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Comment: Re: Lazy farmer (Score 2) 88

by Rei (#48671173) Attached to: Scientists Say the Future Looks Bleak For Our Bones

But it does raise a serious issue - they're studying changes that don't necessarily reflect the selective pressures of present-day life.

Think about it: what are the leading causes of death for people in the prime breeding age (15-34)? Car accidents - by a good margin. So isn't this significant selective pressure to beef up the neck against whiplash, the skull against forehead impact, survival during significant blood loss, etc?

#2 is suicide. I don't know how this rate has changed over time or whether the methods modern humans choose for attempts are more effective than would have been chosen in the past. For example, while men commonly turn to firearms, which are a very effective way to commit suicide, women more often turn to prescription medication overdoses as a method, which overwhelmingly fails.

#3 is poisoning. While humans have always been around poisons, the sheer number that we keep in our houses, most of types that we didn't evolve to, suggests that this may be a stronger selective factor now than it was during our agrarian days, perhaps comparable to that when we were hunter-gatherers or worse.

#4 is homicide. We've definitely gotten a lot better at that, a person is far more likely to die from an intentional gunshot wound than a beating or stabbing. Selective pressures: surviving blood loss, mainly. Stronger, thicker bones may help in against low velocity penetrations.

#5 is other injuries. Again, we're not as likely to suffer from, say "crushed by a mastodon" as an injury, but we've developed plenty of new ways to get killed or maimed in our modern lives.

Then it gets more complicated on the basis that the issue isn't just about survival of the individual, but their social group as a whole, so even nonbreeding members can have a major impact...

Comment: Re:uh - by design? (Score 1) 160

by dgatwood (#48670849) Attached to: Thunderbolt Rootkit Vector

All drivers on OS X are already required to tell the operating system ahead of time that a device is about to DMA to memory. That's how that VT-d is able to configure the IOMMU hardware to allow those devices to access RAM without worrying about 64-bit address spaces. So the OS already knows precisely which pages of physical RAM should be accessible by PCIe devices using DMA. If other pages of RAM are accessible, that's a bug.

Similarly, making the Thunderbolt controller's IOMMU mappings be driven by that part of the kernel should not break any drivers at all, by definition, because PCIe devices shouldn't be issuing DMA requests except at driver-preapproved locations. So AFAIK, the only way such a fix could break any device would be if that device was trying to do something really dangerous, like reprogramming one of the PCI bus bridges, or reflashing the computer's EFI firmware....

I mean, I suppose that some drivers might be inadvertently configuring a mapping for a page of memory that also contains executable code or class instances (with function pointers), in which case fully fixing this would also require Apple to modify the IOMemoryDescriptor class to ensure that the DMA-enabled pages are whole pages owned by the descriptor, but that should still be pretty minor, and should result in only a modest amount of wired kernel memory bloat.

In the worst case, such a change might require a CPU-driven copy-on-prepare and/or copy-on-complete to work around drivers that provide their own virtual addresses for a memory descriptor that aren't page-aligned, which would cause a big performance hit for those few drivers, but I'd expect most driver developers to quickly fix those design mistakes to eliminate the performance hit. (And that's assuming this isn't done already—for some reason, I thought those buffers had to be page aligned or you'd get a panic, but I'm not seeing anything about it in the docs, so I might be remembering wrong.)

Comment: Re: Good news! (Score 1) 214

by lgw (#48670117) Attached to: Sony To Release the Interview Online Today; Apple Won't Play Ball

I've seen the flag-on-the-truck thing many times - never seen a confederate flag. While there are many in the South that still hate the damnyankees for the War of Northern Aggression, it's mostly pirate flags now. For a while I was confused - why were there so many Raiders fans across the South? But it's just the current generation's Rebel flag, without confusing the Northerners that it was about racism.

Comment: Re:I was suspicious from the moment they denied it (Score 1) 232

by Rei (#48670095) Attached to: Did North Korea Really Attack Sony?

To make a political statement? Since when was this "a political statement"? It was an attempt to stop a movie that made fun of the Great Leader. An attempt that mostly succeeded. Which was done after previously threatening Sony about the issue.

What, exactly, is to gain by admitting culpability? Is that usually what criminals do? "Why, yes, officer! I threw the brick through my ex's window to get back at her and scare her. I'm telling you now so that you can go ahead and punish me!"

Comment: Right. (Score 2) 232

by Rei (#48670077) Attached to: Did North Korea Really Attack Sony?

Because the world is just full of people who would hack a company to blackmail them not to release a movie about Kim Jong Un. Because everyone loves the Great Leader! His family's personality cult^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^HVoluntary Praise Actions only take up about 1/3rd of the North Korean budget. And I mean, they totally deserve it. I mean, did you know that his father was the world's greatest golf player who never had to defecate and whose birth was fortold by a swallow and heralded by a new star in the sky?

No, of course it wasn't North Korea. Clearly it was the work of America! Because America wants nothing more than a conflict with North Korea right now. Because clearly Russia and Syria and ISIS aren't enough, no, the US obviously has nothing better to do than to try to stir up things out of the blue with the Hollywood obsessed leader of a cult state whose family has gone so far as to kidnap filmmakers and force them to make movies for him. It all just makes so damn much sense!

Cue the conspiracy theorists in three, two, one...

Comment: Re:Interesting. I'd think the opposite (Score 3, Insightful) 195

by lgw (#48666741) Attached to: The World Is Not Falling Apart

conservatives saying "it was good enough for grandpa, it's fine, don't change anything".

I think you'll find most conservatives actually saying "it wasn't so terrible for grandpa, so let's see how this new untested idea actually makes it better". There will always be people opposed to any sort of change, of course, but don't confuse evidence-based (as opposed to "it looks good on paper, let's do it") and outcome-based (as opposed to "what matters is the lawmaker's intentions were good") with anti-progress. Any seasoned engineer will tell you that the way you'll make the best progress is to test before you ship, because it's so much less effort to fix mistakes that way.

Comment: Re:Many DDR3 modules? (Score 5, Informative) 124

by Rei (#48666531) Attached to: Many DDR3 Modules Vulnerable To Bit Rot By a Simple Program

If you're wanting to narrow it down, you won't like this line from the paper:

In particular, all modules manufactured in the past two years (2012 and 2013) were vulnerable,

It's pretty clever, and something I always wondered whether would be possible. They're exploiting the fact that DRAM rows need to be read every so often to refresh them because they leak charge, and eventually would fall below the noise threshold and be unreadable. Their exploit works by running code that - by heavily, cyclicly reading rows - makes adjacent rows leak faster than expected, leading to them falling below the noise threshold before they get refreshed.

Comment: Re:Sovereign default (Score 1) 255

by Rei (#48666131) Attached to: Serious Economic Crisis Looms In Russia, China May Help

Russia imports processed foods *and* staples. Just because there's some products that they're net positive on doesn't change that picture, their food imports are about 6x larger than their exports. And even some of your examples are off. For example, Russia exports a couple hundred million dollars of milk every year but imports 1 1/2 *billion* worth.

Russia's top ag imports are beef, beverges, pork, milk, tobacco, sugar and honey, poultry, and cheese. Beverages is mainly alcohol. So take beverages and tobacco out of the picture, you've still got mostly staples. And the funny thing is, see the milk and all that meat on the list? Russia's biggest subsidies to its ag industry are *already* on its meat and dairy production, and it still vastly underproduces.

It should also be noted that the very thing that keeps Russia's ag industry competitive at all has been its steady shift from lousy Soviet-era farm equipment to modern equipment. The vast majority of which (and spare parts to keep current systems operational) are imported.

Interchangeable parts won't.