From: Dave Jones <davej@redhat.com>
To: linux-acpi@vger.kernel.org
Subject: systemd, fpdt and /dev/mem
Date: Mon, 10 Nov 2014 16:21:42 -0500 [thread overview]
Message-ID: <20141110212142.GA2337@redhat.com> (raw)
I just noticed systemd has started doing this:
[ 3228.978745] Program systemd tried to access /dev/mem between 30a48000->30a48008.
After some investigation, it seems that it's reading
/sys/firmware/acpi/tables/FPDT to get a pointer, and then trying to read
that address using /dev/mem. Asides from the grossness of grovelling around in
memory, given it's too late to stop exporting pointers in sysfs objects,
should there perhaps be a better way to export the data the FPDT is
pointing at ?
Or should some part of acpi be reserving the memory range it points to,
so that the /dev/mem driver doesn't freak out ?
Curiously, the address it points to is in this range..
302b5000-3129dfff : Kernel bss
Which makes me wonder what exactly it's reading.
Dave
reply other threads:[~2014-11-10 21:21 UTC|newest]
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