------- Comment From geral...@de.ibm.com 2020-11-20 09:50 EDT------- (In reply to comment #14) > suggested bionic backport for /mm/page_idle.c
Hmm, not sure if I read this diff correcty, but it seems to remove struct zone and spinlock, which would not be right, and introduce a new bug. The reason why the upstream commit does not apply directly to bionic, is because of conflicting context. The "struct zone" was replaced with "pg_data_t *pgdat" by (another) commit 92fb1db26eef, but that change (or any change to the struct zone) would not be necessary to fix the uninitialized struct page access. So, I would suggest simply replacing the line pg_data_t *pgdat; from the upstream commit context, with this line to fix the context for bionic struct zone *zone; Removing struct zone and the spinlock would certainly introduce a new bug, because the spinlock is necessary. -- 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/1904884 Title: s390: dbginfo.sh triggers kernel panic, reading from /sys/kernel/mm/page_idle/bitmap Status in Ubuntu on IBM z Systems: Triaged Status in linux package in Ubuntu: Fix Released Status in linux source package in Bionic: New Status in linux source package in Focal: New Status in linux source package in Groovy: Fix Released Status in linux source package in Hirsute: Fix Released Bug description: System hangs on dbginfo.sh script execution. Solution: Commit 92fb1db26eef ("mm/page_idle.c: skip offline pages") Included upstream since kernel v5.8, so it is already included in Ubuntu 20.10, but not in 20.04 and earlier. Commit 92fb1db26eef ("mm/page_idle.c: skip offline pages") applies cleanly on ubuntu-focal, but not on ubuntu-bionic. Adjustment / backport for bionic should be trivial, but it is not IBM code and therefore the backport will be requested here by Canonical. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1904884/+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
