CONFIG_LOG_BUF_SHIFT 615 drivers/tty/serial/fsl_linflexuart.c if (earlycon_buf.len >= 1 << CONFIG_LOG_BUF_SHIFT) CONFIG_LOG_BUF_SHIFT 457 kernel/printk/printk.c #define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT)