The patch titled
Subject: mm: Kconfig: reorganize misplaced mm options
has been added to the -mm mm-unstable branch. Its filename is
mm-kconfig-reorganize-misplaced-mm-options.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-kconfig-reorganize-misplaced-mm-options.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Vlastimil Babka <vbabka@xxxxxxx>
Subject: mm: Kconfig: reorganize misplaced mm options
Date: Wed, 25 May 2022 13:25:59 +0200
After commits 7b42f1041c98 ("mm: Kconfig: move swap and slab config
options to the MM section") and 519bcb797907 ("mm: Kconfig: group swap,
slab, hotplug and thp options into submenus") we now have nicely organized
mm related config options. I have noticed some that were still misplaced,
so this moves them from various places into the new structure:
VM_EVENT_COUNTERS, COMPAT_BRK, MMAP_ALLOW_UNINITIALIZED to mm/Kconfig and
general MM section.
SLUB_STATS to mm/Kconfig and the slab submenu.
DEBUG_SLAB, SLUB_DEBUG, SLUB_DEBUG_ON to mm/Kconfig.debug and the Kernel
hacking / Memory Debugging submenu.
Link: https://lkml.kernel.org/r/20220525112559.1139-1-vbabka@xxxxxxx
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
init/Kconfig | 53 -----------------------------------------
lib/Kconfig.debug | 34 --------------------------
mm/Kconfig | 56 ++++++++++++++++++++++++++++++++++++++++++++
mm/Kconfig.debug | 31 ++++++++++++++++++++++++
4 files changed, 87 insertions(+), 87 deletions(-)
--- a/init/Kconfig~mm-kconfig-reorganize-misplaced-mm-options
+++ a/init/Kconfig
@@ -1828,59 +1828,6 @@ config DEBUG_PERF_USE_VMALLOC
endmenu
-config VM_EVENT_COUNTERS
- default y
- bool "Enable VM event counters for /proc/vmstat" if EXPERT
- help
- VM event counters are needed for event counts to be shown.
- This option allows the disabling of the VM event counters
- on EXPERT systems. /proc/vmstat will only show page counts
- if VM event counters are disabled.
-
-config SLUB_DEBUG
- default y
- bool "Enable SLUB debugging support" if EXPERT
- depends on SLUB && SYSFS
- help
- SLUB has extensive debug support features. Disabling these can
- result in significant savings in code size. This also disables
- SLUB sysfs support. /sys/slab will not exist and there will be
- no support for cache validation etc.
-
-config COMPAT_BRK
- bool "Disable heap randomization"
- default y
- help
- Randomizing heap placement makes heap exploits harder, but it
- also breaks ancient binaries (including anything libc5 based).
- This option changes the bootup default to heap randomization
- disabled, and can be overridden at runtime by setting
- /proc/sys/kernel/randomize_va_space to 2.
-
- On non-ancient distros (post-2000 ones) N is usually a safe choice.
-
-config MMAP_ALLOW_UNINITIALIZED
- bool "Allow mmapped anonymous memory to be uninitialized"
- depends on EXPERT && !MMU
- default n
- help
- Normally, and according to the Linux spec, anonymous memory obtained
- from mmap() has its contents cleared before it is passed to
- userspace. Enabling this config option allows you to request that
- mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
- providing a huge performance boost. If this option is not enabled,
- then the flag will be ignored.
-
- This is taken advantage of by uClibc's malloc(), and also by
- ELF-FDPIC binfmt's brk and stack allocator.
-
- Because of the obvious security issues, this option should only be
- enabled on embedded devices where you control what is run in
- userspace. Since that isn't generally a problem on no-MMU systems,
- it is normally safe to say Y here.
-
- See Documentation/admin-guide/mm/nommu-mmap.rst for more information.
-
config SYSTEM_DATA_VERIFICATION
def_bool n
select SYSTEM_TRUSTED_KEYRING
--- a/lib/Kconfig.debug~mm-kconfig-reorganize-misplaced-mm-options
+++ a/lib/Kconfig.debug
@@ -698,40 +698,6 @@ config DEBUG_OBJECTS_ENABLE_DEFAULT
help
Debug objects boot parameter default value
-config DEBUG_SLAB
- bool "Debug slab memory allocations"
- depends on DEBUG_KERNEL && SLAB
- help
- Say Y here to have the kernel do limited verification on memory
- allocation as well as poisoning memory on free to catch use of freed
- memory. This can make kmalloc/kfree-intensive workloads much slower.
-
-config SLUB_DEBUG_ON
- bool "SLUB debugging on by default"
- depends on SLUB && SLUB_DEBUG
- default n
- help
- Boot with debugging on by default. SLUB boots by default with
- the runtime debug capabilities switched off. Enabling this is
- equivalent to specifying the "slub_debug" parameter on boot.
- There is no support for more fine grained debug control like
- possible with slub_debug=xxx. SLUB debugging may be switched
- off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying
- "slub_debug=-".
-
-config SLUB_STATS
- default n
- bool "Enable SLUB performance statistics"
- depends on SLUB && SYSFS
- help
- SLUB statistics are useful to debug SLUBs allocation behavior in
- order find ways to optimize the allocator. This should never be
- enabled for production use since keeping statistics slows down
- the allocator by a few percentage points. The slabinfo command
- supports the determination of the most active slabs to figure
- out which slabs are relevant to a particular load.
- Try running: slabinfo -DA
-
config HAVE_DEBUG_KMEMLEAK
bool
--- a/mm/Kconfig~mm-kconfig-reorganize-misplaced-mm-options
+++ a/mm/Kconfig
@@ -270,6 +270,19 @@ config SLAB_FREELIST_HARDENED
sanity-checking than others. This option is most effective with
CONFIG_SLUB.
+config SLUB_STATS
+ default n
+ bool "Enable SLUB performance statistics"
+ depends on SLUB && SYSFS
+ help
+ SLUB statistics are useful to debug SLUBs allocation behavior in
+ order find ways to optimize the allocator. This should never be
+ enabled for production use since keeping statistics slows down
+ the allocator by a few percentage points. The slabinfo command
+ supports the determination of the most active slabs to figure
+ out which slabs are relevant to a particular load.
+ Try running: slabinfo -DA
+
config SLUB_CPU_PARTIAL
default y
depends on SLUB && SMP
@@ -307,6 +320,40 @@ config SHUFFLE_PAGE_ALLOCATOR
Say Y if unsure.
+config COMPAT_BRK
+ bool "Disable heap randomization"
+ default y
+ help
+ Randomizing heap placement makes heap exploits harder, but it
+ also breaks ancient binaries (including anything libc5 based).
+ This option changes the bootup default to heap randomization
+ disabled, and can be overridden at runtime by setting
+ /proc/sys/kernel/randomize_va_space to 2.
+
+ On non-ancient distros (post-2000 ones) N is usually a safe choice.
+
+config MMAP_ALLOW_UNINITIALIZED
+ bool "Allow mmapped anonymous memory to be uninitialized"
+ depends on EXPERT && !MMU
+ default n
+ help
+ Normally, and according to the Linux spec, anonymous memory obtained
+ from mmap() has its contents cleared before it is passed to
+ userspace. Enabling this config option allows you to request that
+ mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
+ providing a huge performance boost. If this option is not enabled,
+ then the flag will be ignored.
+
+ This is taken advantage of by uClibc's malloc(), and also by
+ ELF-FDPIC binfmt's brk and stack allocator.
+
+ Because of the obvious security issues, this option should only be
+ enabled on embedded devices where you control what is run in
+ userspace. Since that isn't generally a problem on no-MMU systems,
+ it is normally safe to say Y here.
+
+ See Documentation/admin-guide/mm/nommu-mmap.rst for more information.
+
config SELECT_MEMORY_MODEL
def_bool y
depends on ARCH_SELECT_MEMORY_MODEL
@@ -964,6 +1011,15 @@ config ARCH_USES_HIGH_VMA_FLAGS
config ARCH_HAS_PKEYS
bool
+config VM_EVENT_COUNTERS
+ default y
+ bool "Enable VM event counters for /proc/vmstat" if EXPERT
+ help
+ VM event counters are needed for event counts to be shown.
+ This option allows the disabling of the VM event counters
+ on EXPERT systems. /proc/vmstat will only show page counts
+ if VM event counters are disabled.
+
config PERCPU_STATS
bool "Collect percpu memory statistics"
help
--- a/mm/Kconfig.debug~mm-kconfig-reorganize-misplaced-mm-options
+++ a/mm/Kconfig.debug
@@ -45,6 +45,37 @@ config DEBUG_PAGEALLOC_ENABLE_DEFAULT
Enable debug page memory allocations by default? This value
can be overridden by debug_pagealloc=off|on.
+config DEBUG_SLAB
+ bool "Debug slab memory allocations"
+ depends on DEBUG_KERNEL && SLAB
+ help
+ Say Y here to have the kernel do limited verification on memory
+ allocation as well as poisoning memory on free to catch use of freed
+ memory. This can make kmalloc/kfree-intensive workloads much slower.
+
+config SLUB_DEBUG
+ default y
+ bool "Enable SLUB debugging support" if EXPERT
+ depends on SLUB && SYSFS
+ help
+ SLUB has extensive debug support features. Disabling these can
+ result in significant savings in code size. This also disables
+ SLUB sysfs support. /sys/slab will not exist and there will be
+ no support for cache validation etc.
+
+config SLUB_DEBUG_ON
+ bool "SLUB debugging on by default"
+ depends on SLUB && SLUB_DEBUG
+ default n
+ help
+ Boot with debugging on by default. SLUB boots by default with
+ the runtime debug capabilities switched off. Enabling this is
+ equivalent to specifying the "slub_debug" parameter on boot.
+ There is no support for more fine grained debug control like
+ possible with slub_debug=xxx. SLUB debugging may be switched
+ off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying
+ "slub_debug=-".
+
config PAGE_OWNER
bool "Track page owner"
depends on DEBUG_KERNEL && STACKTRACE_SUPPORT
_
Patches currently in -mm which might be from vbabka@xxxxxxx are
mm-kconfig-reorganize-misplaced-mm-options.patch
