Re: [PATCH] powerpc/papr_scm: Make access mode of 'perf_stats' attribute file to '0400'

The newly introduced 'perf_stats' attribute uses the default access mode of 0444 letting non-root users access performance stats of an nvdimm and potentially force the kernel into issuing large number of expensive HCALLs. Since the information exposed by this attribute cannot be cached hence its better to ward of access to this attribute from non-root users. Hence this patch updates the access-mode of 'perf_stats' sysfs attribute file to 0400 to make it only readable to root-users.

Reported-by: Aneesh Kumar K.V <aneesh.kumar(a)linux.ibm.com&gt; Signed-off-by: Vaibhav Jain <vaibhav(a)linux.ibm.com&gt;