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Any change to a serialized > > structure, even an optional additive one, must bump the string, which > > breaks live update between adjacent kernels. Replace the string in > > struct luo_ser with a feature header, so that the target kernel can > > accept or reject the source kernel state per feature. > > > > struct luo_feature_hdr is a fixed 128-byte header: the serialized > > This patch is all wrong; 128 bytes is far too large. For every _ser > struct, we only need 8 bytes instead. > > The first 4 bytes are the size, and the next 4 bytes are flags (i.e., > 30 feature flags + 2 reserved bits for flags extension). The last two > bits of the flags indicate whether an extended flags field is present. > Each extended flags field is 8 bytes, and its last two bits indicate > that yet another extended flags field follows. I thought we agreed not to loose the string too, it was a tree string -> feature flags -> individual values The string is the emergency if we really badly mess it up. Jason