金枪鱼之夜：支持多种 ISA 扩展的二进制背后的秘密
随着算力需求的提升，我们不断往 CPU 加入新的 ISA 扩展来提高指令表达能力。然而，在软件分发过程中，为每一种 CPU 所支持的 ISA 扩展组合进行编译与分发并不现实，无法接受各种组合的软件构建成本以及镜像站的存储成本。因此，在目前的软件中，往往通过增加性能敏感函数针对不同 ISA 的实现，配合一些函数重定向方法来解决问题。然而，这些方法或多或少存在性能或安全的问题，特别是 IFUNC 机制更是被著名的 xz 软件后门所利用。因此，cyy 希望在 Tunight 上与大家分享目前常见软件实现一个二进制支持多种 ISA 扩展的方法，以及探讨目前的性能与安全问题的案例以及可行的解决方案。
- 主讲人：陈泱宇
- 时间：2024/06/08（校历第十五周周六） 19:00-21:00 UTC +08:00
- 活动形式：线下 + 线上会议 + 直播
- 地点：三教 3104
- 线上会议：Zoom 会议: 970 8479 0044, 密码 20240608
- 直播链接：YouTube 直播: https://youtube.com/live/s78ynPBsTtY
随着算力需求的提升，我们不断往 CPU 加入新的 ISA 扩展来提高指令表达能力。然而，在软件分发过程中，为每一种 CPU 所支持的 ISA 扩展组合进行编译与分发并不现实，无法接受各种组合的软件构建成本以及镜像站的存储成本。因此，在目前的软件中，往往通过增加性能敏感函数针对不同 ISA 的实现，配合一些函数重定向方法来解决问题。然而，这些方法或多或少存在性能或安全的问题，特别是 IFUNC 机制更是被著名的 xz 软件后门所利用。因此，cyy 希望在 Tunight 上与大家分享目前常见软件实现一个二进制支持多种 ISA 扩展的方法，以及探讨目前的性能与安全问题的案例以及可行的解决方案。
- 主讲人：陈泱宇
- 时间：2024/06/08（校历第十五周周六） 19:00-21:00 UTC +08:00
- 活动形式：线下 + 线上会议 + 直播
- 地点：三教 3104
- 线上会议：Zoom 会议: 970 8479 0044, 密码 20240608
- 直播链接：YouTube 直播: https://youtube.com/live/s78ynPBsTtY
#今日看了什么
#NetBoot
原来从 GRUB 启动 ISO 这么简易
https://netboot.xyz/docs/booting/grub
#NetBoot
原来从 GRUB 启动 ISO 这么简易
# Install grub-imageboot
apt install grub-imageboot
# Download netboot.xyz ISO
mkdir /boot/images
cd /boot/images
wget https://boot.netboot.xyz/ipxe/netboot.xyz.iso
# Update GRUB menu to include this ISO
update-grub2
reboot
https://netboot.xyz/docs/booting/grub
netboot.xyz
Booting from an existing Linux installation using GRUB | netboot.xyz
How to use GRUB to boot into netboot.xyz
Chips and Cheese
Update on Meteor Lake DRAM Latency Measurements
#ChipAndCheese
Telegraph | source
(author: clamchowder)
Update on Meteor Lake DRAM Latency Measurements
#ChipAndCheese
Telegraph | source
(author: clamchowder)
Daniel Lemire's blog
Science and Technology links (May 25 2024)
1. Artificial intelligence is far more efficient at producing content than human beings, as far as carbon emissions go.
2. Human brains got larger by over 5% between 1930 and 1970.
3. Replacing plastics by ‘environment friendly’ alternatives typically results in greater greenhouse gas emissions.
4. Prostate-specific antigen screening has only a small effect on men’s risk of dying in absolute terms.
5. Local exposure to poor individuals reduces support for redistribution among the well-off. In other words, wealthy people are more likely to favor government programs helping the poor if they never see poor people.
6. Happier looking people are judged better. If you want to be viewed as a good person, make sure you appear happy.
7. Females mount stronger immune responses to many pathogens, they awaken more frequently at night, they express greater concern about physically dangerous stimuli, they exert more effort to avoid social conflicts, they exhibit a personality style more focused on life’s dangers, they react to threats with greater fear, disgust and sadness and they develop more threat-based clinical conditions than males. (Benenson et al.).
8. The Lincoln sea, the sea North of Greenland, was ice free about 10,000 years ago.
9. ADHD and autism referrals up fivefold in 2023 in the UK. It is unclear why that is, but over diagnosis is a possibility.
10. We believe that one of the earliest city might have been in modern-day Turkey, about 9,000 years ago.
11. About 20,000 years ago, sea levels were over 100 meters lower, as we were in the last glacial maximum.
12. High-intensity strength training exercises are an effective means to preserve bone density while improving muscle mass, strength, and balance in postmenopausal women.
13. The average American is willing to pay over 500$ to get a 3-month exemption from a medical mask mandate.
14. Experiencing nature leads to healthier food choices.
15. Australia is getting greener, rapidly.
16. When you lose weight, you spend less energy. However, if you consume relatively more fat or protein during the weight loss, you tend to use more energy.
17. Trees are getting bigger.
18. Sun exposure may improve your health.
19. They are conducting a clinical trial for tooth regrowth technology in Japan.
source
Science and Technology links (May 25 2024)
1. Artificial intelligence is far more efficient at producing content than human beings, as far as carbon emissions go.
2. Human brains got larger by over 5% between 1930 and 1970.
3. Replacing plastics by ‘environment friendly’ alternatives typically results in greater greenhouse gas emissions.
4. Prostate-specific antigen screening has only a small effect on men’s risk of dying in absolute terms.
5. Local exposure to poor individuals reduces support for redistribution among the well-off. In other words, wealthy people are more likely to favor government programs helping the poor if they never see poor people.
6. Happier looking people are judged better. If you want to be viewed as a good person, make sure you appear happy.
7. Females mount stronger immune responses to many pathogens, they awaken more frequently at night, they express greater concern about physically dangerous stimuli, they exert more effort to avoid social conflicts, they exhibit a personality style more focused on life’s dangers, they react to threats with greater fear, disgust and sadness and they develop more threat-based clinical conditions than males. (Benenson et al.).
8. The Lincoln sea, the sea North of Greenland, was ice free about 10,000 years ago.
9. ADHD and autism referrals up fivefold in 2023 in the UK. It is unclear why that is, but over diagnosis is a possibility.
10. We believe that one of the earliest city might have been in modern-day Turkey, about 9,000 years ago.
11. About 20,000 years ago, sea levels were over 100 meters lower, as we were in the last glacial maximum.
12. High-intensity strength training exercises are an effective means to preserve bone density while improving muscle mass, strength, and balance in postmenopausal women.
13. The average American is willing to pay over 500$ to get a 3-month exemption from a medical mask mandate.
14. Experiencing nature leads to healthier food choices.
15. Australia is getting greener, rapidly.
16. When you lose weight, you spend less energy. However, if you consume relatively more fat or protein during the weight loss, you tend to use more energy.
17. Trees are getting bigger.
18. Sun exposure may improve your health.
19. They are conducting a clinical trial for tooth regrowth technology in Japan.
source
已领取学士服🥰
