Hello. One more thing: since kernel page-table isolation is already available on 32-Bit x86 systems (see Bug Description), maybe "SpectreAndMeltdown" information page (see 1.) should be updated, because of such a statement (see "Current Status"):
"No fix is currently available for Meltdown on 32-bit x86; moving to a 64-bit kernel is the currently recommended mitigation." Maybe, it could be changed to note, that: "32-bit x86 finally have kernel page-table isolation support to mitigate "Meltdown". It is already available in Linux kernel v4.19". Or above statement, available on "SpectreAndMeltdown" page, could be changed to: "Fix/mitigation for Meltdown on 32-bit x86 is already available in Linux v4.19 kernel". But that's just my opinion. Best regards. ______________ 1. https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/SpectreAndMeltdown#Current_Status -- 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/1790688 Title: x86/pti: 32-Bit x86 systems support already available. Status in linux package in Ubuntu: Confirmed Bug description: Hello. Linux kernel v4.19 release candidate [1], finally have kernel page- table isolation ('PTI', previously known as 'KAISER') support for x86_32 architecture. As we know, 'PTI' provides protection against attack, known as the "Meltdown" (CVE-2017-5754), that breaks isolation between user applications and the operating system etc. However, kernel page-table isolation wasn't available on 32-Bit x86 systems. Until now. So, I would like to ask a question: are there any plans to backport kernel page-table isolation patches for Linux kernels available in "Trusty"/14.04, "Xenial"/16.04 and "Bionic"/18.04 releases etc.? I mean x86_32 bit architecture, of course. I'm asking, because it seems, that pretty much no developers run 32-bit any more. However, there still are many 32-bit users out there. For more informations about how 'PTI' was implementing on 32-Bit x86 architecture, plase check - for example - commit '7757d607c6b31' ("x86/pti: Allow CONFIG_PAGE_TABLE_ISOLATION for x86_32"). Here are messages about 'PTI' support (PATCH v7, v8) for x86_32 [1]. Next, 'PTI' fixes for x86-32 [2] and more patches related to 'x86/mm/pti' [3]. There is also a short report for the first half of the 4.19 kernel merge window [4]. I'm sorry for such a long message, but I'm very happy that 'PTI' support is already available for x86_32 architecture and I hope, that it will be backported to all Ubuntu LTS releases etc. Thanks, best regards. ______________________ [1] http://lkml.iu.edu/hypermail/linux/kernel/1807.1/03578.html (please see every next patches etc.) http://lkml.iu.edu/hypermail/linux/kernel/1807.1/03181.html http://lkml.iu.edu/hypermail/linux/kernel/1807.2/02790.html [2] http://lkml.iu.edu/hypermail/linux/kernel/1808.0/05516.html [3] http://lkml.iu.edu/hypermail/linux/kernel/1807.1/03161.html [4] https://lwn.net/Articles/762566/ (See "Architecture-specific" changes) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1790688/+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
