I missed one method write protect Bits in the CSD register of the sdcard.
This is also not a suggestion. The permanent write protect option burns the epproms fuseable link that allows writing clean out. Once done there is no reverse.
The switch is a suggestion or phsycal depending on the card. The CSD register if not set temp but permanent read only is a one way operation that can never be reversed. You need to change the bootloader dump the card start with another card if CSD register has been used since it will never allow changig.
This is the reality the level of brute force required is slightly different between all chromebooks. You prefer to have one with a controler that works or a SD with a working write protect switch. But all else fails blow te fuseable links and this will be write protected in every SD taking device forever more.
This is knowning the hardware. SD card can alway be set read only. SD card cannot always be set read write. Combine that with the fixed boot order of most chromebooks you have have to secure them.
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Re: Lot of chromebooks could be secured.
Date: 2013-02-05 08:03 am (UTC)This is also not a suggestion. The permanent write protect option burns the epproms fuseable link that allows writing clean out. Once done there is no reverse.
The switch is a suggestion or phsycal depending on the card. The CSD register if not set temp but permanent read only is a one way operation that can never be reversed. You need to change the bootloader dump the card start with another card if CSD register has been used since it will never allow changig.
This is the reality the level of brute force required is slightly different between all chromebooks. You prefer to have one with a controler that works or a SD with a working write protect switch. But all else fails blow te fuseable links and this will be write protected in every SD taking device forever more.
This is knowning the hardware. SD card can alway be set read only. SD card cannot always be set read write. Combine that with the fixed boot order of most chromebooks you have have to secure them.
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