CONFIG_BFIN_L2_WRITEBACK is not available for thedefaultarchitecture x86.
Result is shown for architecture blackfin
default or selected kernelversion does not have config value CONFIG_BFIN_L2_WRITEBACK.
Result is shown for kernelversion 6.7-rc3

Write back

configname: CONFIG_BFIN_L2_WRITEBACK

L2 SRAM DCACHE policy
└─>Write back
In linux kernel since version 2.6.31 (release Date: 2009-09-09)