This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed- cosmic' to 'verification-done-cosmic'. If the problem still exists, change the tag 'verification-needed-cosmic' to 'verification-failed- cosmic'.
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you! ** Tags added: verification-needed-cosmic ** Tags added: verification-needed-bionic -- 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/1833410 Title: idle-page oopses when accessing page frames that are out of range Status in linux package in Ubuntu: In Progress Status in linux source package in Xenial: Fix Committed Status in linux source package in Bionic: Fix Committed Status in linux source package in Cosmic: Fix Committed Status in linux source package in Disco: Fix Committed Bug description: == SRU [Xenial][Bionic][Cosmic][Disco] == == Justification == When accessing page frames that are greater than max_pfn using the idle-page sysfs interface an oops is triggered that kills the process that writes to the sysfs interface. == Fix == Upstream fix currently in linux-next: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux- next.git/commit/mm/page_idle.c?id=d96d6145d9796d5f1eac242538d45559e9a23404 This fixes the maximum pfn threshold allowed. == Test == sudo stress-ng --idle-page 0 this should trigger the oops in ~50% of the cases due to the way the threshold calculation in the kernel was handling the maximum threshold based on pfn alignments. 31 of 63 of the times it may be under the threshold so no oops occurs. If it does not, increase or decrease the number of available pages in a system to trigger the sweet spot of the bug. == Regression Potential == Minimal, this touches a sysfs kernel interface that is not used much. The fix narrows the scope of touching specific page frames, so the page frame scope is reduced by the fix. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1833410/+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
