** Also affects: linux (Ubuntu Trusty) Importance: Undecided Status: New
** Also affects: linux (Ubuntu Utopic) Importance: Undecided Status: Incomplete ** Changed in: linux (Ubuntu Trusty) Status: New => In Progress ** Changed in: linux (Ubuntu Trusty) Assignee: (unassigned) => Dave Chiluk (chiluk) ** Changed in: linux (Ubuntu Utopic) Status: Incomplete => 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/1354157 Title: Soft Lockup in shrink_dentry_list+0x4e/0xe0 Status in “linux” package in Ubuntu: Fix Released Status in “linux” source package in Trusty: In Progress Status in “linux” source package in Utopic: Fix Released Bug description: BUG: soft lockup - CPU#1 stuck for 23s! [test.sh:1928] Kernel panic - not syncing: softlockup: hung tasks CPU: 1 PID: 1928 Comm: test.sh Tainted: G W 3.13.0-24-generic #47-Ubuntu Hardware name: NEC Mercury CPU Module [NQ2250-902]/GC-MDC10-NJ, BIOS 5.6.0005 03/05/2014 000000000000419b ffff88017fc43e28 ffffffff81715ac4 ffffffff81a5ee64 ffff88017fc43ea0 ffffffff8170ecc5 0000000000000008 ffff88017fc43eb0 ffff88017fc43e50 0000000000000086 00000000a954a952 0000000000000007 Call Trace: <IRQ> [<ffffffff81715ac4>] dump_stack+0x45/0x56 [<ffffffff8170ecc5>] panic+0xc8/0x1d7 [<ffffffff8110d015>] watchdog_timer_fn+0x165/0x170 [<ffffffff8108e537>] __run_hrtimer+0x77/0x1d0 [<ffffffff8110ceb0>] ? watchdog_cleanup+0x10/0x10 [<ffffffff8108ed3f>] hrtimer_interrupt+0xef/0x230 [<ffffffff81043087>] local_apic_timer_interrupt+0x37/0x60 [<ffffffff8172887f>] smp_apic_timer_interrupt+0x3f/0x60 [<ffffffff8172721d>] apic_timer_interrupt+0x6d/0x80 <EOI> [<ffffffff8171da2c>] ? _raw_spin_lock+0x1c/0x50 [<ffffffff811d02ce>] shrink_dentry_list+0x4e/0xe0 [<ffffffff811d10f8>] shrink_dcache_parent+0x28/0x70 [<ffffffff81224826>] proc_flush_task+0xb6/0x1b0 [<ffffffff81068540>] release_task+0x30/0x440 [<ffffffff8109e1b1>] ? thread_group_cputime_adjusted+0x41/0x50 [<ffffffff8106922f>] wait_consider_task+0x8df/0xb20 [<ffffffff81069570>] do_wait+0x100/0x240 [<ffffffff8106a6a4>] SyS_wait4+0x64/0xe0 [<ffffffff810682a0>] ? task_stopped_code+0x60/0x60 [<ffffffff817266bf>] tracesys+0xe1/0xe6 Some machines are able to reliably reproduce this soft lockup using the following script. " #!/bin/bash mkdir -p testdir cd testdir while true; do if ! (exec >xx1 2>xx2 ; rm -f xx*; host www.google.com); then echo failed; fi ; done & while true; do ls -lR /proc >& /dev/null; done & while true; do lsof > /dev/null; done & while true; do ls -H >& /dev/null; done & wait " The following changes to dcache have been tested to resolve the issue. https://lkml.org/lkml/2014/5/4/7 even though the original stack trace differs, but still ends in shrink_dentry_list. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1354157/+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