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David Hildenbrand ed9c101e71 mm/shuffle: don't move pages between zones and don't read garbage memmaps
[ Upstream commit 4a93025cbe4a0b19d1a25a2d763a3d2018bad0d9 ]

Especially with memory hotplug, we can have offline sections (with a
garbage memmap) and overlapping zones.  We have to make sure to only touch
initialized memmaps (online sections managed by the buddy) and that the
zone matches, to not move pages between zones.

To test if this can actually happen, I added a simple

	BUG_ON(page_zone(page_i) != page_zone(page_j));

right before the swap.  When hotplugging a 256M DIMM to a 4G x86-64 VM and
onlining the first memory block "online_movable" and the second memory
block "online_kernel", it will trigger the BUG, as both zones (NORMAL and
MOVABLE) overlap.

This might result in all kinds of weird situations (e.g., double
allocations, list corruptions, unmovable allocations ending up in the
movable zone).

Fixes: e900a918b098 ("mm: shuffle initial free memory to improve memory-side-cache utilization")
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: <stable@vger.kernel.org>	[5.2+]
Link: http://lkml.kernel.org/r/20200624094741.9918-2-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:34:57 +08:00
Documentation kbuild: support LLVM=1 to switch the default tools to Clang/LLVM 2021-03-16 16:34:25 +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 s390/numa: set node distance to LOCAL_DISTANCE 2021-03-16 16:34:56 +08:00
block iocost: Fix check condition of iocg abs_vdebt 2021-03-16 16:33:18 +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: algif_aead - fix uninitialized ctx->init 2021-03-16 16:34:22 +08:00
drivers drm/xen-front: Fix misused IS_ERR_OR_NULL checks 2021-03-16 16:34:56 +08:00
fs btrfs: only commit delayed items at fsync if we are logging a directory 2021-03-16 16:34:56 +08:00
include efi: provide empty efi_enter_virtual_mode implementation 2021-03-16 16:34:54 +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 sched/uclamp: Fix a deadlock when enabling uclamp static key 2021-03-16 16:34:55 +08:00
lib test_kmod: avoid potential double free in trigger_config_run_type() 2021-03-16 16:34:21 +08:00
mm mm/shuffle: don't move pages between zones and don't read garbage memmaps 2021-03-16 16:34:57 +08:00
net net/sched: act_ct: Fix skb double-free in tcf_ct_handle_fragments() error flow 2021-03-16 16:34:44 +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 kconfig: qconf: fix signal connection to invalid slots 2021-03-16 16:34:39 +08:00
security Smack: prevent underflow in smk_set_cipso() 2021-03-16 16:33:40 +08:00
sound ALSA: hda: Add support for Loongson 7A1000 controller 2021-03-16 16:34:50 +08:00
tools selftests/powerpc: Purge extra count_pmc() calls of ebb selftests 2021-03-16 16:34:49 +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: arm64: Only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is not set 2021-03-16 16:34:42 +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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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: support LLVM=1 to switch the default tools to Clang/LLVM 2021-03-16 16:34:25 +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

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Tencent Linux Kernel 4.0