linux/include
Barry Song 259043e3b7 mm: zswap: fix zswap_never_enabled() for CONFIG_ZSWAP==N
If CONFIG_ZSWAP is set to N, it means zswap cannot be enabled. 
zswap_never_enabled() should return true.

The only effect of this issue is that with Barry's latest large folio
swapin patches for zram ("mm: support mTHP swap-in for zRAM-like
swapfile"), we will always fallback to order-0 swapin, even mistakenly
when !CONFIG_ZSWAP.

Basically this bug makes Barry's in progress patches not work at all.

The API was created to inform the mm core that zswap has never been
enabled, allowing the mm core to perform mTHP swap-in.  This is a
transitional solution until zswap supports mTHP.  If zswap has been
enabled, performing mTHP swap-in will result in corrupted data.  You
may find the answer in the mTHP swap-in series:

https://lore.kernel.org/linux-mm/CAJD7tkZ4FQr6HZpduOdvmqgg_-whuZYE-Bz5O2t6yzw6Yg+v1A@mail.gmail.com/

Link: https://lkml.kernel.org/r/20240629232231.42394-1-21cnbao@gmail.com
Fixes: 0300e17d67c3 ("mm: zswap: add zswap_never_enabled()")
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Chris Li <chrisl@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-10 12:14:55 -07:00
..
acpi ACPI: EC: Evaluate orphan _REG under EC device 2024-06-13 11:28:54 +02:00
asm-generic syscalls: mmap(): use unsigned offset type consistently 2024-06-25 15:57:38 +02:00
clocksource
crypto This push fixes a bug in the new ecc P521 code as well as a buggy 2024-05-20 08:47:54 -07:00
drm Short summary of fixes pull: 2024-05-27 13:47:14 +10:00
dt-bindings dt-bindings: net: dp8386x: Add MIT license along with GPL-2.0 2024-06-07 12:16:22 +01:00
keys
kunit
kvm
linux mm: zswap: fix zswap_never_enabled() for CONFIG_ZSWAP==N 2024-07-10 12:14:55 -07:00
math-emu
media
memory
misc
net netfilter pull request 24-06-27 2024-06-27 13:00:50 +02:00
pcmcia
ras mm/memory-failure: remove MF_MSG_SLAB 2024-07-03 19:30:10 -07:00
rdma The usual shower of singleton fixes and minor series all over MM, 2024-05-19 09:21:03 -07:00
rv
scsi scsi: core: Introduce the BLIST_SKIP_IO_HINTS flag 2024-06-13 21:03:13 -04:00
soc I'm actually surprised this time. There aren't any new Qualcomm SoC clk 2024-05-18 12:48:37 -07:00
sound ALSA: dmaengine: Synchronize dma channel after drop() 2024-06-11 17:13:31 +01:00
target
trace mm: remove CONFIG_MEMCG_KMEM 2024-07-10 12:14:54 -07:00
uapi syscalls: fix compat_sys_io_pgetevents_time64 usage 2024-06-25 15:57:20 +02:00
ufs
vdso
video
xen