| 2017-11-14 18:03:16 |
dann frazier |
bug |
|
|
added bug |
| 2017-11-14 18:30:06 |
Ubuntu Kernel Bot |
linux (Ubuntu): status |
New |
Incomplete |
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| 2017-11-14 20:14:52 |
dann frazier |
nominated for series |
|
Ubuntu Artful |
|
| 2017-11-14 20:14:52 |
dann frazier |
bug task added |
|
linux (Ubuntu Artful) |
|
| 2017-11-14 20:14:58 |
dann frazier |
linux (Ubuntu): status |
Incomplete |
Confirmed |
|
| 2017-11-14 20:15:00 |
dann frazier |
linux (Ubuntu Artful): status |
New |
Confirmed |
|
| 2017-11-14 20:15:11 |
dann frazier |
linux (Ubuntu): assignee |
|
dann frazier (dannf) |
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| 2017-11-14 20:15:13 |
dann frazier |
linux (Ubuntu Artful): assignee |
|
dann frazier (dannf) |
|
| 2018-01-04 23:37:11 |
dann frazier |
description |
[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.
[Test Case]
$ stress-ng --kill 0 -t 300 -v
You'll see the console fill with messages like:
[ 2534.423119] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 2534.428606] 192-...: (1 ticks this GP) idle=b6e/140000000000000/0 softirq=578/578 fqs=6770
[ 2534.437029] (detected by 0, t=15005 jiffies, g=1479, c=1478, q=473)
[ 2714.623691] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 2714.629181] 192-...: (1 ticks this GP) idle=b6e/140000000000000/0 softirq=578/578 fqs=12819
[ 2714.637692] (detected by 116, t=60058 jiffies, g=1479, c=1478, q=1736)
[ 2747.216955] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [kworker/0:5:1464]
[ 2775.399061] watchdog: BUG: soft lockup - CPU#13 stuck for 123s! [systemd-network:2936]
[Regression Risk]
TBD |
[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 0 -t 300 -v
You'll see the console fill with messages like:
[ 2534.423119] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 2534.428606] 192-...: (1 ticks this GP) idle=b6e/140000000000000/0 softirq=578/578 fqs=6770
[ 2534.437029] (detected by 0, t=15005 jiffies, g=1479, c=1478, q=473)
[ 2714.623691] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 2714.629181] 192-...: (1 ticks this GP) idle=b6e/140000000000000/0 softirq=578/578 fqs=12819
[ 2714.637692] (detected by 116, t=60058 jiffies, g=1479, c=1478, q=1736)
[ 2747.216955] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [kworker/0:5:1464]
[ 2775.399061] watchdog: BUG: soft lockup - CPU#13 stuck for 123s! [systemd-network:2936]
[Regression Risk]
TBD |
|
| 2018-01-05 01:19:55 |
dann frazier |
description |
[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 0 -t 300 -v
You'll see the console fill with messages like:
[ 2534.423119] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 2534.428606] 192-...: (1 ticks this GP) idle=b6e/140000000000000/0 softirq=578/578 fqs=6770
[ 2534.437029] (detected by 0, t=15005 jiffies, g=1479, c=1478, q=473)
[ 2714.623691] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 2714.629181] 192-...: (1 ticks this GP) idle=b6e/140000000000000/0 softirq=578/578 fqs=12819
[ 2714.637692] (detected by 116, t=60058 jiffies, g=1479, c=1478, q=1736)
[ 2747.216955] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [kworker/0:5:1464]
[ 2775.399061] watchdog: BUG: soft lockup - CPU#13 stuck for 123s! [systemd-network:2936]
[Regression Risk]
TBD |
[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 0 -t 300 -v
You'll see the console fill with messages like:
[ 2534.423119] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 2534.428606] 192-...: (1 ticks this GP) idle=b6e/140000000000000/0 softirq=578/578 fqs=6770
[ 2534.437029] (detected by 0, t=15005 jiffies, g=1479, c=1478, q=473)
[ 2714.623691] INFO: rcu_sched detected stalls on CPUs/tasks:
[ 2714.629181] 192-...: (1 ticks this GP) idle=b6e/140000000000000/0 softirq=578/578 fqs=12819
[ 2714.637692] (detected by 116, t=60058 jiffies, g=1479, c=1478, q=1736)
[ 2747.216955] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [kworker/0:5:1464]
[ 2775.399061] watchdog: BUG: soft lockup - CPU#13 stuck for 123s! [systemd-network:2936]
[Regression Risk]
The proposed fix for this comprises clean cherry-picks from the v4.15 merge window. The code modified for this fix is restricted to x86 & arm64, as they are the only Ubuntu architectures that define ARCH_USE_QUEUED_LOCKS. Fix verified on a 228 CPU arm64 (ThunderX2) server and regression tested on a 128-cpu x86 system using stress-ng and locktorture. |
|
| 2018-01-10 16:13:03 |
Seth Forshee |
linux (Ubuntu): status |
Confirmed |
Fix Committed |
|
| 2018-02-04 01:15:36 |
Khaled El Mously |
linux (Ubuntu Artful): status |
Confirmed |
Fix Committed |
|
| 2018-02-14 09:37:43 |
Kleber Sacilotto de Souza |
tags |
|
verification-needed-artful |
|
| 2018-02-14 20:16:41 |
dann frazier |
tags |
verification-needed-artful |
verification-done-artful |
|
| 2018-02-21 18:56:18 |
Launchpad Janitor |
linux (Ubuntu Artful): status |
Fix Committed |
Fix Released |
|
| 2018-02-21 18:56:18 |
Launchpad Janitor |
cve linked |
|
2017-15115 |
|
| 2018-02-21 18:56:18 |
Launchpad Janitor |
cve linked |
|
2017-17712 |
|
| 2018-02-21 18:56:18 |
Launchpad Janitor |
cve linked |
|
2017-5715 |
|
| 2018-02-21 18:56:18 |
Launchpad Janitor |
cve linked |
|
2017-5753 |
|
| 2018-02-21 18:56:18 |
Launchpad Janitor |
cve linked |
|
2017-5754 |
|
| 2018-02-21 18:56:18 |
Launchpad Janitor |
cve linked |
|
2017-8824 |
|
| 2019-10-03 08:16:41 |
Po-Hsu Lin |
linux (Ubuntu): status |
Fix Committed |
Fix Released |
|
