summaryrefslogtreecommitdiff
path: root/kernel/bpf/hashtab.c
diff options
context:
space:
mode:
authorArnd Bergmann <arnd@arndb.de>2020-11-26 22:06:49 +0100
committerArnd Bergmann <arnd@arndb.de>2020-11-26 22:06:50 +0100
commitdbae2736fd9f131111d3e826396b45c36d1de211 (patch)
tree43abb2d7768dc58d8fcd5a18bedecc72de901702 /kernel/bpf/hashtab.c
parent4765df4d3a132764077a83ed0df4ee4cc7866fbb (diff)
parentacfdd18591eaac25446e976a0c0d190f8b3dbfb1 (diff)
Merge tag 'zynqmp-soc-fixes-for-v5.10-rc6' of https://github.com/Xilinx/linux-xlnx into arm/fixes
arm64: soc: ZynqMP SoC fixes for v5.10-rc6 - Fix SD dll reset issue by using proper macro - Fix PM feature checking for Xilinx Versal SoC * tag 'zynqmp-soc-fixes-for-v5.10-rc6' of https://github.com/Xilinx/linux-xlnx: (337 commits) firmware: xilinx: Use hash-table for api feature check firmware: xilinx: Fix SD DLL node reset issue Linux 5.10-rc4 kvm: mmu: fix is_tdp_mmu_check when the TDP MMU is not in use afs: Fix afs_write_end() when called with copied == 0 [ver #3] ocfs2: initialize ip_next_orphan panic: don't dump stack twice on warn hugetlbfs: fix anon huge page migration race mm: memcontrol: fix missing wakeup polling thread kernel/watchdog: fix watchdog_allowed_mask not used warning reboot: fix overflow parsing reboot cpu number Revert "kernel/reboot.c: convert simple_strtoul to kstrtoint" compiler.h: fix barrier_data() on clang mm/gup: use unpin_user_pages() in __gup_longterm_locked() mm/slub: fix panic in slab_alloc_node() mailmap: fix entry for Dmitry Baryshkov/Eremin-Solenikov mm/vmscan: fix NR_ISOLATED_FILE corruption on 64-bit mm/compaction: stop isolation if too many pages are isolated and we have pages to migrate mm/compaction: count pages and stop correctly during page isolation drm/nouveau/kms/nv50-: Use atomic encoder callbacks everywhere ... Link: https://lore.kernel.org/r/fd5ab967-f3cf-95fb-7947-5477ff85f97e@monstr.eu Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'kernel/bpf/hashtab.c')
-rw-r--r--kernel/bpf/hashtab.c30
1 files changed, 28 insertions, 2 deletions
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 1815e97d4c9c..1fccba6e88c4 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -821,6 +821,32 @@ static void pcpu_copy_value(struct bpf_htab *htab, void __percpu *pptr,
}
}
+static void pcpu_init_value(struct bpf_htab *htab, void __percpu *pptr,
+ void *value, bool onallcpus)
+{
+ /* When using prealloc and not setting the initial value on all cpus,
+ * zero-fill element values for other cpus (just as what happens when
+ * not using prealloc). Otherwise, bpf program has no way to ensure
+ * known initial values for cpus other than current one
+ * (onallcpus=false always when coming from bpf prog).
+ */
+ if (htab_is_prealloc(htab) && !onallcpus) {
+ u32 size = round_up(htab->map.value_size, 8);
+ int current_cpu = raw_smp_processor_id();
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ if (cpu == current_cpu)
+ bpf_long_memcpy(per_cpu_ptr(pptr, cpu), value,
+ size);
+ else
+ memset(per_cpu_ptr(pptr, cpu), 0, size);
+ }
+ } else {
+ pcpu_copy_value(htab, pptr, value, onallcpus);
+ }
+}
+
static bool fd_htab_map_needs_adjust(const struct bpf_htab *htab)
{
return htab->map.map_type == BPF_MAP_TYPE_HASH_OF_MAPS &&
@@ -891,7 +917,7 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
}
}
- pcpu_copy_value(htab, pptr, value, onallcpus);
+ pcpu_init_value(htab, pptr, value, onallcpus);
if (!prealloc)
htab_elem_set_ptr(l_new, key_size, pptr);
@@ -1183,7 +1209,7 @@ static int __htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
pcpu_copy_value(htab, htab_elem_get_ptr(l_old, key_size),
value, onallcpus);
} else {
- pcpu_copy_value(htab, htab_elem_get_ptr(l_new, key_size),
+ pcpu_init_value(htab, htab_elem_get_ptr(l_new, key_size),
value, onallcpus);
hlist_nulls_add_head_rcu(&l_new->hash_node, head);
l_new = NULL;