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A comment on A bootable CD image with a retro game in a single tweet. Parent comment

Re:A bootable CD image with a retro game in a single tweet by saagarjha on Tuesday July 31, 2018 @06:03PM (#17657658)
> what we have now

x86 processors still boot into real mode…

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Re:A bootable CD image with a retro game in a single tweet by yjftsjthsd-h on Tuesday July 31, 2018 @06:40PM (#17657926)
It's my understanding that UEFI actually comes up directly into long mode?

"UEFI firmware performs those same steps, but also prepares a protected mode environment with flat segmentation and for x86-64 CPUs, a long mode environment with identity-mapped paging. The A20 gate is enabled as well."

- https://wiki.osdev.org/UEFI

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Re:A bootable CD image with a retro game in a single tweet by dlubarov on Tuesday July 31, 2018 @11:38PM (#17659456)
Unfortunately most BIOS services are only available in real mode, so it's often necessary to switch back and forth.
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Re:A bootable CD image with a retro game in a single tweet by basementcat on Tuesday July 31, 2018 @07:54PM (#17658402)
This inadvertently triggered my A20 gate rage.
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