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Kefeng Wang 34d7cf637c mm: don't try THP alignment for FS without get_unmapped_area
Commit ed48e87c7d ("thp: add thp_get_unmapped_area_vmflags()") changes
thp_get_unmapped_area() to thp_get_unmapped_area_vmflags() in
__get_unmapped_area(), which doesn't initialize local get_area for
anonymous mappings.  This leads to us always trying THP alignment even for
file_operations which have a NULL ->get_unmapped_area() callback.

Since commit efa7df3e3b ("mm: align larger anonymous mappings on THP
boundaries") we only want to enable THP alignment for anonymous mappings,
so add a !file check to avoid attempting THP alignment for file mappings.

Found issue by code inspection.  THP alignment is used for easy or more
pmd mappings, from vma side.  This may cause unnecessary VMA fragmentation
and potentially worse performance on filesystems that do not actually
support THPs and thus cannot benefit from the alignment.

Link: https://lkml.kernel.org/r/20241206070345.2526501-1-wangkefeng.wang@huawei.com
Fixes: ed48e87c7d ("thp: add thp_get_unmapped_area_vmflags()")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-12-30 17:59:06 -08:00
arch KVM x86 fixes for 6.13: 2024-12-22 12:16:41 -08:00
block block: avoid to reuse hctx not removed from cpuhp callback list 2024-12-18 07:25:37 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: rsassa-pkcs1 - Copy source data for SG list 2024-12-10 13:34:05 +08:00
Documentation Devicetree fixes for 6.13, part 1: 2024-12-22 08:40:23 -08:00
drivers Devicetree fixes for 6.13, part 1: 2024-12-22 08:40:23 -08:00
fs 25 hotfixes. 16 are cc:stable. 19 are MM and 6 are non-MM. 2024-12-21 15:31:56 -08:00
include mm: reinstate ability to map write-sealed memfd mappings read-only 2024-12-30 17:59:06 -08:00
init - The series "resource: A couple of cleanups" from Andy Shevchenko 2024-11-25 16:09:48 -08:00
io_uring io_uring: check if iowq is killed before queuing 2024-12-19 13:31:53 -07:00
ipc - The series "resource: A couple of cleanups" from Andy Shevchenko 2024-11-25 16:09:48 -08:00
kernel 25 hotfixes. 16 are cc:stable. 19 are MM and 6 are non-MM. 2024-12-21 15:31:56 -08:00
lib alloc_tag: fix module allocation tags populated area calculation 2024-12-18 19:04:46 -08:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm mm: don't try THP alignment for FS without get_unmapped_area 2024-12-30 17:59:06 -08:00
net BPF fixes: 2024-12-21 11:07:19 -08:00
rust Including fixes from can and netfilter. 2024-12-19 09:19:11 -08:00
samples BPF fixes: 2024-12-06 15:07:48 -08:00
scripts Kbuild fixes for v6.13 (2nd) 2024-12-21 11:24:32 -08:00
security selinux/stable-6.13 PR 20241217 2024-12-18 12:10:15 -08:00
sound soc: fixes for 6.13 2024-12-16 10:10:53 -08:00
tools selftests/memfd: add test for mapping write-sealed memfd read-only 2024-12-30 17:59:06 -08:00
usr kbuild: Drop support for include/asm-<arch> in headers_check.pl 2024-12-21 11:43:17 +09:00
virt VFIO updates for v6.13 2024-11-27 12:57:03 -08:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.clippy.toml rust: enable Clippy's check-private-items 2024-10-07 21:39:57 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Kbuild updates for v6.13 2024-11-30 13:41:50 -08:00
.mailmap mailmap: add entry for Ying Huang 2024-12-18 19:04:41 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS cgroup: Changes for v6.13 2024-11-20 09:54:49 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS drm fixes for 6.13-rc4 2024-12-20 10:17:53 -08:00
Makefile Linux 6.13-rc4 2024-12-22 13:22:21 -08:00
README README: Fix spelling 2024-03-18 03:36:32 -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 reStructuredText 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.