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Doubt regarding BIO handling
by Gaurav Mahajan Dec. 28, 2010

Dec. 28, 2010

Hi all, I have a doubt regarding the handling of bios. Suppose I receive a bio at some layer, and I want to split it into multiple bios. There are layers below the one I am working on and the final I/O operations will be handled by those layers. So, basically , after some processing, I want to hand over the bio to the lower layer. Now, if I have split the original bio into multiple bios and submitted all the newly formed bios, I shall receive each such bio in the bio->bio_end_io function. Here is it necessary to merge these bios so that the original bio can be formed or is it ok to just split the original bio, receive the requested data in multiple bios and leave it at that ? Looking forward to some help..... Regards, Gaurav

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update kn.org page with new ML address?
by Robert P. J. Day Dec. 27, 2010

Dec. 27, 2010

it might be a plan to update the mailing lists page: http://kernelnewbies.org/ML to refer to the new list address. rday -- ======================================================================== Robert P. J. Day Waterloo, Ontario, CANADA http://crashcourse.ca Twitter: http://twitter.com/rpjday LinkedIn: http://ca.linkedin.com/in/rpjday ========================================================================

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Re: final year project
by Prasad Joshi Dec. 27, 2010

Dec. 27, 2010

Forwarding reply from Madhavan back to mailing list. Madhavan, Please use reply to all. On Mon, Dec 27, 2010 at 9:20 AM, madhavan raghavan <coolmaddy999(a)gmail.com> wrote: > Hi , > > I interested in working on Scheduler part of kernel , I searching > for a project in Scheduler that can be done as a final year project . > > > Regards > Raghavan >

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Re: Reserving physical memory in Linux
by Adam Lee Dec. 27, 2010

Dec. 27, 2010

On Mon, Dec 27, 2010 at 5:06 PM, Asha R <rd.asha22(a)gmail.com> wrote: > Thanks Adam Lee. > Is this mem= or memmap=? Opps, sorry. It should be "memmap=256M$0x10000000" -- Regards, Adam Lee -------------------------------------------------- E-mail: adam8157(a)gmail.com Website: http://www.adam8157.info --------------------------------------------------

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final year project
by madhavan raghavan Dec. 26, 2010

Dec. 26, 2010

Hi everyone , I am final year student B.Tech , I want to do final year project on linux kernel , can someone help me out on how to start ? Regards Raghavan

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Re: Compiling for two different processors
by Alex John Dec. 26, 2010

Dec. 26, 2010

Hello, On Wed, 8 Dec 2010 15:46:36 +0700 Mulyadi Santosa <mulyadi.santosa(a)gmail.com> wrote: > Hi :) > > On Wed, Dec 8, 2010 at 15:16, John Mahoney <jmahoney(a)waav.com> wrote: > > Just a heads up. Try not to top post here. See my comment inline. > > > > On Dec 8, 2010, at 2:10 AM, Alex John <alex(a)archeleus.com> wrote: > > > >> Thanks, I'll compile for P4 then. > > > > I was just thinking and realized the core2 may have been based off > > the p3 arch and the p4 was a dead end, but normally with intel you > > can compile for the LCD, but I may have lied this time. Also, I > > believe one is 32bit and the other is 64bit, but a 32 bit kernel > > will work on both. > > I think Core 2 is more like "almost new" arch....I bet it tends to be > closer to newer Xeon (according to related Kbuild message) Apparently Core 2 is similar to the Coppermine T in some ways (such as netburst) but I think that its new as well since it's the model for quads, i7's etc; > > > If you want to guarantee it works on both I would compile for 32bit > > i386, but feel free to have some fun. If you do compile with p4 > > post if it worked on the core2, I am sort of interested now. > > > > I suggest to start with i686 first, then work gradually up > Compiled a generic for i686 and it worked perfectly with both processors, but then my old gentoo instincts kicked in and I compiled two different versions. Cheers - Alex.

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Re: copy_to_user
by Mulyadi Santosa Dec. 26, 2010

Dec. 26, 2010

On Fri, Dec 24, 2010 at 17:08, Hemanth Kumar <hemwire(a)yahoo.co.in> wrote: > Hi Mulyadi, > > Sorry sending mail the direclty,fixed the code with help of mailing list,once again sorry sending mail the directly, This time it's fine :) So, what's the solution? care to let us know? -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com

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Verify the frequency of a core
by pradeep hettiarachchi Dec. 25, 2010

Dec. 25, 2010

Hi, Here what I did: I set the "performance" governor for one of the cores and "ondemand" governor on an another core. Then I noticed that the cores have different frequencies. Based of the above observation on different processors, I have a couple of questions. 1) When I tried to frequency-scale in a core i7 processor, it allows me to set different governors for individual cores. As per to my understanding, the processor has 4 physical cores and 2 hardware threads per core. (totaling 8 cores altogether) This means, I should not be able to set different frequencies in two adjacent cores (say core 0 and core 1) as they both same hardware. My understanding is I should not be able to set the individual core frequencies as explained above. 2) When I played with Q6600 processor, I found that trough the governor, I can set the individual core-frequency. But as per to the literature, Intel does not provide a facility to frequency-scale in individual cores but the frequency in the entire processor. 3) What does the governor do? Does it set the frequency of the core directly ? 4) Is there any way that I can verify the actual frequency of a core other than the interface of the governor. Do you recommend to use MSR direly to change and measure the frequency of the system ? Sincerely, Pradeep M. Hettiarachchi

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Reading the VGA BIOS
by Prasad Joshi Dec. 25, 2010

Dec. 25, 2010

Hello All, Is there any way I can read the BIOS of the VGA card that is not being used? I have a two VGA cards, one onboard and one PCIe Nvidia card. The monitor is attached to the Nvidia card and the other card, is not being used. I can read the BIOS of the VGA card that is being used using /dev/mem, reading 64K from 0xC0000. This will read the BIOS of the Nvidia card. Similarly is there any way to read the BIOS of the other VGA card? I want to pass-through the other VGA card to the Virtual Machine. XEN has the pass-through support, they seem to be reading the BIOS from /dev/mem. But would not it attach the same graphics card to VM that is being used by the host machine, thus host machine will no longer have the display device. Thanks and Regards, Prasad

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KVM - virtualization support
by Sengottuvelan S Dec. 24, 2010

Dec. 24, 2010

Hi All, I am trying to see whether my kernel has KVM support or not. When i execute #egrep -c '(vmx|svm)' /proc/cpuinfo , output shows '0'' which means my custom kernel does not have capability of KVM. How do i enable or support KVM in my new kernel. Is it possible or not? Please someone throw light on this. -- Regards, S. Sengottuvelan.

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