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>> + return le64_to_cpu(READ_ONCE(*rs->read_index_ptr)); >> +} >> + >> +static void sdxi_ring_state_store_widx(struct sdxi_ring_state *rs, u64 new_widx) >> +{ >> + lockdep_assert_held(&rs->lock); >> + *rs->write_index_ptr = cpu_to_le64(rs->write_index = new_widx); > > Does it need WRITE_ONCE() ? you load_ridx() use READ_ONCE. I just not sure > > suppose doorbell will drain write buffer, most likely it is okay without > WRITE_ONCE() The SDXI implementation is free to sample the write index before software hits the doorbell, so I believe WRITE_ONCE() is required here, thanks.