powerpc/pkeys: Fix reading of ibm, processor-storage-keys property
scan_pkey_feature() uses of_property_read_u32_array() to read the ibm,processor-storage-keys property and calls be32_to_cpu() on the value it gets. The problem is that of_property_read_u32_array() already returns the value converted to the CPU byte order. The value of pkeys_total ends up more or less sane because there's a min() call in pkey_initialize() which reduces pkeys_total to 32. So in practice the kernel ignores the fact that the hypervisor reserved one key for itself (the device tree advertises 31 keys in my test VM). This is wrong, but the effect in practice is that when a process tries to allocate the 32nd key, it gets an -EINVAL error instead of -ENOSPC which would indicate that there aren't any keys available Fixes: cf43d3b2 ("powerpc: Enable pkey subsystem") Cc: stable@vger.kernel.org # v4.16+ Signed-off-by: NThiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
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