social.kernel.org

Harry (Hyeonggon) Yoo

@hyeyoo

Posts

492

Following

97

Followers

112

A relatively new professional kernel hacker, born in August 6, 2000, and living in Korea (South!).

- Linux Kernel Developer @ Oracle (Linux Kernel MM) (2025.02 ~ Present)
- Reviewer for the Linux Slab & Reverse Mapping subsystem
- Former Intern @ NVIDIA, SK Hynix, Panmnesia (Security, MM and CXL)
- B.Sc. in Computer Science & Engineering, Chungnam National University (Class of 2025)

Opinions are my own.

My interests are:
Memory Management,
Computer Architecture,
Circuit Design,
Virtualization

Harry (Hyeonggon) Yoo

hyeyoo

Edited 2 years ago

I was unable to access my school's e-learning site this morning. Turns out I was expelled from school for unknown reason. I was panicking, but a school employee called me to say that there was a mistake while processing scholarship for school tuition and everything will be fine.

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Harry (Hyeonggon) Yoo

hyeyoo

off and off

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Harry (Hyeonggon) Yoo

hyeyoo

@ljs @cwayne @vbabka
Don't forget to mention me when discussing
g dumb idiots

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Harry (Hyeonggon) Yoo

hyeyoo

Reply to

@kernellogger @ljs

lol there are already so many obstacles in this driver's way

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Harry (Hyeonggon) Yoo

hyeyoo

Reply to

@kernellogger @ljs

I use KVM only for kernel development and virtualbox/vmware for other work.

Because I'm not familiar with KVM yet,
maybe this is the chance to completely migrate to KVM ;)

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Harry (Hyeonggon) Yoo

hyeyoo

Edited 2 years ago

looks like @ljs 's changes to GUP broke my out-of-tree virtualbox driver. out-of-tree drivers suck :P

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Harry (Hyeonggon) Yoo

hyeyoo

Edited 2 years ago

@ljs @ptesarik Yes! "might be the case" was was not clear ;)

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Harry (Hyeonggon) Yoo

hyeyoo

Reply to @hyeyoo

Edited 2 years ago

@ptesarik @ljs

I thought maybe freeing unnecessary vmemmap pages for HugeTLB pages might be the case, but it seems to remap to first vmemmap page. And if I am not mistaken pfn_valid() will return true for them.

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Harry (Hyeonggon) Yoo

hyeyoo

Starting to like Joan's drawings more

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Harry (Hyeonggon) Yoo

hyeyoo

TIL: NUMA configuration and distance matrix are parsed from device trees, ACPI, or dummy configuration is used.

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Harry (Hyeonggon) Yoo

hyeyoo

Edited 2 years ago

Videos of LSFMMBPF Summit / OSSNA sessions are now available on Youtube:

https://youtube.com/playlist?list=PLbzoR-pLrL6rlmdpJ3-oMgU_zxc1wAhjS

https://youtube.com/playlist?list=PLbzoR-pLrL6p445pIqTLUIzsceFp_puSy

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Harry (Hyeonggon) Yoo

hyeyoo

Reply to

@ptesarik @ljs

When do usable PFNs (for which pfn_valid() is false) exist?

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Harry (Hyeonggon) Yoo

hyeyoo

Reply to @vbabka

LMAO probably should launch more like the north one?
(...learning how to make a joke...)

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Harry (Hyeonggon) Yoo

hyeyoo

South Korea's space rocket Nuri launched

https://en.yna.co.kr/view/AEN20230524009656320

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Harry (Hyeonggon) Yoo

hyeyoo

@ljs @vbabka Can't even imagine what it was like before CoC was introduced.

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Harry (Hyeonggon) Yoo

hyeyoo

Edited 2 years ago

@ljs when does it matter? the only thing I know about it is that the kernel does not have struct page when pfn_valid() is false.

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Harry (Hyeonggon) Yoo

hyeyoo

Edited 2 years ago

@ljs Feeling much better to hear that, thank you! I need to be stronger ;)

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Harry (Hyeonggon) Yoo

hyeyoo

Edited 2 years ago

seems I made a mistake,
want to be more wise and strong!

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Harry (Hyeonggon) Yoo

hyeyoo

Edited 2 years ago

@ljs My mind, thoughts, and process of reasoning are easily broken too :)

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Harry (Hyeonggon) Yoo

repeated

vbabka

SLAB deprecation posted! So many defconfigs...
https://lore.kernel.org/all/20230523091139.21449-1-vbabka@suse.cz/

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