It turns out the issue also exists in the latest mainline kernel! The fix "x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAE" is there, but a later patch "x86/mm: Fix slow_virt_to_phys() to handle large PAT bit" (https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=34437e67a6727885bdf6cbfd8441b1ac43a1ee65) actually removed the fix unintentionally, so we have the regression...
I have made a new fix and post it to LKML just now (sta...@vger.kernel.org was Cc-ed): http://marc.info/?l=linux-kernel&m=145638841908383&w=2 -- 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/1549601 Title: [Hyper-V] x86,pageattr: prevent overflow in slow_virt_to_phys() for X86_PAE Status in linux package in Ubuntu: Incomplete Bug description: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d1cd1210834649ce1ca6bafe5ac25d2f40331343 x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAE pte_pfn() returns a PFN of long (32 bits in 32-PAE), so "long << PAGE_SHIFT" will overflow for PFNs above 4GB. Due to this issue, some Linux 32-PAE distros, running as guests on Hyper-V, with 5GB memory assigned, can't load the netvsc driver successfully and hence the synthetic network device can't work (we can use the kernel parameter mem=3000M to work around the issue). Cast pte_pfn() to phys_addr_t before shifting. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1549601/+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
