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4

I will try to answer questions as briefly as possible. The questions you are asking are usually addressed in introductory operating systems courses at universities but I will assume you have not taken such a course. Memory isolation for userspace processes is very desirable - not only to protect the kernel from malicious userspace programs, but also to ...


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As it so happens, there is another significant interface with the kernel: the /proc and /sys virtual filesystems. While they do not hold regular files, their contents are direct gateways to the kernel: to act on them is to act directly on kernel-allocated memory. For instance, if you want to drop all memory caches, you may use... echo 3 > ...


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Well, from the apt-cache search linux-headers the cause should be obvious: Simply stated, the package isn't available in Ubuntu 14.10. You should instead install linux-headers-3.16.0-24, linux-headers-3.16.0-25 or save yourself from all problems and use linux-headers-generic which is a meta-package that depends on the latest available kernels (going by your ...


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You can use either dm-snapshot or NBD in copy-on-write mode. The dm-snapshot solution is provided here (sorry for not repeating it): https://raid.wiki.kernel.org/index.php/Recovering_a_failed_software_RAID#Making_the_harddisks_read-only_using_an_overlay_file As for NBD, you can install nbd-server and nbd-client, and then use it like this: mount ...


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You can use the modinfo command to give you all kind of information about a given module. For example: $ modinfo bluetooth filename: /lib/modules/3.17.4-1-ARCH/kernel/net/bluetooth/bluetooth.ko.gz alias: net-pf-31 license: GPL version: 2.19 description: Bluetooth Core ver 2.19 author: Marcel Holtmann ...


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Regarding Village's Bounty, all I can find is an archived mailing list post from August, 2011 stating that the preferred default before kernel commit r225076 was 32 GB, and up to 32 Slices for a Total of 1 TB of Ram (32^2 = 1024) After r225076 the limit per slice was removed, but the thread goes on to say that the practical limit should still be considered ...


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In order to read /proc/[pid]/mem, a process must now PTRACE_ATTACH to it. A commonly available utility that does this is gdb Pick a running process (in my case I just opened cat in another window), then attach gdb to that process: [root@qemu ~]# gdb --pid 423 #MORE OUTPUT 0xb771dbac in __kernel_vsyscall () As part of its output while loading symbols, gdb ...


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See Apple's promo page for info about Thunderbolt. It also describes how you can chain devices together instead of needing a hub or similar. My impression is that hot-plugging such daisy-chained devices are what are not supported by the linux commit; only single devices, whatever type they are.


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It depends. What do you mean by 'verify'? If you just want to monitor what syscalls some process is triggering then it's possible.. usually.... But if you feel like digging deeper then you're in trouble... I have not heard of any tools that could do that. You can use strace to see what syscalls some particular process is firing. Of course you'll have to ...


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On systems with udev (that's more or less all for several years) every recognized device has an entry in /dev. These entries can be deleted, though. But (I guess) without a device file it is not possible for a userland process to access a device. Of course, for a device file to work it just needs the correct major and minor number. It doesn't matter what ...


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By default, you should have user mode networking as explained in the docs: By default QEMU will create a SLiRP user network backend and an appropriate virtual network device for the guest (eg an E1000 PCI card for most x86 PC guests) If you want something better, consider tap networking: Add something like the following to your qemu command: -netdev ...


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In both cases those are not primarily warnings that break the build. For the kernel compilation: error: 'struct run_vap' has no member named 'beacon_mbuf' the compiler tells you, that the code is trying to access something that isn't there. This may have many reasons, but generally it suggests that the code is broken. Maybe you are trying to compile a ...


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Turns out to be a false warning. To quote from the (now closed) kernel bug report: Alfred Krohmer: If I unterstand your patch correctly it just removes the warning, but it won't actually fix the driver crash this bug report was submitted for. So why mark it as resolved? Emmanuel Grumbach: There is no real bug. The commit message explains this. ...



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