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What a beautiful story! I've read a similarly impressive account, where a GNU/Linux system was revived in comparably wizard-like manner, with Kernel hacker Al V
by c0l0 6y ago
What a beautiful story! I've read a similarly impressive account, where a GNU/Linux system was revived in comparably wizard-like manner, with Kernel hacker Al Viro involved: https://yarchive.net/comp/linux/extreme_system_recovery.html https://yarchive.net/comp/linux/extreme_system_recovery.html
It was linked to in an LWN article's comment section, titled "If you think you're really good, read this.", or something. The story proved very effective at humbling its reader for me.
That doesn't change the fact that I, too, once felt like the uncrowned teenage king of emergency system rescue operations back in 2002 or so, right in my parents' basement. I had started recursively deleting / by accident, and ended up with most directories, /bin and /sbin included, already turned to dust, and most of my as of then proudest achievement - a Gentoo Linux stage 1 installation - gone.
I dug myself (and the standing remains of my /home) out of that particular hole by virtue of still having an instance of a browser (I think firefox) running. Mildly panicking, I still left everything untouched ... and after a few hours of thinking hard about what to do, I arrived at the following: I set up a webserver on my mom's windows PC with am embedded PHP interpreter, and hacked up a script that enabled file uploads via HTTP over the LAN. After using that from within my still-running browser (fortunately, it could still list the contents of my home directory) to evac the most precious artifacts my ~ had in store, I rebooted my machine into the lightless nothingness of not having a kernel image in /boot any more. Another few hours later, I had Gentoo reinstalled, and copied the rescued files over to my own machine again - and felt like I had levelled up a little bit.
- segfaultbuserr 6y ago> comparably wizard-like manner, with Kernel hacker Al Viro involved: https://yarchive.net/comp/linux/extreme_system_recovery.html https://yarchive.net/comp/linux/extreme_system_recovery.html If I were him, the best I could imagine was doing documentation reading and ASM writing on a separate computer with working toolchains, testing it, and finally entering some machine code in hex to the broken machine by hand. But he literally wrote an ASM program and constructed an ELF on a totally broken machine itself on the fly, with no documentation, no toolchain. Absolutely wizard. For example, it was how the syscall number was found without grep... > The next step was getting the syscall numbers. grep? We don't need no stinkin' grep. # while read i; do case $i in *__NR_link*) echo $i;; esac; done </usr/include/asm/unistd.h #define __NR_link 9 # while read i; do case $i in *__NR_exit*) echo $i;; esac; done </usr/include/asm/unistd.h #define __NR_exit 1 #define __NR__exit __NR_exit