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02 9月 2018 - 10:51:55

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The models at risk are the 300E5C, NP700Z5C, NP700Z7C, and 530U3C series of Sammy PC laptops.At first the fault was tracked down to a Linux kernel hardware driver that was quickly disabled by developers to protect users' machines when booting open-source Linux. Greg Kroah-Hartman, who built the Samsung-laptop driver with Samsung's help, advised people to "blacklist" the kernel module to avoid any heartbreak.But Garrett took to his personal blog on Friday night to urge people to boot their Samsung laptops in old-fashioned BIOS mode rather than the new UEFI standard, regardless of their OS choice, to avoid catastrophe. He said motherboard death could be caused by any code, not just Linux, that tries to write to the firmware's built-in storage area.He wrote of the firmware-destroying flaw: "The information we now have indicates that there are other ways of triggering this."According to Garrett, the disastrous bug is set off by writing too much information to the UEFI firmware's variables space, which causes a fatal error after a restart.

It is understood that Linux, when installing itself on the vulnerable laptops, triggers an exception and writes "too much" diagnostic data to the firmware's memory. According to the UEFI specification, it should not be possible to kill a computer by trying to storing too much information in the firmware but Sammy's hardware manages to do just that.Microsoft's Windows could therefore potentially trip up just like Linux if it's not too careful: the open-source OS dumps 10KB of data into the firmware if the machine completely crashes. Windows 8 expects to be able to write 64KB into this variables storage area. But Garrett said he was able to brick his laptop by writing just 36KB to the Samsung UEFI from Windows."It also seems likely that it's possible for a user-space application to cause the same problem under Windows," Garrett added, providing a proof-of-concept program with source code to show he could ruin his machine from Windows. He said he ran the program "as an administrator under Windows and then rebooted the system. It never came back".Garrett, who works as a power management, mobile and firmware developer on Linux, said more work is being done to figure out the full details.

Probably the most useful alternatives to SRT are the solid-state cache drives offered by the likes of Corsair, Crucial and OCZ with their Accelerator, Adrenaline and Synapse products. These three and others use Nvelo’s Dataplex caching software. The software works with AMD as well as Intel chipsets - so it’s the obvious choice for folk with a dislike of Chipzilla products - but doesn’t support chipsets produced by Nvidia. These cache drives have another distinct advantage over Intel’s technology: you don’t have to disturb your original setup. Just fit the cache drive, download and install the software, tell it which is the drive being cached, and off you go. To make sure that the Dataplex install has worked and the drive is in cache mode, there is a utility included to allow you to check all is well.That’s all well and good, but what about laptop users who generally only have space for one drive in their machines? For these folk there is the hybrid drive: an HDD with a NAND Flash cache built in. Both Seagate and Samsung introduced hybrid drives a few years back and, it must be said, these early drives didn’t set the world on fire. Undeterred by this reaction, Seagate kept on with the concept and in early 2010 launched the Momentus XT range, a 2.5in drive is available as a first-generation drive with a 3Gb/s Sata interface and 500GB capacity, and as a second-generation 750GB unit with a 6Gb/s interface. The two are priced at £84 and £99, respectively. Both come with a 7200rpm spin speed and 32MB of normal cache. The 500GB drive has 4GB of SLC NAND while the 750GB has 8GB. WD is expected to launch a hybrid drive soon.

In Windows 7, Microsoft turned off file defragmentation for SSDs, but with Windows 8 it’s back, albeit in a different guise. The new Storage Optimizer utility handles different kinds of storage in different ways. If it sees a standard hard disk in the system, it will regularly defrag it in the normal way to ensure file data is kept in contiguous sectors. However, if it sees an SSD, it will send a complete set of Trim hints for the entire volume. To make sure that the OS knows what drives or what kinds are in the system you need to run the Windows Experience Index at least once.Real-time Trim hints are sent to the drive when the file system moves or deletes files, but the drive may not be able to react to the hints if it’s writing or erasing. The Storage Optimizer resends these hints when the system is in an idle state to make sure the SSD can react to them.

To explore the potential desktop performance benefits of Intel’s SRT technology and of SSD cache drives over a standard large capacity hard drive, I used an Asus P8Z77-V Premium motherboard which, as well as supporting SRT, comes with a 32GB LiteOn mSATA SSD already installed. I also had to hand a 30GB Corsair Accelerator (£47) SSD cache drive, which also comes in 45GB (£55) and 60GB (£80) capacities. I’ve a Crucial Adrenaline (£60) which comes in just one flavour, 50GB, too. I used both this 2.5in drive and the 30GB, 2.5in Corsair as alternatives to Intel’s technology. For the mechanical drive, I used one of Western Digital’s latest 4TB Black drives, a fast performer with a 7200rpm spin speed and 64MB of cache. I then threw a 120GB Scandisk Extreme SSD into the mix, a reasonably fast drive which you can pick up for around the £75 mark if you shop around.

To get a feel of how the various caching technologies would work in a real life situation, I used Futuremark’s PCMark 07 benchmark suite. This provides various tests that mimic the kind of workloads a desktop or notebook PC might go through on a daily basis. The Gaming workload uses a trace of World of Warcraft being started up. Starting Apps is a trace of home and office productivity applications being started up, Importing Pictures uses a trace of 434MB of images being imported into Windows Live Photo Gallery, and the Windows Defender workload is a trace of the application running a quick scan of the system.I ran the PCMark 07 benchmark four times to give the cache drive time to ‘learn’ which were the most accessed I/O blocks, and used the fourth run as the result to record.Pew found that 61 per cent of current US users felt they needed a break from the social network, voluntarily abstaining from baby milestone status updates, pictures of breakfast and videos of kittens for several weeks or more.

And the main reason Facebookers stopped logging on wasn't because they were worried about their privacy or anything like that. Half of them either didn't have time for it, weren't interested anymore, thought it was a waste of time or felt that there was too much drama and negativity on the social network.A sample of the users' comments on quitting eternal contact with everyone they've ever known, even those people they don't remember from school, included:Over in penguin city, that pesky problem of innocent Linux-lovers bricking their Samsung laptops when they try to boot the OS on them has been solved by penguin-in-chief Linus Torvalds with the simple and expedient instruction to disable the dodgy driver in question.Fellow Linux kernel developer Greg Kroah-Hartman was somewhat puzzled as to how a driver he'd actually had a hand in could have been so technologically lethal:Who would have thought that just randomly poking memory of a laptop would brick it. Long ago Samsung told me that it was just fine to be doing this, and that there would not be any problems (I based the Samsung-laptop driver on code that Samsung themselves gave me.)

And the GNOME desktop for Linux has decided that JavaScript is the only "first class" language it's going to be recommending to app builders. Sick and tired of warring GNOMEs using eight different languages, developer Travis Reitter cut through the battles to ensure that GNOMEs aren't ignored by app developers.Now that finally there is some consensus, we can all move forward and GNOME can concentrate on making a kick ass development platform that can focus on the little things like great docs, best practices and tight language integration.They can do all this without the distraction of “but that isn’t how it is done in <insert your favorite language here>”. Seriously, if someone brings that up in a discussion they can now be thoroughly ignored.Meanwhile, Twitter was hacked this week and up to 250,000 users' data was slurped, albeit in a "limited" form. The microblogging site immediately shut down and scrabbled to shunt the hackers off the site once their "unusual patterns" were noticed, but didn't manage it until after they'd made off with some data.

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