[gentoo-user] Re: A helping hand with virtual machines, please.
The 22/11/11, Alan McKinnon wrote: I use virtualbox and it's the one I recommend. The kernel modules are no better and no worse than any other out-of-tree modules. You're wrong. Using the virtualbox module means you turn the kernel to tained crap because of the number of problems it causes, including random memory curruption. -- Nicolas Sebrecht
Re: [gentoo-user] Re: A helping hand with virtual machines, please.
On Wed, 23 Nov 2011 10:17:07 +0100 Nicolas Sebrecht nsebre...@piing.fr wrote: The 22/11/11, Alan McKinnon wrote: I use virtualbox and it's the one I recommend. The kernel modules are no better and no worse than any other out-of-tree modules. You're wrong. Using the virtualbox module means you turn the kernel to tained crap because of the number of problems it causes, including random memory curruption. Care to back that up with something resembling evidence? EVERY out-of-tree module will taint the kernel. As to whether it deserves the crap moniker is a matter of opinion -- Alan McKinnnon alan.mckin...@gmail.com
[gentoo-user] Re: A helping hand with virtual machines, please.
The 23/11/11, Alan McKinnon wrote: On Wed, 23 Nov 2011 10:17:07 +0100 Nicolas Sebrecht nsebre...@piing.fr wrote: You're wrong. Using the virtualbox module means you turn the kernel to tained crap because of the number of problems it causes, including random memory curruption. Care to back that up with something resembling evidence? EVERY out-of-tree module will taint the kernel. But not all virtualization solutions use out-of-tree module and from those coming out-of-tree, few are taint as crap. As to whether it deserves the crap moniker is a matter of opinion ...I'd rather say a matter of facts. :-) Every one is free to support virtualbox but forgetting to talk about this taint level is not very fair, FMPOV. -- Nicolas Sebrecht
Re: [gentoo-user] Re: A helping hand with virtual machines, please.
I agree a list of issues, just broad ones, would be helpful. I am interested in VMs, so knowing which ones have what problems, and my own needs, would be help me make a good choice. Please, disparage with details! ;-) Thanks - Joseph Nicolas Sebrecht wrote: The 23/11/11, Alan McKinnon wrote: On Wed, 23 Nov 2011 10:17:07 +0100 Nicolas Sebrecht nsebre...@piing.fr wrote: You're wrong. Using the virtualbox module means you turn the kernel to tained crap because of the number of problems it causes, including random memory curruption. Care to back that up with something resembling evidence? EVERY out-of-tree module will taint the kernel. But not all virtualization solutions use out-of-tree module and from those coming out-of-tree, few are taint as crap. As to whether it deserves the crap moniker is a matter of opinion ...I'd rather say a matter of facts. :-) Every one is free to support virtualbox but forgetting to talk about this taint level is not very fair, FMPOV. -- University of Houston, Cougar Card services support.
[gentoo-user] Re: A helping hand with virtual machines, please.
The 23/11/11, Joseph Davis wrote: I agree a list of issues, just broad ones, would be helpful. I am interested in VMs, so knowing which ones have what problems, and my own needs, would be help me make a good choice. Please, disparage with details! ;-) I've already said random memory curruption. random is the key word explaining why not much details can be given. :) -- Nicolas Sebrecht
Re: [gentoo-user] Re: A helping hand with virtual machines, please.
On Wed, November 23, 2011 1:59 pm, Nicolas Sebrecht wrote: The 23/11/11, Joseph Davis wrote: I agree a list of issues, just broad ones, would be helpful. I am interested in VMs, so knowing which ones have what problems, and my own needs, would be help me make a good choice. Please, disparage with details! ;-) I've already said random memory curruption. random is the key word explaining why not much details can be given. :) I also got random memory corruption when compiling large packages with simple kernel configurations and no out-of-tree modules present on the system. Do you have any evidence to proof that this randomness is actually caused by VB modules and not something else? -- Joost
Re: [gentoo-user] Re: A helping hand with virtual machines, please.
On Wed, Nov 23, 2011 at 3:21 AM, Alan McKinnon alan.mckin...@gmail.com wrote: On Wed, 23 Nov 2011 10:17:07 +0100 Nicolas Sebrecht nsebre...@piing.fr wrote: The 22/11/11, Alan McKinnon wrote: I use virtualbox and it's the one I recommend. The kernel modules are no better and no worse than any other out-of-tree modules. You're wrong. Using the virtualbox module means you turn the kernel to tained crap because of the number of problems it causes, including random memory curruption. Care to back that up with something resembling evidence? EVERY out-of-tree module will taint the kernel. As to whether it deserves the crap moniker is a matter of opinion -- Alan McKinnnon alan.mckin...@gmail.com Alan, I'm a happy Virtualbox user so I was surprised to see this post on the LKML which I suspect pushed the consciousness of this a bit more to the forefront: https://lkml.org/lkml/2011/10/6/317 Now, I have no problems with Virtualbox but I have no reason to disbelieve these folks either. As with a lot of these things, it's the devil you know or the devil you don't know. I suspect the other less used solutions also have problems but not as many users, etc. - Mark
[gentoo-user] Re: A helping hand with virtual machines, please.
The 23/11/11, J. Roeleveld wrote: I also got random memory corruption when compiling large packages with simple kernel configurations and no out-of-tree modules present on the system. Do you have any evidence to proof that this randomness is actually caused by VB modules and not something else? This is a question you should ask to the kernel developers. You're free to not trust them, of course. I'll still think they are at a much better place than yours to tell which driver are crap and which are not. -- Nicolas Sebrecht
[gentoo-user] Re: A helping hand with virtual machines, please.
On 2011-11-23, J. Roeleveld jo...@antarean.org wrote: On Wed, November 23, 2011 12:06 am, Neil Bothwick wrote: On Tue, 22 Nov 2011 22:29:23 +0200, Alan McKinnon wrote: What I like about VBox is that you get all the useful bits in the open-source version. Except USB support. Huh? The last time I checked, USB support is not available in the open-source version of VB -- only in the binary-only version. I used VirtualBox with a MSWindowsXP guest to use a negatives scanner that would refuse to work with Sane as the device has some weird initialization routines that need to be controlled by the actual driver. The connection was with USB and worked perfectly. I doubt USB support has disappeared suddenly. And you're using the open-source VB? -- Grant Edwards grant.b.edwardsYow! I'll eat ANYTHING at that's BRIGHT BLUE!! gmail.com
Re: [gentoo-user] Re: A helping hand with virtual machines, please.
On Wed, 23 Nov 2011 05:51:19 -0800 Mark Knecht markkne...@gmail.com wrote: On Wed, Nov 23, 2011 at 3:21 AM, Alan McKinnon alan.mckin...@gmail.com wrote: On Wed, 23 Nov 2011 10:17:07 +0100 Nicolas Sebrecht nsebre...@piing.fr wrote: The 22/11/11, Alan McKinnon wrote: I use virtualbox and it's the one I recommend. The kernel modules are no better and no worse than any other out-of-tree modules. You're wrong. Using the virtualbox module means you turn the kernel to tained crap because of the number of problems it causes, including random memory curruption. Care to back that up with something resembling evidence? EVERY out-of-tree module will taint the kernel. As to whether it deserves the crap moniker is a matter of opinion -- Alan McKinnnon alan.mckin...@gmail.com Alan, I'm a happy Virtualbox user so I was surprised to see this post on the LKML which I suspect pushed the consciousness of this a bit more to the forefront: https://lkml.org/lkml/2011/10/6/317 Now, I have no problems with Virtualbox but I have no reason to disbelieve these folks either. As with a lot of these things, it's the devil you know or the devil you don't know. I suspect the other less used solutions also have problems but not as many users, etc. - Mark Mark, I too am a happy VirtualBox user. I find it works better and is far more stable than either VMWare or Nvidia drivers. Or Flash for that matter. I also know the Linux kernel devs have incredibly high standards - mere perfection is often just not good enough - a very good trait in a dev. I put it down to a distinct lack of technical design not being driven by a corporate Sales department :-) Having said that, Dave's mail sounds a lot like me sounding off on a good day after the Nth clueless user pissed me off one time too many - he makes a startling claim and then proceeds to not back it up, but just rant. Lets grant that the VirtualBox modules are not up to LKML standards. That's fine, very little out of the tree is. I'm willing to bet that the majority of the issues are silly bugs involving pointer arithmetic (the usual cause of these things) and could be fixed up with minimal effort. Either way I don't think a sweeping condemnation of the entire product is the right way to go. Oh, I forgot something in the first paragraph. In my experience on this machine we can add Firefox, OpenOffice.org and LibreOffice to the same list of unstable software. -- Alan McKinnnon alan.mckin...@gmail.com
Re: [gentoo-user] Re: A helping hand with virtual machines, please.
On Wed, Nov 23, 2011 at 10:09 AM, Alan McKinnon alan.mckin...@gmail.com wrote: Lets grant that the VirtualBox modules are not up to LKML standards. That's fine, very little out of the tree is. I'm willing to bet that the majority of the issues are silly bugs involving pointer arithmetic (the usual cause of these things) and could be fixed up with minimal effort. Either way I don't think a sweeping condemnation of the entire product is the right way to go. I read that entire thread back when it was highlighted on /. 1) The vbox driver is buggy. 2) The vbox driver is buggy in ways that cause crashes which are difficult to debug and correctly attribute, which appears to be discerned by statistical means. 3) The vbox driver upstream won't send their code to the kernel where it could be cleaned up and kept in step with the rest of the kernel, because it would restrict them from updating their API in future versions. 4) The vbox driver functions as a wildcard when kernel devs are trying to deal with bug reports in other areas of the code; just like heap and stack corruption in userland apps are a royal PITA to deal with, so are the same in kernelspace. The vbox driver is known to cause these problems, so they don't want to deal with it. Now, it looks like things may be in line to get better; the thread got the attention of the vbox maintainers, and they started working on ways to get flagged bug reports sent their way. That'll improve the feedback they get. The code will probably improve as a result. That said, drivers which cause random memory corruption are *not* ones I want loaded into my kernel. Discussions around things like the vbox kernel give me second thoughts about sweet dreams of mmapping persistent storage block devices contiguously in a large address space; I'd suddenly rather keep the window target small. I've got nothing against proprietary drivers if they're good. I've generally had good luck with both NVidia and ATI, for example. NVidia, especially, has been quick to respond to issues by their user communities Oh, I forgot something in the first paragraph. In my experience on this machine we can add Firefox, OpenOffice.org and LibreOffice to the same list of unstable software. Apples and oranges. FF, OO and LO don't crash the entire system when they go up. Protected memory FTW. Kernelspace stuff must be held to a higher standard; they run in ring 0. (Forgive the x86-specific terminology, but it should be analogous for any protected-memory platform) -- :wq
