** Merge proposal linked: https://code.launchpad.net/~bryce/britney/+git/britney/+merge/406611
-- 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/1938474 Title: delve golang debugger can't read vvar on arm64 Status in Delve: Unknown Status in delve package in Ubuntu: New Status in linux package in Ubuntu: New Bug description: Also documented upstream: https://github.com/go-delve/delve/issues/2630 In version 1.6.1 of the delve golang debugger, a 'dump' feature was added. https://github.com/go-delve/delve/pull/2173 Since that time, arm64 autopkgtest of delve has been failing like so: https://autopkgtest.ubuntu.com/results/autopkgtest-impish/impish/arm64/d/delve/20210707_003312_d3699@/log.gz === RUN TestDump proc_test.go:5117: testing normal dump proc_test.go:5029: bad DumpState &proc.DumpState{Mutex:sync.Mutex{state:0, sema:0x0}, Dumping:false, AllDone:true, Canceled:false, DoneChan:(chan struct {})(nil), ThreadsDone:5, ThreadsTotal:5, MemDone:0x657b000, MemTotal:0x657d000, Err:error(nil)} --- FAIL: TestDump (0.98s) The test fails becaue MemDone != MemTotal. The decision on what to dump or not is based on smaps. The failing item is vvar. err when attempting to read is error(syscall.Errno) golang.org/x/sys/unix.EIO (5) Notably however, this test passes in debian CI. (kernel 4.19) Also, running on older series such as bionic/focal does pass. vvar section from vm with kernel 5.4 (test pass): ffff924a4000-ffff924a5000 r--p 00000000 00:00 0 [vvar] Size: 4 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Rss: 0 kB Pss: 0 kB Shared_Clean: 0 kB Shared_Dirty: 0 kB Private_Clean: 0 kB Private_Dirty: 0 kB Referenced: 0 kB Anonymous: 0 kB LazyFree: 0 kB AnonHugePages: 0 kB ShmemPmdMapped: 0 kB FilePmdMapped: 0 kB Shared_Hugetlb: 0 kB Private_Hugetlb: 0 kB Swap: 0 kB SwapPss: 0 kB Locked: 0 kB THPeligible: 0 VmFlags: rd mr de vvar from failing case ffffac144000-ffffac146000 r--p 00000000 00:00 0 [vvar] Size: 8 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Rss: 0 kB Pss: 0 kB Shared_Clean: 0 kB Shared_Dirty: 0 kB Private_Clean: 0 kB Private_Dirty: 0 kB Referenced: 0 kB Anonymous: 0 kB LazyFree: 0 kB AnonHugePages: 0 kB ShmemPmdMapped: 0 kB FilePmdMapped: 0 kB Shared_Hugetlb: 0 kB Private_Hugetlb: 0 kB Swap: 0 kB SwapPss: 0 kB Locked: 0 kB THPeligible: 0 VmFlags: rd mr pf de Two noticible differences 1) 4kB vs 8kB size 2) Failing case adds the "pf" flag ("pure PFN range") Open questions: 1) Would we expect that a debugger could read vvar on arm64? 2) Any thoughts on why this seems to work on older kernels? 3) Do we believe this to be a kernel bug, or should the delve debugger not expect to read vvar? 4) Is it sensible for a debugger to attempt to read things with the "pf" flag? Note that the "dd" ("do not include area into core dump") flag is not set. ProblemType: Bug DistroRelease: Ubuntu 21.10 Package: linux-image-5.11.0-20-generic 5.11.0-20.21+21.10.1 ProcVersionSignature: Ubuntu 5.11.0-20.21+21.10.1-generic 5.11.21 Uname: Linux 5.11.0-20-generic aarch64 AlsaDevices: total 0 crw-rw---- 1 root audio 116, 1 Jul 29 21:21 seq crw-rw---- 1 root audio 116, 33 Jul 29 21:21 timer AplayDevices: Error: [Errno 2] No such file or directory: 'aplay' ApportVersion: 2.20.11-0ubuntu67 Architecture: arm64 ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord' AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: CasperMD5CheckResult: pass Date: Thu Jul 29 21:34:34 2021 InstallationDate: Installed on 2021-07-29 (0 days ago) InstallationMedia: Ubuntu-Server 21.10 "Impish Indri" - Alpha arm64 (20210729) IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig' Lsusb: Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Lsusb-t: /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 5000M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M MachineType: QEMU QEMU Virtual Machine PciMultimedia: ProcEnviron: TERM=screen-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=C.UTF-8 SHELL=/bin/bash ProcFB: ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-5.11.0-20-generic root=/dev/mapper/username--vg-username--lv ro RelatedPackageVersions: linux-restricted-modules-5.11.0-20-generic N/A linux-backports-modules-5.11.0-20-generic N/A linux-firmware 1.199 RfKill: Error: [Errno 2] No such file or directory: 'rfkill' SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 02/06/2015 dmi.bios.release: 0.0 dmi.bios.vendor: EFI Development Kit II / OVMF dmi.bios.version: 0.0.0 dmi.chassis.type: 1 dmi.chassis.vendor: QEMU dmi.chassis.version: virt-5.2 dmi.modalias: dmi:bvnEFIDevelopmentKitII/OVMF:bvr0.0.0:bd02/06/2015:br0.0:svnQEMU:pnQEMUVirtualMachine:pvrvirt-5.2:cvnQEMU:ct1:cvrvirt-5.2: dmi.product.name: QEMU Virtual Machine dmi.product.version: virt-5.2 dmi.sys.vendor: QEMU To manage notifications about this bug go to: https://bugs.launchpad.net/delve/+bug/1938474/+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
