https://github.com/torvalds/linux
Revision d9770fcc1c0c5b3e77dfac83b47defa3981fa7cd authored by Hugh Dickins on 07 July 2021, 20:08:53 UTC, committed by Linus Torvalds on 11 July 2021, 22:05:15 UTC
The kernel recovers in due course from missing Mlocked pages: but there was no point in calling page_mlock() (formerly known as try_to_munlock()) on a THP, because nothing got done even when it was found to be mapped in another VM_LOCKED vma. It's true that we need to be careful: Mlocked accounting of pte-mapped THPs is too difficult (so consistently avoided); but Mlocked accounting of only-pmd-mapped THPs is supposed to work, even when multiple mappings are mlocked and munlocked or munmapped. Refine the tests. There is already a VM_BUG_ON_PAGE(PageDoubleMap) in page_mlock(), so page_mlock_one() does not even have to worry about that complication. (I said the kernel recovers: but would page reclaim be likely to split THP before rediscovering that it's VM_LOCKED? I've not followed that up) Fixes: 9a73f61bdb8a ("thp, mlock: do not mlock PTE-mapped file huge pages") Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Link: https://lore.kernel.org/lkml/cfa154c-d595-406-eb7d-eb9df730f944@google.com/ Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Alistair Popple <apopple@nvidia.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Tip revision: d9770fcc1c0c5b3e77dfac83b47defa3981fa7cd authored by Hugh Dickins on 07 July 2021, 20:08:53 UTC
mm/rmap: fix old bug: munlocking THP missed other mlocks
mm/rmap: fix old bug: munlocking THP missed other mlocks
Tip revision: d9770fc
File | Mode | Size |
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arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | -rw-r--r-- | 16.6 KB |
.cocciconfig | -rw-r--r-- | 59 bytes |
.get_maintainer.ignore | -rw-r--r-- | 71 bytes |
.gitattributes | -rw-r--r-- | 62 bytes |
.gitignore | -rw-r--r-- | 1.9 KB |
.mailmap | -rw-r--r-- | 19.7 KB |
COPYING | -rw-r--r-- | 496 bytes |
CREDITS | -rw-r--r-- | 98.6 KB |
Kbuild | -rw-r--r-- | 1.3 KB |
Kconfig | -rw-r--r-- | 555 bytes |
MAINTAINERS | -rw-r--r-- | 596.6 KB |
Makefile | -rw-r--r-- | 63.5 KB |
README | -rw-r--r-- | 727 bytes |
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