Thanks for the update, Chris. The patch "storvsc: use small sg_tablesize on x86" has not landed in mainline yet, but I can submit an SRU request to include it as an Ubuntu SAUCE patch.
However, for Trusty I think we need to increase MAX_PAGE_BUFFER_COUNT in addition to the patch "storvsc: use small sg_tablesize on x86". In my testing a Trusty kernel with only the storvsc patch will still panic. But a Trusty kernel with the storvsc patch and a value of 32 for MAX_PAGE_BUFFER_COUNT will not panic. There was actually a commit in v3.15-rc1, written by KY: commit 7e5ec36834a5752304dc0751dfab42ba6ad64a85 Author: K. Y. Srinivasan <k...@microsoft.com> Date: Fri Mar 7 00:10:34 2014 -0800 Drivers: hv: vmbus: Increase the limit on the number of pfns we can handle So for Trusty I think we need commit 7e5ec368 and the patch "storvsc: use small sg_tablesize on x86". I built two Trusty test kernels. One has only the "storvsc: use small sg_tablesize on x86" patch. The other has a cherry pick of commit 7e5ec368 and the "storvsc: use small sg_tablesize on x86" patch. Ovidiu R, if you have a chance can you test these two kernels? Before I submit the new patch, I'd like to confirm if we also need commit 7e5ec368 or not. Test kernel with only the new patch: http://kernel.ubuntu.com/~jsalisbury/lp1495983/patched-kernel/trusty/trusty-with-only-use-small-sg_tablesize/ Test kernel with the new patch and a cherry pick of 7e5ec368: http://kernel.ubuntu.com/~jsalisbury/lp1495983/patched-kernel/trusty/trusty-with-use-small-sg_tablesizeANDCommit7e5ec368/ -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1495983 Title: [Hyper-V] kernel panic occurs when installing Ubuntu Server 15.10 x32 Status in linux package in Ubuntu: In Progress Status in linux source package in Trusty: In Progress Status in linux source package in Vivid: In Progress Status in linux source package in Wily: In Progress Bug description: Attempting to install the latest build of Ubuntu Server 15.10 (Wily Werewolf) x32 on Hyper-V, after beginning installation a kernel panic occurs. The console log from the serial output is attached. http://cdimage.ubuntu.com/ubuntu-server/daily/current/ I tried with the builds from 14th and 15th of September with the same result. This bug does not affect x64 builds. Tried to start the installation with different resources with no effect, kernel panic always occurs no matter the VM settings. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1495983/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp