The google memconsole driver is currently broken upstream, as it tries
to read memory that is described as reserved in /proc/iomem, by
dereferencing a pointer obtained through phys_to_virt(). This triggers
a kernel fault as such regions are unmapped after early boot.
The proper workaround is to use ioremap_cache() / iounmap() around such
accesses.
As some unrelated changes, I also converted some printks to use pr_info()
and added some missing __init annotations.
Tested: booted dbg build, verified I could read /sys/firmware/log
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch introduces the 'memconsole' driver.
Our firmware gives us access to an in-memory log of the firmware's
output. This gives us visibility in a data-center of headless machines
as to what the firmware is doing.
The memory console is found by the driver by finding a header block in
the EBDA. The buffer is then copied out, and is exported to userland in
the file /sys/firmware/log.
Signed-off-by: San Mehat <san@google.com>
Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>