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From: Peter Maydell <peter.maydell@linaro.org>
Date: Wed, 29 Oct 2014 17:56:59 +0000
Message-ID: <CAFEAcA9JNVsT57Zgy96+cfdWBABE4_g4yJG7Te8Oa8ReXZqeRQ@mail.gmail.com>
Subject: Re: [Qemu-devel] [PATCH 00/17] RFC: userfault v2
To: Andrea Arcangeli <aarcange@redhat.com>
Cc: zhanghailiang <zhang.zhanghailiang@huawei.com>,
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On 29 October 2014 17:46, Andrea Arcangeli <aarcange@redhat.com> wrote:
> After some chat during the KVMForum I've been already thinking it
> could be beneficial for some usage to give userland the information
> about the fault being read or write

...I wonder if that would let us replace the current nasty
mess we use in linux-user to detect read vs write faults
(which uses a bunch of architecture-specific hacks including
in some cases "look at the insn that triggered this SEGV and
decode it to see if it was a load or a store"; see the
various cpu_signal_handler() implementations in user-exec.c).

-- PMM
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