linux/mm
Daniel Borkmann 0ea7eeec24 mm, percpu: add support for __GFP_NOWARN flag
Add an option for pcpu_alloc() to support __GFP_NOWARN flag.
Currently, we always throw a warning when size or alignment
is unsupported (and also dump stack on failed allocation
requests). The warning itself is harmless since we return
NULL anyway for any failed request, which callers are
required to handle anyway. However, it becomes harmful when
panic_on_warn is set.

The rationale for the WARN() in pcpu_alloc() is that it can
be tracked when larger than supported allocation requests are
made such that allocations limits can be tweaked if warranted.
This makes sense for in-kernel users, however, there are users
of pcpu allocator where allocation size is derived from user
space requests, e.g. when creating BPF maps. In these cases,
the requests should fail gracefully without throwing a splat.

The current work-around was to check allocation size against
the upper limit of PCPU_MIN_UNIT_SIZE from call-sites for
bailing out prior to a call to pcpu_alloc() in order to
avoid throwing the WARN(). This is bad in multiple ways since
PCPU_MIN_UNIT_SIZE is an implementation detail, and having
the checks on call-sites only complicates the code for no
good reason. Thus, lets fix it generically by supporting the
__GFP_NOWARN flag that users can then use with calling the
__alloc_percpu_gfp() helper instead.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-19 13:13:49 +01:00
..
kasan Merge branch 'linus' into locking/core, to pick up fixes 2017-08-10 12:20:53 +02:00
backing-dev.c mm/backing-dev.c: fix an error handling path in 'cgwb_create()' 2017-09-11 14:16:44 -06:00
balloon_compaction.c mm/migrate: new migrate mode MIGRATE_SYNC_NO_COPY 2017-09-08 18:26:46 -07:00
bootmem.c mm/bootmem.c: cosmetic improvement of code readability 2017-02-22 16:41:29 -08:00
cleancache.c fs: switch ->s_uuid to uuid_t 2017-06-05 16:59:12 +02:00
cma_debug.c mm/cma_debug.c: fix stack corruption due to sprintf usage 2017-08-18 15:32:02 -07:00
cma.c cma: fix calculation of aligned offset 2017-07-10 16:32:32 -07:00
cma.h cma: Store a name in the cma structure 2017-04-18 20:41:12 +02:00
compaction.c mm,compaction: serialize waitqueue_active() checks (for real) 2017-10-03 17:54:24 -07:00
debug_page_ref.c
debug.c mm: make tlb_flush_pending global 2017-08-10 15:54:07 -07:00
dmapool.c lib/vsprintf.c: remove %Z support 2017-02-27 18:43:47 -08:00
early_ioremap.c x86/mm: Add support to access boot related data in the clear 2017-07-18 11:38:02 +02:00
fadvise.c mm: fadvise: avoid fadvise for fs without backing device 2017-09-08 18:26:47 -07:00
failslab.c
filemap.c mm: have filemap_check_and_advance_wb_err clear AS_EIO/AS_ENOSPC 2017-10-03 17:54:24 -07:00
frame_vector.c treewide: use kv[mz]alloc* rather than opencoded variants 2017-05-08 17:15:13 -07:00
frontswap.c
gup.c mm/device-public-memory: device memory cache coherent with CPU 2017-09-08 18:26:46 -07:00
highmem.c
hmm.c mm/hmm: avoid bloating arch that do not make use of HMM 2017-09-08 18:26:46 -07:00
huge_memory.c mm: soft-dirty: keep soft-dirty bits over thp migration 2017-09-08 18:26:45 -07:00
hugetlb_cgroup.c
hugetlb.c powerpc updates for 4.14 2017-09-07 10:15:40 -07:00
hwpoison-inject.c mm: hwpoison: call shake_page() unconditionally 2017-05-03 15:52:12 -07:00
init-mm.c
internal.h mm, oom: do not rely on TIF_MEMDIE for memory reserves access 2017-09-06 17:27:30 -07:00
interval_tree.c lib/interval_tree: fast overlap detection 2017-09-08 18:26:49 -07:00
Kconfig mm/hmm: avoid bloating arch that do not make use of HMM 2017-09-08 18:26:46 -07:00
Kconfig.debug mm: enable page poisoning early at boot 2017-05-03 15:52:10 -07:00
khugepaged.c mm: make PR_SET_THP_DISABLE immediately active 2017-07-10 16:32:31 -07:00
kmemcheck.c mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU 2017-04-18 11:42:36 -07:00
kmemleak-test.c
kmemleak.c mm: kmemleak: treat vm_struct as alternative reference to vmalloc'ed objects 2017-07-06 16:24:34 -07:00
ksm.c ksm: fix unlocked iteration over vmas in cmp_and_merge_page() 2017-10-03 17:54:23 -07:00
list_lru.c mm: memcontrol: use vmalloc fallback for large kmem memcg arrays 2017-10-03 17:54:25 -07:00
maccess.c
madvise.c mm, hugetlb, soft_offline: save compound page order before page migration 2017-10-03 17:54:24 -07:00
Makefile mm/hmm: avoid bloating arch that do not make use of HMM 2017-09-08 18:26:46 -07:00
memblock.c mm/memblock.c: reversed logic in memblock_discard() 2017-08-25 16:12:46 -07:00
memcontrol.c net: memcontrol: defer call to mem_cgroup_sk_alloc() 2017-10-09 20:55:01 -07:00
memory_hotplug.c mm/memory_hotplug: define find_{smallest|biggest}_section_pfn as unsigned long 2017-10-03 17:54:26 -07:00
memory-failure.c x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages 2017-08-17 10:30:49 +02:00
memory.c mm/device-public-memory: fix edge case in _vm_normal_page() 2017-10-03 17:54:25 -07:00
mempolicy.c mm/mempolicy.c: remove BUG_ON() checks for VMA inside mpol_misplaced() 2017-09-08 18:26:47 -07:00
mempool.c sched/wait: Rename wait_queue_t => wait_queue_entry_t 2017-06-20 12:18:27 +02:00
memtest.c
migrate.c mm/hmm: avoid bloating arch that do not make use of HMM 2017-09-08 18:26:46 -07:00
mincore.c mm: remove shmem_mapping() shmem_zero_setup() duplicates 2017-02-24 17:46:56 -08:00
mlock.c mm/mlock.c: use page_zone() instead of page_zone_id() 2017-09-08 18:26:47 -07:00
mm_init.c
mmap.c lib/interval_tree: fast overlap detection 2017-09-08 18:26:49 -07:00
mmu_context.c sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h> 2017-03-02 08:42:38 +01:00
mmu_notifier.c mm/mmu_notifier: kill invalidate_page 2017-08-31 16:13:00 -07:00
mmzone.c mm/mmzone.c: swap likely to unlikely as code logic is different for next_zones_zonelist() 2017-02-22 16:41:29 -08:00
mprotect.c mm/ZONE_DEVICE: new type of ZONE_DEVICE for unaddressable memory 2017-09-08 18:26:46 -07:00
mremap.c mm: thp: check pmd migration entry in common path 2017-09-08 18:26:45 -07:00
msync.c
nobootmem.c mm: discard memblock data later 2017-08-18 15:32:01 -07:00
nommu.c Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:13:32 -07:00
oom_kill.c mm, oom_reaper: skip mm structs with mmu notifiers 2017-10-03 17:54:24 -07:00
page_alloc.c mm, page_alloc: add scheduling point to memmap_init_zone 2017-10-03 17:54:25 -07:00
page_counter.c
page_ext.c mm, page_ext: periodically reschedule during page_ext_init() 2017-09-06 17:27:26 -07:00
page_idle.c mm/page_idle.c: constify attribute_group structures 2017-09-06 17:27:27 -07:00
page_io.c Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block 2017-09-07 11:59:42 -07:00
page_isolation.c mm: unify new_node_page and alloc_migrate_target 2017-07-10 16:32:31 -07:00
page_owner.c mm, page_owner: skip unnecessary stack_trace entries 2017-09-13 18:53:16 -07:00
page_poison.c mm: enable page poisoning early at boot 2017-05-03 15:52:10 -07:00
page_vma_mapped.c mm/migrate: support un-addressable ZONE_DEVICE page in migration 2017-09-08 18:26:46 -07:00
page-writeback.c mm: rename global_page_state to global_zone_page_state 2017-09-06 17:27:29 -07:00
pagewalk.c mm/hugetlb: add size parameter to huge_pte_offset() 2017-07-06 16:24:34 -07:00
percpu-internal.h percpu: skip chunks if the alloc does not fit in the contig hint 2017-07-26 17:41:05 -04:00
percpu-km.c percpu: replace area map allocator with bitmap 2017-07-26 17:41:05 -04:00
percpu-stats.c percpu: fix starting offset for chunk statistics traversal 2017-09-27 14:45:57 -07:00
percpu-vm.c percpu: fix static checker warnings in pcpu_destroy_chunk 2017-06-29 11:23:38 -04:00
percpu.c mm, percpu: add support for __GFP_NOWARN flag 2017-10-19 13:13:49 +01:00
pgtable-generic.c mm: thp: enable thp migration in generic path 2017-09-08 18:26:45 -07:00
process_vm_access.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/mm.h> 2017-03-02 08:42:28 +01:00
quicklist.c
readahead.c
rmap.c lib/interval_tree: fast overlap detection 2017-09-08 18:26:49 -07:00
rodata_test.c mm: fix RODATA_TEST failure "rodata_test: test data was not read only" 2017-10-03 17:54:24 -07:00
shmem.c mm: treewide: remove GFP_TEMPORARY allocation flag 2017-09-13 18:53:16 -07:00
slab_common.c mm: memcontrol: use vmalloc fallback for large kmem memcg arrays 2017-10-03 17:54:25 -07:00
slab.c mm: memcontrol: account slab stats per lruvec 2017-07-06 16:24:35 -07:00
slab.h locking/lockdep: Rework FS_RECLAIM annotation 2017-08-10 12:29:03 +02:00
slob.c locking/lockdep: Rework FS_RECLAIM annotation 2017-08-10 12:29:03 +02:00
slub.c mm: treewide: remove GFP_TEMPORARY allocation flag 2017-09-13 18:53:16 -07:00
sparse-vmemmap.c mm, sparse, page_ext: drop ugly N_HIGH_MEMORY branches for allocations 2017-09-06 17:27:26 -07:00
sparse.c mm/sparse.c: fix typo in online_mem_sections 2017-09-08 18:26:47 -07:00
swap_cgroup.c mm, THP, swap: delay splitting THP during swap out 2017-07-06 16:24:31 -07:00
swap_slots.c mm/swap_slots.c: don't disable preemption while taking the per-CPU cache 2017-07-10 16:32:32 -07:00
swap_state.c mm: fix data corruption caused by lazyfree page 2017-10-03 17:54:25 -07:00
swap.c mm: avoid marking swap cached page as lazyfree 2017-10-03 17:54:24 -07:00
swapfile.c mm/swapfile.c: fix swapon frontswap_map memory leak on error 2017-09-08 18:26:47 -07:00
truncate.c mm/truncate.c: fix THP handling in invalidate_mapping_pages() 2017-07-10 16:32:32 -07:00
usercopy.c mm/usercopy: Drop extra is_vmalloc_or_module() check 2017-04-05 12:30:18 -07:00
userfaultfd.c userfaultfd: shmem: wire up shmem_mfill_zeropage_pte 2017-09-06 17:27:28 -07:00
util.c mm: rename global_page_state to global_zone_page_state 2017-09-06 17:27:29 -07:00
vmacache.c sched/headers: Prepare to move 'init_task' and 'init_thread_union' from <linux/sched.h> to <linux/sched/task.h> 2017-03-02 08:42:38 +01:00
vmalloc.c mm/vmalloc.c: don't reinvent the wheel but use existing llist API 2017-09-06 17:27:29 -07:00
vmpressure.c mm, vmpressure: pass-through notification support 2017-07-10 16:32:31 -07:00
vmscan.c mm, THP, swap: add THP swapping out fallback counting 2017-09-06 17:27:28 -07:00
vmstat.c mm: consider the number in local CPUs when reading NUMA stats 2017-09-08 18:26:47 -07:00
workingset.c mm: memcontrol: per-lruvec stats infrastructure 2017-07-06 16:24:35 -07:00
z3fold.c z3fold: fix stale list handling 2017-10-03 17:54:24 -07:00
zbud.c
zpool.c
zsmalloc.c mm/zsmalloc.c: change stat type parameter to int 2017-09-08 18:26:47 -07:00
zswap.c mm/zswap.c: delete an error message for a failed memory allocation in zswap_dstmem_prepare() 2017-07-06 16:24:35 -07:00