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8a3e3d31d1
With CONFIG_STRICT_DEVMEM=y, user space cannot read any part of /dev/mem.
Since this breaks librtas, punch a hole in /dev/mem to allow access to the
rmo_buffer that librtas needs.
Anton Blanchard reported the problem and helped with the fix.
A quick test for this patch:
# cat /proc/rtas/rmo_buffer
000000000f190000 10000
# python -c "print 0x000000000f190000 / 0x10000"
3865
# dd if=/dev/mem of=/tmp/foo count=1 bs=64k skip=3865
1+0 records in
1+0 records out
65536 bytes (66 kB) copied, 0.000205235 s, 319 MB/s
# dd if=/dev/mem of=/tmp/foo
dd: reading `/dev/mem': Operation not permitted
0+0 records in
0+0 records out
0 bytes (0 B) copied, 0.00022519 s, 0.0 kB/s
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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| boot | ||
| configs | ||
| include/asm | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| platforms | ||
| sysdev | ||
| xmon | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| relocs_check.pl | ||