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Comment Re:Almost All processors (Score 2) 269

SPARC, MIPS and PowerPC may be fringe but they are still out there in the fringe for servers and/or supercomputers.
Several CPUs of each architecture were released in 2017.

IBM's POWER chips have supported the full PowerPC ISA for a decade and its performance is very competitive to Intel XEON, if not surpassing.

Oracle (which had bought Sun) closed their SPARC processor group last year though. Fujitsu may still be active.

Chinese Loongson makes MIPS processors at 1.5GHz, but they would need to step it up to compete.

I have not checked PowerPC or SPARC but MIPS is not vulnerable to Meltdown. Linux on MIPS can not leak any kernel pages -- simply because MIPS does not do paging in kernel mode.

Comment Re:They did not test AMD or ARM (Score 3, Informative) 269

No, they did test their Meltdown code on AMD and ARM but were not able to reproduce it on the chips they tested on.
That does not prove that a Meltdown-like attack on AMD or ARM is impossible, either on a different chip they did not test on or with a tweaked version of Meltdown.

From the actual article ("meltdown.pdf"):

We also tried to reproduce the Meltdown bug on several ARM and AMD CPUs. However, we did not manage to successfully leak kernel memory with the attack described in Section 5, neither on ARM nor on AMD. The reasons for this can be manifold. First of all, our implementation might simply be too slow and a more optimized version might succeed. For instance, a more shallow out-of-order execution pipeline could tip the race condition towards against the data leakage. Similarly, if the processor lacks certain features, e.g., no re-order buffer, our current implementation might not be able to leak data. However, for both ARM and AMD, the toy example as described in Section 3 works reliably, indicating that out-of-order execution generally occurs and instructions past illegal memory accesses are also performed.

Comment Re:Why develop your own OS? (Score 4, Insightful) 60

There are technical reasons also. Android under the Linux kernel does sandboxing by giving each app its own user, which I find to be a bit of a kludge.

Fuchsia's microkernel Zircon (nee Magenta) instead uses capability-based security, in a model where Processes live in Jobs and Jobs can be nested, allowing the ones that are deeper nested having lesser privileges.
However, Zircon has a major flaw: capabilities can not be revoked, other than by killing the whole process, or jobs.
If I had been in charge, I would have instead chosen seL4, which has revocation, is stable on ARM and which has a formal proof of correctness (was it ten or twenty man-years of work just for the proof? I forget).
But, yeah... seL4 is licensed under GPL. ;-P

Comment Re:MacOS? (Score 1) 416

Yes. I understand it, this Intel flaw concerns the kernel being mapped into all processes' address space at the same addresses. The kernel's memory pages are marked "Global" (present for all processes) and "Ring 0" (Kernel access only). This means that a system call does not require a context switch - only a flip of a bit inside the CPU.
Both Linux, MS Windows and macOS do/did this before the recent patches.

While macOS uses the Mach microkernel which (because it is a microkernel) had been designed to be small(ish) and run alone in Ring 0, Apple has broken the kernel's protection model and put a whole lot of other stuff in global Ring 0 pages as well to increase performance.
This makes their "kernel" almost as large as MS Windows and Linux, providing just as much memory that can be attacked through memory/timing-based attacks.
So, in effect, macOS would be just as vulnerable.

Comment Indifference (Score 2) 200

I'm agnostic until any extra-terrestrial intelligent beings show themselves.

Until then, I believe that some humans could be loons, confused, misguided ... or truthful. But I am not capable to judge, and it would just be a waste of time to delve deep into it, so I leave them alone.

Comment Re:Ghostery and Privacy Badger (Score 3, Informative) 119

I saw "Google Analytics" listed as one of the sites that Firefox delays. I run Privacy Badger in Chromium, so I checked quickly what it blocks on this site and apparently, Slashdot uses Google Analytics but Privacy Badger does not block it.
I suppose that there could be lots of other sites that are let through but which Firefox prioritises down when loading.
This means that running Privacy Badger is not a replacement for the prioritisation scheme that Firefox is doing.

Comment Re:Why 64bit is faster than 32bit? (Score 1) 92

Integer types in C are the same size on 32-bit and 64-bit Windows. On most 64-bit Unix:es and Linux, "long int" are 64 bits as opposed to 32 bits.

The big difference is that pointers are 64 bits instead of 32.
Pointers and 64-bit integers are also 8-byte aligned instead of 4-byte aligned. (at least on Linux they are)
It may not seem much but if you have large arrays of structs with these types, it could add up.


Bitcoin's Value Plummeted Overnight and No One Knows Why ( 461

Jacob Brogan, writing for Slate: While the Western Hemisphere slept, Bitcoin plummeted. Just after midnight Eastern Time on Friday, the cryptocurrency was valued at a little over $15,000, on the digital currency exchange Coinbase. At that point, it was already well below the $19,783 all-time high it had hit the week before. Over the course of the night, Bitcoin began to decline erratically, occasionally spiking but following a general downward trend. Around 9:22 a.m. Eastern, it hit a temporary floor, valued at a mere $10,400. By that point, it had declined more than $6,000 from its short-term peak the morning before, having lost more than one-third of its value. Bitcoin wasn't the only currency hit by a sharp drop. Tech Crunch's Jon Russell reports that most other prominent cryptocurrencies also fell, including Ethereum, Litecoin, and Bitcoin Cash (which is, confusingly, separate from Bitcoin proper). As Russell notes, it's hard to say why this is happening, "in the same way that nobody knows exactly why bitcoin's price has [shot] up from a touch under $1,000 at the start of the year."

Comment Re: No radiation risk (Score 1) 344

Meanwhile, in my small country, brain tumours are on the rise. Cell phones seem to be more popular here than in the US. The cities are more densely populated.

Anyway, I don't think the risk is so much from cell phones themselves.
I would be more concerned for people who are living or working too close to a cell phone tower. In the latter case, it is not just the frequency band that the cell phone is using, when it is being used. That tower is on all the time and could be in 2G, 3G, 4G and 5G all at once and/or long-range high-speed directional microwave links between towers instead of fibre.

Comment Re:No radiation risk (Score 1) 344

That's not how it works.

The electromagnetic waves from mobile phones do not cause the initial mutation that causes a cell to turn into a cancer cell and multiply out of control. That fact has been long established and is not contested here.
What microwaves in the frequency ranges used by cell phones have been shown to do is to promote the growth of existing cancel cells.

Mutations into cancer cells are actually not as uncommon as most people think. All of us have had cancer cells many many times, but what normally happens is that the immune system detects the microtumour and kills it long before it has grown large enough to cause a serious problem.
All of us have been exposed to cosmic radiation, practically all of us have had X-rays a few times in our lives, all of us have inhaled and ingested carcinogenic chemicals from car exhaust, pollution, first- or second-hand tobacco smoke etc. etc.

Carcinogens are all around us, but you don't get cancer that easily.
Cancer risk is about probabilities: many different factors are at play.
And radio frequencies in the part of the microwave spectrum, at frequencies and levels that mobile phones use - have been proven in several studies (I have heard of two beside the California study) to be one of those factors.

Comment Re:Ad (Score 1) 269

I agree. Mara Jade even had an official model that used to show up at sci-fi conventions, as did many of the book authors.
The problem with the EU is that were quite a few things in the EU that was of questionable quality, and many things even contradicted each other or contradicted facts in the prequel movies.

At a convention in summer of 2013, Lucasfilm announced that they were going to sort the EU out. They were going to pick the best bits and put the main storyline into a new consistent canon and scrap the rest. (I was there in person and heard it directly from Leland Chee's and Pablo Hidalgo's lips)
In early 2014, however ... Lucasfilm announced that they were instead going to scrap it all and relabel it as "Legends". They still print and sell new copies of those books though - with a new "Legends" label on the cover.

Dave Filoni (showrunner of Clone Wars and Rebels) did pick a lot out from the old EU to use in his series. Grand Admiral Thrawn in Rebels is one of those. The Nightsisters of Dathomir is from the EU also.
Darth Maul's comeback with robotic legs is not even from the EU, but from an alternate universe story where he shows up on Tatooine, wanting revenge on Obi-Wan for having been cut in half on Naboo some thirty years earlier ...

Comment Re:In this thread (Score 1) 269

The two main complains I have seen about The Last Jedi have been:

* It contained too much comedy. It reminded them too much of a Saturday morning cartoon than a Star Wars flick.
That's perfectly fine for a movie -- if that is the general tone of the franchise but this is the eight movie in a series and that would in many older viewers' eyes require it to follow an established format or it would get close to jumping the shark.
For the casual viewer, however, and for most reviewers -- who don't view the movie more deeply in context -- this does not matter at all.

* At the end, not much has been accomplished. The state of the universe is pretty much as it was when the movie started.
I don't agree with that though.

* It is too long and could have been shortened. This movie is two and a half hours where as every other Star Wars has been around two hours.

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