<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/init/Kconfig, branch v5.12-rc8</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge branch 'akpm' (patches from Andrew)</title>
<updated>2021-03-14T19:23:34+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-03-14T19:23:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=50eb842fe517b2765b7748c3016082b484a6dbb8'/>
<id>50eb842fe517b2765b7748c3016082b484a6dbb8</id>
<content type='text'>
Merge misc fixes from Andrew Morton:
 "28 patches.

  Subsystems affected by this series: mm (memblock, pagealloc, hugetlb,
  highmem, kfence, oom-kill, madvise, kasan, userfaultfd, memcg, and
  zram), core-kernel, kconfig, fork, binfmt, MAINTAINERS, kbuild, and
  ia64"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (28 commits)
  zram: fix broken page writeback
  zram: fix return value on writeback_store
  mm/memcg: set memcg when splitting page
  mm/memcg: rename mem_cgroup_split_huge_fixup to split_page_memcg and add nr_pages argument
  ia64: fix ptrace(PTRACE_SYSCALL_INFO_EXIT) sign
  ia64: fix ia64_syscall_get_set_arguments() for break-based syscalls
  mm/userfaultfd: fix memory corruption due to writeprotect
  kasan: fix KASAN_STACK dependency for HW_TAGS
  kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOC
  mm/madvise: replace ptrace attach requirement for process_madvise
  include/linux/sched/mm.h: use rcu_dereference in in_vfork()
  kfence: fix reports if constant function prefixes exist
  kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocations
  kfence: fix printk format for ptrdiff_t
  linux/compiler-clang.h: define HAVE_BUILTIN_BSWAP*
  MAINTAINERS: exclude uapi directories in API/ABI section
  binfmt_misc: fix possible deadlock in bm_register_write
  mm/highmem.c: fix zero_user_segments() with start &gt; end
  hugetlb: do early cow when page pinned on src mm
  mm: use is_cow_mapping() across tree where proper
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge misc fixes from Andrew Morton:
 "28 patches.

  Subsystems affected by this series: mm (memblock, pagealloc, hugetlb,
  highmem, kfence, oom-kill, madvise, kasan, userfaultfd, memcg, and
  zram), core-kernel, kconfig, fork, binfmt, MAINTAINERS, kbuild, and
  ia64"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (28 commits)
  zram: fix broken page writeback
  zram: fix return value on writeback_store
  mm/memcg: set memcg when splitting page
  mm/memcg: rename mem_cgroup_split_huge_fixup to split_page_memcg and add nr_pages argument
  ia64: fix ptrace(PTRACE_SYSCALL_INFO_EXIT) sign
  ia64: fix ia64_syscall_get_set_arguments() for break-based syscalls
  mm/userfaultfd: fix memory corruption due to writeprotect
  kasan: fix KASAN_STACK dependency for HW_TAGS
  kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOC
  mm/madvise: replace ptrace attach requirement for process_madvise
  include/linux/sched/mm.h: use rcu_dereference in in_vfork()
  kfence: fix reports if constant function prefixes exist
  kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocations
  kfence: fix printk format for ptrdiff_t
  linux/compiler-clang.h: define HAVE_BUILTIN_BSWAP*
  MAINTAINERS: exclude uapi directories in API/ABI section
  binfmt_misc: fix possible deadlock in bm_register_write
  mm/highmem.c: fix zero_user_segments() with start &gt; end
  hugetlb: do early cow when page pinned on src mm
  mm: use is_cow_mapping() across tree where proper
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>init/Kconfig: make COMPILE_TEST depend on HAS_IOMEM</title>
<updated>2021-03-13T19:27:30+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2021-03-13T05:07:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ea29b20a828511de3348334e529a3d046a180416'/>
<id>ea29b20a828511de3348334e529a3d046a180416</id>
<content type='text'>
I read the commit log of the following two:

- bc083a64b6c0 ("init/Kconfig: make COMPILE_TEST depend on !UML")
- 334ef6ed06fa ("init/Kconfig: make COMPILE_TEST depend on !S390")

Both are talking about HAS_IOMEM dependency missing in many drivers.

So, 'depends on HAS_IOMEM' seems the direct, sensible solution to me.

This does not change the behavior of UML. UML still cannot enable
COMPILE_TEST because it does not provide HAS_IOMEM.

The current dependency for S390 is too strong. Under the condition of
CONFIG_PCI=y, S390 provides HAS_IOMEM, hence can enable COMPILE_TEST.

I also removed the meaningless 'default n'.

Link: https://lkml.kernel.org/r/20210224140809.1067582-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Cc: Arnd Bergmann &lt;arnd@kernel.org&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: KP Singh &lt;kpsingh@google.com&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Terrell &lt;terrelln@fb.com&gt;
Cc: Quentin Perret &lt;qperret@google.com&gt;
Cc: Valentin Schneider &lt;valentin.schneider@arm.com&gt;
Cc: "Enrico Weigelt, metux IT consult" &lt;lkml@metux.net&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
I read the commit log of the following two:

- bc083a64b6c0 ("init/Kconfig: make COMPILE_TEST depend on !UML")
- 334ef6ed06fa ("init/Kconfig: make COMPILE_TEST depend on !S390")

Both are talking about HAS_IOMEM dependency missing in many drivers.

So, 'depends on HAS_IOMEM' seems the direct, sensible solution to me.

This does not change the behavior of UML. UML still cannot enable
COMPILE_TEST because it does not provide HAS_IOMEM.

The current dependency for S390 is too strong. Under the condition of
CONFIG_PCI=y, S390 provides HAS_IOMEM, hence can enable COMPILE_TEST.

I also removed the meaningless 'default n'.

Link: https://lkml.kernel.org/r/20210224140809.1067582-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Cc: Arnd Bergmann &lt;arnd@kernel.org&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: KP Singh &lt;kpsingh@google.com&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Nick Terrell &lt;terrelln@fb.com&gt;
Cc: Quentin Perret &lt;qperret@google.com&gt;
Cc: Valentin Schneider &lt;valentin.schneider@arm.com&gt;
Cc: "Enrico Weigelt, metux IT consult" &lt;lkml@metux.net&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kbuild: rebuild GCC plugins when the compiler is upgraded</title>
<updated>2021-03-11T05:40:50+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2021-03-04T11:37:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ce6ed1c4c9876c2880f52f18c41ef2a30d070bc5'/>
<id>ce6ed1c4c9876c2880f52f18c41ef2a30d070bc5</id>
<content type='text'>
Linus reported a build error due to the GCC plugin incompatibility
when the compiler is upgraded. [1]

GCC plugins are tied to a particular GCC version. So, they must be
rebuilt when the compiler is upgraded.

This seems to be a long-standing flaw since the initial support of
GCC plugins.

Extend commit 8b59cd81dc5e ("kbuild: ensure full rebuild when the
compiler is updated"), so that GCC plugins are covered by the
compiler upgrade detection.

[1]: https://lore.kernel.org/lkml/CAHk-=wieoN5ttOy7SnsGwZv+Fni3R6m-Ut=oxih6bbZ28G+4dw@mail.gmail.com/

Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Linus reported a build error due to the GCC plugin incompatibility
when the compiler is upgraded. [1]

GCC plugins are tied to a particular GCC version. So, they must be
rebuilt when the compiler is upgraded.

This seems to be a long-standing flaw since the initial support of
GCC plugins.

Extend commit 8b59cd81dc5e ("kbuild: ensure full rebuild when the
compiler is updated"), so that GCC plugins are covered by the
compiler upgrade detection.

[1]: https://lore.kernel.org/lkml/CAHk-=wieoN5ttOy7SnsGwZv+Fni3R6m-Ut=oxih6bbZ28G+4dw@mail.gmail.com/

Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kbuild: fix UNUSED_KSYMS_WHITELIST for Clang LTO</title>
<updated>2021-02-28T06:19:21+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2021-02-26T06:25:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a6aaeb841198016083663ae56c568de4e065d090'/>
<id>a6aaeb841198016083663ae56c568de4e065d090</id>
<content type='text'>
Commit fbe078d397b4 ("kbuild: lto: add a default list of used symbols")
does not work as expected if the .config file has already specified
CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list" before enabling
CONFIG_LTO_CLANG.

So, the user-supplied whitelist and LTO-specific white list must be
independent of each other.

I refactored the shell script so CONFIG_MODVERSIONS and CONFIG_CLANG_LTO
handle whitelists in the same way.

Fixes: fbe078d397b4 ("kbuild: lto: add a default list of used symbols")
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Tested-by: Sedat Dilek &lt;sedat.dilek@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit fbe078d397b4 ("kbuild: lto: add a default list of used symbols")
does not work as expected if the .config file has already specified
CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list" before enabling
CONFIG_LTO_CLANG.

So, the user-supplied whitelist and LTO-specific white list must be
independent of each other.

I refactored the shell script so CONFIG_MODVERSIONS and CONFIG_CLANG_LTO
handle whitelists in the same way.

Fixes: fbe078d397b4 ("kbuild: lto: add a default list of used symbols")
Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Tested-by: Sedat Dilek &lt;sedat.dilek@gmail.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>init/Kconfig: fix a typo in CC_VERSION_TEXT help text</title>
<updated>2021-02-26T17:41:05+00:00</updated>
<author>
<name>Bhaskar Chowdhury</name>
<email>unixbhaskar@gmail.com</email>
</author>
<published>2021-02-26T01:22:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f9c8bc4604c95a7c55293f244f67753f6e96096f'/>
<id>f9c8bc4604c95a7c55293f244f67753f6e96096f</id>
<content type='text'>
s/compier/compiler/

Link: https://lkml.kernel.org/r/20210224223325.29099-1-unixbhaskar@gmail.com
Signed-off-by: Bhaskar Chowdhury &lt;unixbhaskar@gmail.com&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Reviewed-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
s/compier/compiler/

Link: https://lkml.kernel.org/r/20210224223325.29099-1-unixbhaskar@gmail.com
Signed-off-by: Bhaskar Chowdhury &lt;unixbhaskar@gmail.com&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Reviewed-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild</title>
<updated>2021-02-25T18:17:31+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-02-25T18:17:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6fbd6cf85a3be127454a1ad58525a3adcf8612ab'/>
<id>6fbd6cf85a3be127454a1ad58525a3adcf8612ab</id>
<content type='text'>
Pull Kbuild updates from Masahiro Yamada:

 - Fix false-positive build warnings for ARCH=ia64 builds

 - Optimize dictionary size for module compression with xz

 - Check the compiler and linker versions in Kconfig

 - Fix misuse of extra-y

 - Support DWARF v5 debug info

 - Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x
   exceeded the limit

 - Add generic syscall{tbl,hdr}.sh for cleanups across arches

 - Minor cleanups of genksyms

 - Minor cleanups of Kconfig

* tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits)
  initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD
  kbuild: remove deprecated 'always' and 'hostprogs-y/m'
  kbuild: parse C= and M= before changing the working directory
  kbuild: reuse this-makefile to define abs_srctree
  kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig
  kconfig: omit --oldaskconfig option for 'make config'
  kconfig: fix 'invalid option' for help option
  kconfig: remove dead code in conf_askvalue()
  kconfig: clean up nested if-conditionals in check_conf()
  kconfig: Remove duplicate call to sym_get_string_value()
  Makefile: Remove # characters from compiler string
  Makefile: reuse CC_VERSION_TEXT
  kbuild: check the minimum linker version in Kconfig
  kbuild: remove ld-version macro
  scripts: add generic syscallhdr.sh
  scripts: add generic syscalltbl.sh
  arch: syscalls: remove $(srctree)/ prefix from syscall tables
  arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work
  gen_compile_commands: prune some directories
  kbuild: simplify access to the kernel's version
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull Kbuild updates from Masahiro Yamada:

 - Fix false-positive build warnings for ARCH=ia64 builds

 - Optimize dictionary size for module compression with xz

 - Check the compiler and linker versions in Kconfig

 - Fix misuse of extra-y

 - Support DWARF v5 debug info

 - Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x
   exceeded the limit

 - Add generic syscall{tbl,hdr}.sh for cleanups across arches

 - Minor cleanups of genksyms

 - Minor cleanups of Kconfig

* tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits)
  initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD
  kbuild: remove deprecated 'always' and 'hostprogs-y/m'
  kbuild: parse C= and M= before changing the working directory
  kbuild: reuse this-makefile to define abs_srctree
  kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig
  kconfig: omit --oldaskconfig option for 'make config'
  kconfig: fix 'invalid option' for help option
  kconfig: remove dead code in conf_askvalue()
  kconfig: clean up nested if-conditionals in check_conf()
  kconfig: Remove duplicate call to sym_get_string_value()
  Makefile: Remove # characters from compiler string
  Makefile: reuse CC_VERSION_TEXT
  kbuild: check the minimum linker version in Kconfig
  kbuild: remove ld-version macro
  scripts: add generic syscallhdr.sh
  scripts: add generic syscalltbl.sh
  arch: syscalls: remove $(srctree)/ prefix from syscall tables
  arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work
  gen_compile_commands: prune some directories
  kbuild: simplify access to the kernel's version
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'akpm' (patches from Andrew)</title>
<updated>2021-02-25T00:20:38+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-02-25T00:20:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4c48faba5b7f18fb53e4aeeb768932f17c9da1ed'/>
<id>4c48faba5b7f18fb53e4aeeb768932f17c9da1ed</id>
<content type='text'>
Merge misc updates from Andrew Morton:
 "A few small subsystems and some of MM.

  172 patches.

  Subsystems affected by this patch series: hexagon, scripts, ntfs,
  ocfs2, vfs, and mm (slab-generic, slab, slub, debug, pagecache, swap,
  memcg, pagemap, mprotect, mremap, page-reporting, vmalloc, kasan,
  pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
  mempolicy, oom-kill, hugetlbfs, and migration)"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (172 commits)
  mm/migrate: remove unneeded semicolons
  hugetlbfs: remove unneeded return value of hugetlb_vmtruncate()
  hugetlbfs: fix some comment typos
  hugetlbfs: correct some obsolete comments about inode i_mutex
  hugetlbfs: make hugepage size conversion more readable
  hugetlbfs: remove meaningless variable avoid_reserve
  hugetlbfs: correct obsolete function name in hugetlbfs_read_iter()
  hugetlbfs: use helper macro default_hstate in init_hugetlbfs_fs
  hugetlbfs: remove useless BUG_ON(!inode) in hugetlbfs_setattr()
  hugetlbfs: remove special hugetlbfs_set_page_dirty()
  mm/hugetlb: change hugetlb_reserve_pages() to type bool
  mm, oom: fix a comment in dump_task()
  mm/mempolicy: use helper range_in_vma() in queue_pages_test_walk()
  numa balancing: migrate on fault among multiple bound nodes
  mm, compaction: make fast_isolate_freepages() stay within zone
  mm/compaction: fix misbehaviors of fast_find_migrateblock()
  mm/compaction: correct deferral logic for proactive compaction
  mm/compaction: remove duplicated VM_BUG_ON_PAGE !PageLocked
  mm/compaction: remove rcu_read_lock during page compaction
  z3fold: simplify the zhdr initialization code in init_z3fold_page()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge misc updates from Andrew Morton:
 "A few small subsystems and some of MM.

  172 patches.

  Subsystems affected by this patch series: hexagon, scripts, ntfs,
  ocfs2, vfs, and mm (slab-generic, slab, slub, debug, pagecache, swap,
  memcg, pagemap, mprotect, mremap, page-reporting, vmalloc, kasan,
  pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
  mempolicy, oom-kill, hugetlbfs, and migration)"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (172 commits)
  mm/migrate: remove unneeded semicolons
  hugetlbfs: remove unneeded return value of hugetlb_vmtruncate()
  hugetlbfs: fix some comment typos
  hugetlbfs: correct some obsolete comments about inode i_mutex
  hugetlbfs: make hugepage size conversion more readable
  hugetlbfs: remove meaningless variable avoid_reserve
  hugetlbfs: correct obsolete function name in hugetlbfs_read_iter()
  hugetlbfs: use helper macro default_hstate in init_hugetlbfs_fs
  hugetlbfs: remove useless BUG_ON(!inode) in hugetlbfs_setattr()
  hugetlbfs: remove special hugetlbfs_set_page_dirty()
  mm/hugetlb: change hugetlb_reserve_pages() to type bool
  mm, oom: fix a comment in dump_task()
  mm/mempolicy: use helper range_in_vma() in queue_pages_test_walk()
  numa balancing: migrate on fault among multiple bound nodes
  mm, compaction: make fast_isolate_freepages() stay within zone
  mm/compaction: fix misbehaviors of fast_find_migrateblock()
  mm/compaction: correct deferral logic for proactive compaction
  mm/compaction: remove duplicated VM_BUG_ON_PAGE !PageLocked
  mm/compaction: remove rcu_read_lock during page compaction
  z3fold: simplify the zhdr initialization code in init_z3fold_page()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>mm, slub: remove slub_memcg_sysfs boot param and CONFIG_SLUB_MEMCG_SYSFS_ON</title>
<updated>2021-02-24T21:38:27+00:00</updated>
<author>
<name>Vlastimil Babka</name>
<email>vbabka@suse.cz</email>
</author>
<published>2021-02-24T20:01:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fe2cce15d6821aea1766708a1cf031071cec815f'/>
<id>fe2cce15d6821aea1766708a1cf031071cec815f</id>
<content type='text'>
The boot param and config determine the value of memcg_sysfs_enabled,
which is unused since commit 10befea91b61 ("mm: memcg/slab: use a single
set of kmem_caches for all allocations") as there are no per-memcg kmem
caches anymore.

Link: https://lkml.kernel.org/r/20210127124745.7928-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Reviewed-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: Roman Gushchin &lt;guro@fb.com&gt;
Acked-by: David Rientjes &lt;rientjes@google.com&gt;
Reviewed-by: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: Pekka Enberg &lt;penberg@kernel.org&gt;
Cc: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The boot param and config determine the value of memcg_sysfs_enabled,
which is unused since commit 10befea91b61 ("mm: memcg/slab: use a single
set of kmem_caches for all allocations") as there are no per-memcg kmem
caches anymore.

Link: https://lkml.kernel.org/r/20210127124745.7928-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Reviewed-by: David Hildenbrand &lt;david@redhat.com&gt;
Acked-by: Roman Gushchin &lt;guro@fb.com&gt;
Acked-by: David Rientjes &lt;rientjes@google.com&gt;
Reviewed-by: Miaohe Lin &lt;linmiaohe@huawei.com&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: Pekka Enberg &lt;penberg@kernel.org&gt;
Cc: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Kbuild: enable TRIM_UNUSED_KSYMS again, with some guarding</title>
<updated>2021-02-24T16:57:06+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-02-24T16:57:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a555bdd0c58ce368fb1324f0e93d17f7c4babece'/>
<id>a555bdd0c58ce368fb1324f0e93d17f7c4babece</id>
<content type='text'>
In commit 5cf0fd591f2e ("Kbuild: disable TRIM_UNUSED_KSYMS option") I
disabled this option because it's hugely expensive at build time, and I
questioned how much use it gets.

Several people piped up and convinced me it's actually useful, so
instead of disabling it entirely, it now depends on EXPERT and gets
disabled by COMPILE_TEST builds so that 'allmodconfig' style things
don't enable it.

I still hope somebody will take a look at the build time issue, because
as Arnd also noted:

 "However, the combination of thinlto and trim indeed has a steep cost
  in compile time, taking almost twice as long as a normal defconfig
  (gc-sections makes it slightly faster)"

Cc: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Arnd Bergmann &lt;arnd@kernel.org&gt;
Cc: Jessica Yu &lt;jeyu@kernel.org&gt;
Cc: Cristoph Hellwig &lt;hch@lst.de&gt;,
Cc: Miroslav Benes &lt;mbenes@suse.cz&gt;
Cc: Emil Velikov &lt;emil.l.velikov@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In commit 5cf0fd591f2e ("Kbuild: disable TRIM_UNUSED_KSYMS option") I
disabled this option because it's hugely expensive at build time, and I
questioned how much use it gets.

Several people piped up and convinced me it's actually useful, so
instead of disabling it entirely, it now depends on EXPERT and gets
disabled by COMPILE_TEST builds so that 'allmodconfig' style things
don't enable it.

I still hope somebody will take a look at the build time issue, because
as Arnd also noted:

 "However, the combination of thinlto and trim indeed has a steep cost
  in compile time, taking almost twice as long as a normal defconfig
  (gc-sections makes it slightly faster)"

Cc: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Arnd Bergmann &lt;arnd@kernel.org&gt;
Cc: Jessica Yu &lt;jeyu@kernel.org&gt;
Cc: Cristoph Hellwig &lt;hch@lst.de&gt;,
Cc: Miroslav Benes &lt;mbenes@suse.cz&gt;
Cc: Emil Velikov &lt;emil.l.velikov@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Kbuild: disable TRIM_UNUSED_KSYMS option</title>
<updated>2021-02-23T20:21:58+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-02-23T20:21:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5cf0fd591f2e7833405bdc7ce2176c3502e8a11e'/>
<id>5cf0fd591f2e7833405bdc7ce2176c3502e8a11e</id>
<content type='text'>
The removal of EXPORT_UNUSED_SYMBOL() in commit 367948220fce looks like
(and was sold as) a no-op, but it actually had a rather serious and
subtle side effect: the UNUSED_SYMBOLS option not only enabled the
removed (unused) functionality, it also _disabled_ the TRIM_UNUSED_KSYMS
functionality.

And it turns out that TRIM_UNUSED_KSYMS is a huge time waste, and takes
up a third of the kernel build time for me.  For no actual upside, since
no distro is likely to ever be able to enable it (because they all
support external kernel modules).

Rather than re-enable EXPORT_UNUSED_SYMBOL, this just disables the
TRIM_UNUSED_KSYMS option by marking it broken.  I'm tempted to just
remove the support entirely, but maybe somebody has a use-case and can
fix the behavior of it.

I could have just disabled it for COMPILE_TEST, but it really smells
like the TRIM_UNUSED_KSYMS option is badly done and not really useful,
so this takes the more direct approach - let's see if anybody ever
actually notices or complains.

Cc: Miroslav Benes &lt;mbenes@suse.cz&gt;
Cc: Emil Velikov &lt;emil.l.velikov@gmail.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Jessica Yu &lt;jeyu@kernel.org&gt;
Fixes: 367948220fce ("module: remove EXPORT_UNUSED_SYMBOL*")
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The removal of EXPORT_UNUSED_SYMBOL() in commit 367948220fce looks like
(and was sold as) a no-op, but it actually had a rather serious and
subtle side effect: the UNUSED_SYMBOLS option not only enabled the
removed (unused) functionality, it also _disabled_ the TRIM_UNUSED_KSYMS
functionality.

And it turns out that TRIM_UNUSED_KSYMS is a huge time waste, and takes
up a third of the kernel build time for me.  For no actual upside, since
no distro is likely to ever be able to enable it (because they all
support external kernel modules).

Rather than re-enable EXPORT_UNUSED_SYMBOL, this just disables the
TRIM_UNUSED_KSYMS option by marking it broken.  I'm tempted to just
remove the support entirely, but maybe somebody has a use-case and can
fix the behavior of it.

I could have just disabled it for COMPILE_TEST, but it really smells
like the TRIM_UNUSED_KSYMS option is badly done and not really useful,
so this takes the more direct approach - let's see if anybody ever
actually notices or complains.

Cc: Miroslav Benes &lt;mbenes@suse.cz&gt;
Cc: Emil Velikov &lt;emil.l.velikov@gmail.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Jessica Yu &lt;jeyu@kernel.org&gt;
Fixes: 367948220fce ("module: remove EXPORT_UNUSED_SYMBOL*")
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
