I've been asked to implement bubblesort, by a processor design team, in verilog. I haven't done bubblesort since HS while learning examples of slow sorts.
I passed the interview, not because I had memorized this algorithm (which is certainly irrelevant to my career and the job I was applying for), because I reinvented bubblesort on the fly in pseudocode. The interviewer was willing to entertain my speculation about what bubblesort meant, he just wanted to watch me flail around.
I'm fairly certain he couldn't care less about bubblesort, he wanted to give me a problem and watch me solve it, what kind of questions I asked and what mistakes I made. Then he wanted to critique my solution and see how I handled his critique.
It's very hard to interview technical people, different people have different philosophies. Plenty of people will point to the exhaustive list of experience on their resume, which is meaningless since you can spend a lot of years doing absolutely nothing. Others will point to their degrees, which is meaningless since even a degree from an accredited university only means you took some required courses and the professor gave you a passing grade. Fundamentally we are there to solve problems though, so you should be trying to find a way to gauge problem solving.
My objections to bubblesort is that it's a well defined algorithm and people may get stuck on implementing it in some canonical way. Reversing a linked list is a better question, if you're going to go that route (although well trod and certainly H1B prep schools teach it by now). The question should take common knowledge from your field and basic problem solving. You should not be asking problems that require real brainpower, the interviewee is nervous and under-pressure in bad ways and not likely going to respond optimally.
The real problem with these tough interviews is that mostly they're being used to justify the lack of qualified people in the country. Turn down enough natives and HR starts suppling well coached shills from abroad, who once you get them turn out not to be very good, but knew quite well what they were to be asked.