bpf: Fix bpf_prog_pack when PMU_SIZE is not defined

PMD_SIZE is not available in some special config, e.g. ARCH=arm with
CONFIG_MMU=n. Use bpf_prog_pack of PAGE_SIZE in these cases.

Fixes: 1ca2b2ac2c72 ("bpf: Select proper size for bpf_prog_pack")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220321180009.1944482-3-song@kernel.org

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index f6b20fcbeb24ff3aa5b237ba9d5a83f46c973642..13e9dbeeedf36efe6fe5bb268ee2f7ebe6c44f2f 100644 (file)
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -840,12 +840,23 @@ static int bpf_prog_chunk_count(void)
 static DEFINE_MUTEX(pack_mutex);
 static LIST_HEAD(pack_list);
 
+/* PMD_SIZE is not available in some special config, e.g. ARCH=arm with
+ * CONFIG_MMU=n. Use PAGE_SIZE in these cases.
+ */
+#ifdef PMD_SIZE
+#define BPF_HPAGE_SIZE PMD_SIZE
+#define BPF_HPAGE_MASK PMD_MASK
+#else
+#define BPF_HPAGE_SIZE PAGE_SIZE
+#define BPF_HPAGE_MASK PAGE_MASK
+#endif
+
 static size_t select_bpf_prog_pack_size(void)
 {
        size_t size;
        void *ptr;
 
-       size = PMD_SIZE * num_online_nodes();
+       size = BPF_HPAGE_SIZE * num_online_nodes();
        ptr = module_alloc(size);
 
        /* Test whether we can get huge pages. If not just use PAGE_SIZE
@@ -855,7 +866,7 @@ static size_t select_bpf_prog_pack_size(void)
                size = PAGE_SIZE;
                bpf_prog_pack_mask = PAGE_MASK;
        } else {
-               bpf_prog_pack_mask = PMD_MASK;
+               bpf_prog_pack_mask = BPF_HPAGE_MASK;
        }
 
        vfree(ptr);