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A comment on The status of Linux kernel hardening. Parent comment

Re:The status of Linux kernel hardening by _pmf_ on Thursday November 10, 2016 @04:32AM (#12918965)
> This is so true. Back in the day when I was involve in embedded Linux development, the quickest bootup time was about 40secs. This was booting a v2.6 kernel in a minimum configuration on an ARM7 system over SPI NAND FLASH.

The older NAND file systems were very slow. I've had a similar case where repartitioning the huge NAND into a smaller partition and only using a small partition reduced the boot time to 10 seconds without any other change. Modern UBIFS systems apparently don't have this problem.

As for subsecond boot times: no chance with Linux.

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Re:The status of Linux kernel hardening by rkeene2 on Thursday November 10, 2016 @12:13PM (#12922181)
I've booted Linux in sub-second times using User Mode Linux so there's nothing actually preventing it other than the need to probe hardware in various slow ways, which could be improved.
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Re:The status of Linux kernel hardening by yitchelle on Thursday November 10, 2016 @04:08PM (#12924355)
So this is going from connecting power to having a full system ready to go?
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Re:The status of Linux kernel hardening by rkeene2 on Tuesday November 15, 2016 @12:57PM (#12960395)
The question doesn't really make sense since there's no "power" involved -- the kernel neither has nor lacks power... but if I understand the nature of the question, then the answer is "yes" -- the system goes from not existing to being at a bash prompt in under 0.3s on my laptop.
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Re:The status of Linux kernel hardening by yitchelle on Thursday November 10, 2016 @05:16AM (#12919174)
Just looked up what UBIFS is, and saw the reference to JFFS2. We tried JFFS, it was painfully slow. JFFS2 was emerging and tried that too. In reality, it did not really worked for booting up. Once it was up, it was pretty good. Unfortunately, we were developing a hand hand consumer electronics device, so boot up times were absolutely critical.
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