You have been subscribed to a public bug: In order to address variant 3 on IBM POWER systems we must flush the L1D cache on return from exceptions into userspace. We do this by leveraging conveniently newly added nop space instructions that have the effect of guaranteeing a given kernel VA is not present in the L1 cache upon return to user (on POWER, such loads can only happen explicitly under kernel control, so this is an alternative to the KAISER/KPTI patches for this architecture). The new feature is known as "rfi_flush" and is runtime controllable via sysfs.
** Affects: linux (Ubuntu) Importance: Undecided Assignee: Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage) Status: New ** Tags: architecture-ppc64le bugnameltc-163123 severity-critical targetmilestone-inin1710 -- powerpc: flush L1D on return to use https://bugs.launchpad.net/bugs/1741497 You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. -- 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