Commit d6170e4a authored Mar 11, 2024 by Puranjay Mohan Committed by Alexei Starovoitov Mar 11, 2024

bpf: hardcode BPF_PROG_PACK_SIZE to 2MB * num_possible_nodes()



On some architectures like ARM64, PMD_SIZE can be really large in some
configurations. Like with CONFIG_ARM64_64K_PAGES=y the PMD_SIZE is
512MB.

Use 2MB * num_possible_nodes() as the size for allocations done through
the prog pack allocator. On most architectures, PMD_SIZE will be equal
to 2MB in case of 4KB pages and will be greater than 2MB for bigger page
sizes.

Fixes: ea2babac ("bpf: Simplify bpf_prog_pack_[size|mask]")
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Closes: https://lore.kernel.org/all/7e216c88-77ee-47b8-becc-a0f780868d3c@sirena.org.uk/


Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202403092219.dhgcuz2G-lkp@intel.com/


Suggested-by: Song Liu <song@kernel.org>
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Message-ID: <20240311122722.86232-1-puranjay12@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

parent 379b97bb

kernel/bpf/core.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -893,7 +893,12 @@ static LIST_HEAD(pack_list);
		* CONFIG_MMU=n. Use PAGE_SIZE in these cases.
		*/
		#ifdef PMD_SIZE
		#define BPF_PROG_PACK_SIZE (PMD_SIZE * num_possible_nodes())
		/* PMD_SIZE is really big for some archs. It doesn't make sense to
		* reserve too much memory in one allocation. Hardcode BPF_PROG_PACK_SIZE to
		* 2MiB * num_possible_nodes(). On most architectures PMD_SIZE will be
		* greater than or equal to 2MB.
		*/
		#define BPF_PROG_PACK_SIZE (SZ_2M * num_possible_nodes())
		#else
		#define BPF_PROG_PACK_SIZE PAGE_SIZE
		#endif