Daniel Borkmann d407bd25a2 bpf: don't trigger OOM killer under pressure with map alloc ... This patch adds two helpers, bpf_map_area_alloc() and bpf_map_area_free(), that are to be used for map allocations. Using kmalloc() for very large allocations can cause excessive work within the page allocator, so i) fall back earlier to vmalloc() when the attempt is considered costly anyway, and even more importantly ii) don't trigger OOM killer with any of the allocators. Since this is based on a user space request, for example, when creating maps with element pre-allocation, we really want such requests to fail instead of killing other user space processes. Also, don't spam the kernel log with warnings should any of the allocations fail under pressure. Given that, we can make backend selection in bpf_map_area_alloc() generic, and convert all maps over to use this API for spots with potentially large allocation requests. Note, replacing the one kmalloc_array() is fine as overflow checks happen earlier in htab_map_alloc(), since it must also protect the multiplication for vmalloc() should kmalloc_array() fail. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>		2017-01-18 17:12:26 -05:00
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arraymap.c	bpf: don't trigger OOM killer under pressure with map alloc	2017-01-18 17:12:26 -05:00
bpf_lru_list.c	bpf: Fix compilation warning in __bpf_lru_list_rotate_inactive	2016-11-16 11:30:56 -05:00
bpf_lru_list.h	bpf: Add percpu LRU list	2016-11-15 11:50:20 -05:00
cgroup.c	bpf: Add new cgroup attach type to enable sock modifications	2016-12-02 13:46:08 -05:00
core.c	bpf: rework prog_digest into prog_tag	2017-01-16 14:03:31 -05:00
hashtab.c	bpf: don't trigger OOM killer under pressure with map alloc	2017-01-18 17:12:26 -05:00
helpers.c	bpf: add helper for retrieving current numa node id	2016-10-22 17:05:52 -04:00
inode.c	bpf: allow for mount options to specify permissions	2016-11-27 20:38:47 -05:00
Makefile	cgroup: add support for eBPF programs	2016-11-25 16:25:52 -05:00
percpu_freelist.c	bpf: introduce percpu_freelist	2016-03-08 15:28:31 -05:00
percpu_freelist.h	bpf: introduce percpu_freelist	2016-03-08 15:28:31 -05:00
stackmap.c	bpf: don't trigger OOM killer under pressure with map alloc	2017-01-18 17:12:26 -05:00
syscall.c	bpf: don't trigger OOM killer under pressure with map alloc	2017-01-18 17:12:26 -05:00
verifier.c	bpf: rework prog_digest into prog_tag	2017-01-16 14:03:31 -05:00