[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

** Changed in: linux (Ubuntu) Status: Fix Committed => Fix Released -- 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/1732238 Title: arm64: Unfair rwlock can stall the system

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

This bug was fixed in the package linux - 4.13.0-36.40 --- linux (4.13.0-36.40) artful; urgency=medium * linux: 4.13.0-36.40 -proposed tracker (LP: #1750010) * Rebuild without "CVE-2017-5754 ARM64 KPTI fixes" patch set linux (4.13.0-35.39) artful; urgency=medium * linux:

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

Artful verification: I was able to successfully run the above stress-ng commmand w/o any errors on the console. ** Tags removed: verification-needed-artful ** Tags added: verification-done-artful -- You received this bug notification because you are a member of Kernel Packages, which is

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

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- artful' to 'verification-done-artful'. If the problem still exists, change the tag

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

** Changed in: linux (Ubuntu Artful) Status: Confirmed => Fix Committed -- 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/1732238 Title: arm64: Unfair rwlock can stall the system

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

** Changed in: linux (Ubuntu) Status: Confirmed => Fix Committed -- 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/1732238 Title: arm64: Unfair rwlock can stall the system Status

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

** Description changed: [Impact] There is a long-standing upstream bug with the ARM64 specific implementation of RW locks. The implementation can starve writers under lock contention leading to RCU stalls, driver timeouts and general system instability. [Test Case] $ stress-ng --kill

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

Example showing driver timeouts: ubuntu@boomer:~$ stress-ng --kill 0 -t 300 -v stress-ng: debug: [3344] 224 processors online, 224 processors configured stress-ng: info: [3344] dispatching hogs: 224 kill stress-ng: debug: [3344] /sys/devices/system/cpu/cpu0/cache does not exist stress-ng: info:

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

** Description changed: [Impact] - There is a long-standing upstream bug with the ARM64 specific implementation of RW locks. The implementation can starve writers under lock contention leading to RCU stalls and general system instability. + There is a long-standing upstream bug with the ARM64

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

This has been resolved with the following commits upstream: commit d133166146333e1f13fc81c0e6c43c8d99290a8a Author: Will Deacon locking/qrwlock: Prevent slowpath writers getting held up by fastpath commit 087133ac90763cd339b6b67f2998f87dcc136c52 Author: Will Deacon

[Kernel-packages] [Bug 1732238] Re: arm64: Unfair rwlock can stall the system

** Also affects: linux (Ubuntu Artful) Importance: Undecided Status: New ** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed ** Changed in: linux (Ubuntu Artful) Status: New => Confirmed ** Changed in: linux (Ubuntu) Assignee: (unassigned) => dann frazier