下面这段内核配置文件对照你的有什么不同吗?
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[ * ] Support for console on virtual terminal
< * > Standard/generic (8250/16550 and compatible UARTs) serial support
[ ] Support for console on serial port
[ ] Extended dumb serial driver options
[ ] Non-standard serial port support
[ * ] Unix98 PTY support
(256) Maximum number of Unix98 PTYs in use (0-2048)
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