[PATCH net-next 1/2] netlink: specs: nlctrl: fix the policy attribute numbering

[Jakub Kicinski <kuba@kernel.org>]

mask and pad are declared the wrong way round, giving mask 11 and
pad 12, while enum netlink_policy_type_attr has
NL_POLICY_TYPE_ATTR_PAD at 11 and NL_POLICY_TYPE_ATTR_MASK at 12.

The kernel emits the mask for every NLA_POLICY_MASK() attribute, so a
Python YNL client parsing a policy dump maps it onto pad and throws it
away - 30 of them in ethtool's policy alone.  In the other direction the
64-bit alignment padding, which the kernel does emit on architectures
without efficient unaligned access, is decoded as a u64 mask and blows
up the whole dump. But those architectures are rare.

The generated C parser is not affected, it keys the attributes off the
uAPI symbol names rather than off the values the spec derives.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 Documentation/netlink/specs/nlctrl.yaml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Documentation/netlink/specs/nlctrl.yaml b/Documentation/netlink/specs/nlctrl.yaml
index 7e7c158e3e73..6acac4aeab03 100644
--- a/Documentation/netlink/specs/nlctrl.yaml
+++ b/Documentation/netlink/specs/nlctrl.yaml
@@ -156,12 +156,12 @@ doc: |
       -
         name: bitfield32-mask
         type: u32
-      -
-        name: mask
-        type: u64
       -
         name: pad
         type: pad
+      -
+        name: mask
+        type: u64
       -
         name: byte-order
         doc: Byte order of the attribute, absent means host byte order.
-- 
2.55.0