------- Comment From mranw...@us.ibm.com 2019-04-29 17:43 EDT------- I did some more testing, including toggling /sys/kernel/debug/powerpc/count_cache_flush and checking the code in xmon before: c00000000000db58 7ee00026 mfcr r23 c00000000000db5c fae101a0 std r23,416(r1) c00000000000db60 f8230000 std r1,0(r3) c00000000000db64 4bffdb1d bl c00000000000b680 # flush_count_cache+0x0/0x2480
and after: c00000000000db58 7ee00026 mfcr r23 c00000000000db5c fae101a0 std r23,416(r1) c00000000000db60 f8230000 std r1,0(r3) c00000000000db64 60000000 nop All looks correct. Thanks for flipping the tag, I think it looks good. I'll run some regression on it now, too. -- 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/1822870 Title: Backport support for software count cache flush Spectre v2 mitigation. (CVE) (required for POWER9 DD2.3) Status in The Ubuntu-power-systems project: Fix Committed Status in linux package in Ubuntu: Fix Released Status in linux source package in Bionic: Fix Committed Status in linux source package in Cosmic: Fix Released Bug description: [IMPACT] Need to further address the Spectre v2 and Meltdown vulnerability in Power with software count cache flush Spectre v2 mitigation support for Power9 DD2.3, and additional Spectre/Meltdown related patches for Power9. [Fix] List of upstream patches identified by IBM in comment #4, #5, and #8. [Test] Pre-req: requires Power9 DD2.3 hardware. A test kernel is available in PPA ppa:ubuntu-power-triage/lp1822870 and the kernel was tested by IBM. Please see comment #11 and #14 for details. [REGRESSION POTENTIAL] The patches are isolated to the ppc64el architecture and does not impact generic code. ppc64el test kernel was tested by IBM and no regressions were reported. [OTHER INFO] For the different kernels: The HWE a563fd9c62f0 UBUNTU: Ubuntu-hwe-4.18.0-17.18~18.04.1 appears to have all patches. Disco appears to be missing only this patch: 92edf8df0ff2ae86cc632eeca0e651fd8431d40d powerpc/security: Fix spectre_v2 reporting Cosmic (which is supported until July) is missing a number of patches: cf175dc315f90185128fb061dc05b6fbb211aa2f powerpc/64: Disable the speculation barrier from the command line 6453b532f2c8856a80381e6b9a1f5ea2f12294df powerpc/64: Make stf barrier PPC_BOOK3S_64 specific. 179ab1cbf883575c3a585bcfc0f2160f1d22a149 powerpc/64: Add CONFIG_PPC_BARRIER_NOSPEC af375eefbfb27cbb5b831984e66d724a40d26b5c powerpc/64: Call setup_barrier_nospec() from setup_arch() 406d2b6ae3420f5bb2b3db6986dc6f0b6dbb637b powerpc/64: Make meltdown reporting Book3S 64 specific 06d0bbc6d0f56dacac3a79900e9a9a0d5972d818 powerpc/asm: Add a patch_site macro & helpers for patching instructions dc8c6cce9a26a51fc19961accb978217a3ba8c75 powerpc/64s: Add new security feature flags for count cache flush ee13cb249fabdff8b90aaff61add347749280087 powerpc/64s: Add support for software count cache flush ba72dc171954b782a79d25e0f4b3ed91090c3b1e powerpc/pseries: Query hypervisor for count cache flush settings 99d54754d3d5f896a8f616b0b6520662bc99d66b powerpc/powernv: Query firmware for count cache flush settings 7d8bad99ba5a22892f0cad6881289fdc3875a930 powerpc/fsl: Fix spectre_v2 mitigations reporting 92edf8df0ff2ae86cc632eeca0e651fd8431d40d powerpc/security: Fix spectre_v2 reporting This appears to already be in -next. For the bionic 18.04.1 (4.15) kernel only this patch is already part of master-next: a6b3964ad71a61bb7c61d80a60bea7d42187b2eb powerpc/64s: Add barrier_nospec The others are ported, there were only 3 that were not clean. Those are: 2eea7f067f495e33b8b116b35b5988ab2b8aec55 powerpc/64s: Add support for ori barrier_nospec patching This failed because commit a048a07d7f4535baa4cbad6bc024f175317ab938 is missing, but it does not look like that is required here. cb3d6759a93c6d0aea1c10deb6d00e111c29c19c powerpc/64s: Enable barrier_nospec based on firmware settings This failed because debugfs was already included, I can see that previously added, I didn't see where it was previously removed. 06d0bbc6d0f56dacac3a79900e9a9a0d5972d818 powerpc/asm: Add a patch_site macro & helpers for patching instructions This failed because 8183d99f4a22c is not included - but doesn't seem necessary. All other patches applied with, at most, some fuzz. Has had a little testing - boots, check debugfs, etc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1822870/+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
