?

Grepping sources it looks like currently only ps uses kvm_getenvv(3) (and thus
kvm_uread()).

Note, when reading from its own user space it just does bcopy(3), so if a
wrong address range is passed to kvm_uread() the program will segfault. Do we
need some protection here and what? Masking SIGSEGV?

-- 
Mikolaj Golub