hwmon: (
f71805f) Use request_muxed_region for Super-IO accesses
Super-IO accesses may fail on a system with no or unmapped LPC bus.
Unable to handle kernel paging request at virtual address
ffffffbffee0002e
pgd =
ffffffc1d68d4000
[
ffffffbffee0002e] *pgd=
0000000000000000, *pud=
0000000000000000
Internal error: Oops:
94000046 [#1] PREEMPT SMP
Modules linked in:
f71805f(+) hwmon
CPU: 3 PID: 1659 Comm: insmod Not tainted 4.5.0+ #88
Hardware name: linux,dummy-virt (DT)
task:
ffffffc1f6665400 ti:
ffffffc1d6418000 task.ti:
ffffffc1d6418000
PC is at f71805f_find+0x6c/0x358 [
f71805f]
Also, other drivers may attempt to access the LPC bus at the same time,
resulting in undefined behavior.
Use request_muxed_region() to ensure that IO access on the requested
address space is supported, and to ensure that access by multiple
drivers is synchronized.
Fixes: e53004e20a58e ("hwmon: New f71805f driver")
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: John Garry <john.garry@huawei.com>
Cc: John Garry <john.garry@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>