linux/include
Sebastian Andrzej Siewior 8f3ce3d996 mm: percpu: increase PERCPU_DYNAMIC_SIZE_SHIFT on certain builds.
Arnd reported a build failure due to the BUILD_BUG_ON() statement in
alloc_kmem_cache_cpus().  The test

  PERCPU_DYNAMIC_EARLY_SIZE < NR_KMALLOC_TYPES * KMALLOC_SHIFT_HIGH * sizeof(struct kmem_cache_cpu)

The factors that increase the right side of the equation:
- PAGE_SIZE > 4KiB increases KMALLOC_SHIFT_HIGH
- For the local_lock_t in kmem_cache_cpu:
  - PREEMPT_RT adds an actual lock.
  - LOCKDEP increases the size of the lock.
  - LOCK_STAT adds additional bytes plus padding to the lockdep
    structure.

The net difference with and without PREEMPT_RT is 88 bytes for the
lock_lock_t, 96 bytes for kmem_cache_cpu due to additional padding.  This
is enough to exceed the 80KiB limit with 16KiB page size - the 8KiB page
size is fine.

Increase PERCPU_DYNAMIC_SIZE_SHIFT to 13 on configs with PAGE_SIZE larger
than 4KiB and LOCKDEP enabled.

Link: https://lkml.kernel.org/r/20241007143049.gyMpEu89@linutronix.de
Fixes: d8fccd9ca5 ("arm64: Allow to enable PREEMPT_RT.")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202410020326.iaZIteIx-lkp@intel.com/
Reported-by: Arnd Bergmann <arnd@kernel.org>
Closes: https://lore.kernel.org/20241004095702.637528-1-arnd@kernel.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-10-17 00:28:07 -07:00
..
acpi Power management updates for 6.12-rc1 2024-09-16 07:47:50 +02:00
asm-generic move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
clocksource
crypto move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
cxl cxl: Move mailbox related bits to the same context 2024-09-12 08:38:01 -07:00
drm Short summary of fixes pull: 2024-10-01 08:15:55 +10:00
dt-bindings soc: convert ep93xx to devicetree 2024-09-26 12:00:25 -07:00
keys KEYS: Remove unused declarations 2024-09-20 18:28:26 +03:00
kunit The core clk framework is left largely untouched this time around except for 2024-09-23 15:01:48 -07:00
kvm
linux mm: percpu: increase PERCPU_DYNAMIC_SIZE_SHIFT on certain builds. 2024-10-17 00:28:07 -07:00
math-emu
media media: cec: move cec_get/put_device to header 2024-09-05 20:12:15 +02:00
memory
misc
net mctp: Handle error of rtnl_register_module(). 2024-10-10 15:39:35 +02:00
pcmcia
ras
rdma move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
rv
scsi move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
soc soc: driver updates for 6.12 2024-09-17 10:48:09 +02:00
sound ALSA: hda: fix trigger_tstamp_latched 2024-10-02 12:50:24 +02:00
target move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
trace for-6.12-rc1-tag 2024-10-04 10:05:13 -07:00
uapi Including fixes from ieee802154, bluetooth and netfilter. 2024-10-03 09:44:00 -07:00
ufs Many singleton patches - please see the various changelogs for details. 2024-09-21 08:20:50 -07:00
vdso random: vDSO: add a __vdso_getrandom prototype for all architectures 2024-09-13 17:28:35 +02:00
video
xen xen: sync elfnote.h from xen tree 2024-09-25 14:15:04 +02:00