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Pavel Tatashin 627f712db6 mm/memory_hotplug: drain per-cpu pages again during memory offline
commit 9683182612214aa5f5e709fad49444b847cd866a upstream.

There is a race during page offline that can lead to infinite loop:
a page never ends up on a buddy list and __offline_pages() keeps
retrying infinitely or until a termination signal is received.

Thread#1 - a new process:

load_elf_binary
 begin_new_exec
  exec_mmap
   mmput
    exit_mmap
     tlb_finish_mmu
      tlb_flush_mmu
       release_pages
        free_unref_page_list
         free_unref_page_prepare
          set_pcppage_migratetype(page, migratetype);
             // Set page->index migration type below  MIGRATE_PCPTYPES

Thread#2 - hot-removes memory
__offline_pages
  start_isolate_page_range
    set_migratetype_isolate
      set_pageblock_migratetype(page, MIGRATE_ISOLATE);
        Set migration type to MIGRATE_ISOLATE-> set
        drain_all_pages(zone);
             // drain per-cpu page lists to buddy allocator.

Thread#1 - continue
         free_unref_page_commit
           migratetype = get_pcppage_migratetype(page);
              // get old migration type
           list_add(&page->lru, &pcp->lists[migratetype]);
              // add new page to already drained pcp list

Thread#2
Never drains pcp again, and therefore gets stuck in the loop.

The fix is to try to drain per-cpu lists again after
check_pages_isolated_cb() fails.

Fixes: c52e75935f8d ("mm: remove extra drain pages on pcp list")
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200903140032.380431-1-pasha.tatashin@soleen.com
Link: https://lkml.kernel.org/r/20200904151448.100489-2-pasha.tatashin@soleen.com
Link: http://lkml.kernel.org/r/20200904070235.GA15277@dhcp22.suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:36:22 +08:00
Documentation affs: fix basic permission bits to actually work 2021-03-16 16:35:42 +08:00
LICENSES Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
arch powerpc/dma: Fix dma_map_ops::get_required_mask 2021-03-16 16:36:22 +08:00
block block: only call sched requeue_request() for scheduled requests 2021-03-16 16:36:14 +08:00
certs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
crypto crypto: af_alg - Work around empty control messages without MSG_MORE 2021-03-16 16:35:14 +08:00
drivers dm/dax: Fix table reference counts 2021-03-16 16:36:22 +08:00
fs f2fs: Return EOF on unaligned end of file DIO read 2021-03-16 16:36:14 +08:00
include KVM: MIPS: Change the definition of kvm type 2021-03-16 16:36:15 +08:00
init x86: Fix early boot crash on gcc-10, third try 2021-03-16 16:28:02 +08:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2021-03-16 16:27:51 +08:00
kernel gcov: add support for GCC 10.1 2021-03-16 16:36:10 +08:00
lib kobject: Restore old behaviour of kobject_del(NULL) 2021-03-16 16:36:04 +08:00
mm mm/memory_hotplug: drain per-cpu pages again during memory offline 2021-03-16 16:36:22 +08:00
net SUNRPC: stop printk reading past end of string 2021-03-16 16:36:13 +08:00
package config/arm64: OPEN CONFIG_PSI and phytium configs 2021-03-16 11:02:59 +08:00
samples bpf: Fix fds_example SIGSEGV error 2021-03-16 16:33:24 +08:00
scripts checkpatch: fix the usage of capture group ( ... ) 2021-03-16 16:35:45 +08:00
security Smack: prevent underflow in smk_set_cipso() 2021-03-16 16:33:40 +08:00
sound ALSA: hda/realtek - The Mic on a RedmiBook doesn't work 2021-03-16 16:36:20 +08:00
tools selftests/vm: fix display of page size in map_hugetlb 2021-03-16 16:36:22 +08:00
usr Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
virt KVM: fix memory leak in kvm_io_bus_unregister_dev() 2021-03-16 16:36:07 +08:00
.clang-format Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
.cocciconfig Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
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.gitattributes Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
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CREDITS Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Kbuild Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Kconfig Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
MAINTAINERS Documentation/llvm: add documentation on building w/ Clang/LLVM 2021-03-16 16:34:24 +08:00
Makefile kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables 2021-03-16 16:35:20 +08:00
README Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
README.md Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
backport_remove_lists.txt Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
tools_key.pub Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00

README.md

Tencent Linux Kernel 4.0