mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-01-01 10:43:43 +00:00
8f3ce3d996
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:
|
||
---|---|---|
.. | ||
acpi | ||
asm-generic | ||
clocksource | ||
crypto | ||
cxl | ||
drm | ||
dt-bindings | ||
keys | ||
kunit | ||
kvm | ||
linux | ||
math-emu | ||
media | ||
memory | ||
misc | ||
net | ||
pcmcia | ||
ras | ||
rdma | ||
rv | ||
scsi | ||
soc | ||
sound | ||
target | ||
trace | ||
uapi | ||
ufs | ||
vdso | ||
video | ||
xen |