No description
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Yihang Li e368d38cb9 scsi: hisi_sas: Exit suspend state when usage count is greater than 0
When the current status of the host controller is suspended, enabling a
local PHY just after disabling all local PHYs in expander environment, a
hang as follows occurs:

[  486.854655] INFO: task kworker/u256:1:899 blocked for more than 120 seconds.
[  486.862207]       Not tainted 6.1.0-rc4+ #1
[  486.870545] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  486.878893] task:kworker/u256:1  state:D stack:0     pid:899   ppid:2      flags:0x00000008
[  486.887745] Workqueue: 0000:74:02.0_disco_q sas_discover_domain [libsas]
[  486.894704] Call trace:
[  486.897400]  __switch_to+0xf0/0x170
[  486.901146]  __schedule+0x3e4/0x1160
[  486.904970]  schedule+0x64/0x104
[  486.908442]  rpm_resume+0x158/0x6a0
[  486.912163]  __pm_runtime_resume+0x5c/0x84
[  486.916489]  smp_execute_task_sg+0x1f8/0x264 [libsas]
[  486.921773]  sas_discover_expander.part.0+0xbc/0x720 [libsas]
[  486.927750]  sas_discover_root_expander+0x90/0x154 [libsas]
[  486.933552]  sas_discover_domain+0x444/0x6d0 [libsas]
[  486.938826]  process_one_work+0x1e0/0x450
[  486.943057]  worker_thread+0x150/0x44c
[  486.947015]  kthread+0x114/0x120
[  486.950447]  ret_from_fork+0x10/0x20
[  486.954292] INFO: task kworker/u256:2:1780 blocked for more than 120 seconds.
[  486.961637]       Not tainted 6.1.0-rc4+ #1
[  486.966087] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  486.974356] task:kworker/u256:2  state:D stack:0     pid:1780  ppid:2      flags:0x00000208
[  486.983141] Workqueue: 0000:74:02.0_event_q sas_port_event_worker [libsas]
[  486.990252] Call trace:
[  486.992930]  __switch_to+0xf0/0x170
[  486.996645]  __schedule+0x3e4/0x1160
[  487.000439]  schedule+0x64/0x104
[  487.003886]  schedule_timeout+0x17c/0x1c0
[  487.008102]  wait_for_completion+0x7c/0x160
[  487.012488]  __flush_workqueue+0x104/0x3e0
[  487.016782]  sas_porte_bytes_dmaed+0x414/0x454 [libsas]
[  487.022203]  sas_port_event_worker+0x38/0x60 [libsas]
[  487.027449]  process_one_work+0x1e0/0x450
[  487.031645]  worker_thread+0x150/0x44c
[  487.035594]  kthread+0x114/0x120
[  487.039017]  ret_from_fork+0x10/0x20
[  487.042828] INFO: task bash:11488 blocked for more than 121 seconds.
[  487.049366]       Not tainted 6.1.0-rc4+ #1
[  487.053746] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  487.061953] task:bash            state:D stack:0     pid:11488 ppid:10977  flags:0x00000204
[  487.070698] Call trace:
[  487.073355]  __switch_to+0xf0/0x170
[  487.077050]  __schedule+0x3e4/0x1160
[  487.080833]  schedule+0x64/0x104
[  487.084270]  schedule_timeout+0x17c/0x1c0
[  487.088474]  wait_for_completion+0x7c/0x160
[  487.092851]  __flush_workqueue+0x104/0x3e0
[  487.097137]  drain_workqueue+0xb8/0x160
[  487.101159]  __sas_drain_work+0x50/0x90 [libsas]
[  487.105963]  sas_suspend_ha+0x64/0xd4 [libsas]
[  487.110590]  suspend_v3_hw+0x198/0x1e8 [hisi_sas_v3_hw]
[  487.115989]  pci_pm_runtime_suspend+0x5c/0x1d0
[  487.120606]  __rpm_callback+0x50/0x150
[  487.124535]  rpm_callback+0x74/0x80
[  487.128204]  rpm_suspend+0x110/0x640
[  487.131955]  rpm_idle+0x1f4/0x2d0
[  487.135447]  __pm_runtime_idle+0x58/0x94
[  487.139538]  queue_phy_enable+0xcc/0xf0 [libsas]
[  487.144330]  store_sas_phy_enable+0x74/0x100
[  487.148770]  dev_attr_store+0x20/0x34
[  487.152606]  sysfs_kf_write+0x4c/0x5c
[  487.156437]  kernfs_fop_write_iter+0x120/0x1b0
[  487.161049]  vfs_write+0x2d0/0x36c
[  487.164625]  ksys_write+0x70/0x100
[  487.168194]  __arm64_sys_write+0x24/0x30
[  487.172280]  invoke_syscall+0x50/0x120
[  487.176186]  el0_svc_common.constprop.0+0x168/0x190
[  487.181214]  do_el0_svc+0x34/0xc0
[  487.184680]  el0_svc+0x2c/0xb4
[  487.187879]  el0t_64_sync_handler+0xb8/0xbc
[  487.192205]  el0t_64_sync+0x19c/0x1a0

We find that when all local PHYs are disabled, all the devices will be
removed, the ->runtime_suspend() callback suspend_v3_hw() directly execute
since the controller usage count drop to 0. On the other side, the first
local PHY is enabled through the sysfs interface, and ensures that function
phy_up_v3_hw() is completed due to suspend_v3_hw()->
interrupt_disable_v3_hw(). In the expander scenario,
sas_discover_root_expander() is executed in event work
DISCE_DISCOVER_DOMAIN, which will increases the controller usage count and
carry out a resume and sends SMPIO, it cannot be completed because the
runtime PM status of the controller is RPM_SUSPENDING. At the same time,
the ->runtime_suspend() callback suspend_v3_hw() also cannot complete the
process because of drain libsas event queue in sas_suspend_ha(), so hung
occurs.

           (thread 1)                   |        (thread 2)
...                                     |
rpm_idle()                              |
 ...                                    |
 __update_runtime_status(RPM_SUSPENDING)|
  ...                                   | ...
  suspend_v3_hw()                       | smp_execute_task_sg()
   ...                                  |  ...
   interrupt_disable_v3_hw()            |  pm_runtime_get_sync()
                                        |   ...
   ...                                  |   rpm_resume() //RPM_SUSPENDING
                                        |
    __sas_drain_work()                  |

To fix this, check if the current runtime PM status of the controller
allows to be suspended continue after interrupt_disable_v3_hw(), return
immediately if not.

Signed-off-by: Yihang Li <liyihang9@huawei.com>
Signed-off-by: Xiang Chen <chenxiang66@hislicon.com>
Link: https://lore.kernel.org/r/1679283265-115066-5-git-send-email-chenxiang66@hisilicon.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
History 2023-04-02 21:57:35 -04:00
arch cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
block block-6.3-2023-03-03 2023-03-03 10:21:39 -08:00
certs Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
crypto Networking changes for 6.3. 2023-02-21 18:24:12 -08:00
Documentation A small set of updates for x86: 2023-03-05 11:27:48 -08:00
drivers scsi: hisi_sas: Exit suspend state when usage count is greater than 0 2023-04-02 21:57:35 -04:00
fs 17 hotfixes. Eight are for MM and seven are for other parts of the 2023-03-04 13:32:50 -08:00
include cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
init Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
io_uring io_uring-6.3-2023-03-03 2023-03-03 10:25:29 -08:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel A set of updates for the interrupt susbsystem: 2023-03-05 11:19:16 -08:00
lib cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: avoid gcc complaint about pointer casting 2023-03-04 14:03:27 -08:00
net nfsd-6.3 fixes: 2023-03-01 11:03:44 -08:00
rust Rust fixes for 6.3-rc1 2023-03-03 14:51:15 -08:00
samples LoongArch changes for v6.3 2023-03-01 09:27:00 -08:00
scripts Remove Intel compiler support 2023-03-05 10:49:37 -08:00
security capability: just use a 'u64' instead of a 'u32[2]' array 2023-03-01 10:01:22 -08:00
sound sound fixes for 6.3-rc1 2023-03-04 10:53:59 -08:00
tools Changes in this cycle were: 2023-03-02 09:45:34 -08:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM/riscv changes for 6.3 2023-02-15 12:33:28 -05:00
.clang-format cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore .gitignore: ignore *.cover and *.mbx 2023-02-05 18:51:22 +09:00
.mailmap mailmap: map Dikshita Agarwal's old address to his current one 2023-03-02 21:54:24 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Adding Christian Brauner as VFS co-maintainer. 2023-03-05 11:11:52 -08:00
Makefile Linux 6.3-rc1 2023-03-05 14:52:03 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.