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Vaibhav Jain cc74896531 powerpc/mm: Add cond_resched() while removing hpte mappings
[ Upstream commit a5d6a3e73a ]

While removing large number of mappings from hash page tables for
large memory systems as soft-lockup is reported because of the time
spent inside htap_remove_mapping() like one below:

 watchdog: BUG: soft lockup - CPU#8 stuck for 23s!
 <snip>
 NIP plpar_hcall+0x38/0x58
 LR  pSeries_lpar_hpte_invalidate+0x68/0xb0
 Call Trace:
  0x1fffffffffff000 (unreliable)
  pSeries_lpar_hpte_removebolted+0x9c/0x230
  hash__remove_section_mapping+0xec/0x1c0
  remove_section_mapping+0x28/0x3c
  arch_remove_memory+0xfc/0x150
  devm_memremap_pages_release+0x180/0x2f0
  devm_action_release+0x30/0x50
  release_nodes+0x28c/0x300
  device_release_driver_internal+0x16c/0x280
  unbind_store+0x124/0x170
  drv_attr_store+0x44/0x60
  sysfs_kf_write+0x64/0x90
  kernfs_fop_write+0x1b0/0x290
  __vfs_write+0x3c/0x70
  vfs_write+0xd4/0x270
  ksys_write+0xdc/0x130
  system_call+0x5c/0x70

Fix this by adding a cond_resched() to the loop in
htap_remove_mapping() that issues hcall to remove hpte mapping. The
call to cond_resched() is issued every HZ jiffies which should prevent
the soft-lockup from being reported.

Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210404163148.321346-1-vaibhav@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19 10:12:56 +02:00
arch powerpc/mm: Add cond_resched() while removing hpte mappings 2021-05-19 10:12:56 +02:00
block block: return -EBUSY when there are open partitions in blkdev_reread_part 2021-04-28 13:39:59 +02:00
certs certs: Fix blacklist flag type confusion 2021-03-04 11:37:59 +01:00
crypto async_xor: increase src_offs when dropping destination page 2021-05-14 09:49:59 +02:00
Documentation media: docs: Fix data organization of MEDIA_BUS_FMT_RGB101010_1X30 2021-05-14 09:50:23 +02:00
drivers iwlwifi: pcie: make cfg vs. trans_cfg more robust 2021-05-19 10:12:56 +02:00
fs cuse: prevent clone 2021-05-19 10:12:56 +02:00
include i2c: Add I2C_AQ_NO_REP_START adapter quirk 2021-05-19 10:12:54 +02:00
init seccomp: Fix CONFIG tests for Seccomp_filters 2021-05-14 09:50:24 +02:00
ipc ipc: adjust proc_ipc_sem_dointvec definition to match prototype 2020-09-05 12:14:29 -07:00
kernel smp: Fix smp_call_function_single_async prototype 2021-05-14 09:50:46 +02:00
lib bug: Remove redundant condition check in report_bug 2021-05-14 09:50:32 +02:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm/memory-failure: unnecessary amount of unmapping 2021-05-14 09:50:45 +02:00
net mac80211: clear the beacon's CRC after channel switch 2021-05-19 10:12:55 +02:00
samples kfifo: fix ternary sign extension bugs 2021-05-14 09:50:45 +02:00
scripts kasan: fix hwasan build for gcc 2021-04-28 13:40:02 +02:00
security KEYS: trusted: Fix memory leak on object td 2021-05-19 10:12:50 +02:00
sound ASoC: rt5670: Add a quirk for the Dell Venue 10 Pro 5055 2021-05-19 10:12:54 +02:00
tools selftests/powerpc: Fix L1D flushing tests for Power10 2021-05-19 10:12:54 +02:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt kvm: Cap halt polling at kvm->max_halt_poll_ns 2021-05-19 10:12:51 +02:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
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.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: docs: ignore sphinx_*/ directories 2020-09-10 10:44:31 -06:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: move the staging subsystem to lists.linux.dev 2021-03-25 09:04:18 +01:00
Makefile Linux 5.10.37 2021-05-14 09:50:46 +02:00
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.