Hi Brendan, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on bpf-next/master] [also build test WARNING on bpf/master powerpc/next linus/master v5.10-rc5 next-20201123] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Brendan-Jackman/Atomics-for-eBPF/20201124-013549 base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: m68k-randconfig-r005-20201123 (attached as .config) compiler: m68k-linux-gcc (GCC) 9.3.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/0day-ci/linux/commit/b2b5923320904ef8c33183e8e88042588eb99397 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Brendan-Jackman/Atomics-for-eBPF/20201124-013549 git checkout b2b5923320904ef8c33183e8e88042588eb99397 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=m68k If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): In file included from include/linux/kernel.h:11, from include/linux/list.h:9, from include/linux/preempt.h:11, from arch/m68k/include/asm/irqflags.h:6, from include/linux/irqflags.h:16, from arch/m68k/include/asm/atomic.h:6, from include/linux/atomic.h:7, from include/linux/filter.h:10, from kernel/bpf/core.c:21: include/linux/scatterlist.h: In function 'sg_set_buf': arch/m68k/include/asm/page_no.h:33:50: warning: ordered comparison of pointer with null pointer [-Wextra] 33 | #define virt_addr_valid(kaddr) (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \ | ^~ include/linux/compiler.h:78:42: note: in definition of macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ include/linux/scatterlist.h:143:2: note: in expansion of macro 'BUG_ON' 143 | BUG_ON(!virt_addr_valid(buf)); | ^~~~~~ include/linux/scatterlist.h:143:10: note: in expansion of macro 'virt_addr_valid' 143 | BUG_ON(!virt_addr_valid(buf)); | ^~~~~~~~~~~~~~~ kernel/bpf/core.c: At top level: kernel/bpf/core.c:1358:12: warning: no previous prototype for 'bpf_probe_read_kernel' [-Wmissing-prototypes] 1358 | u64 __weak bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr) | ^~~~~~~~~~~~~~~~~~~~~ In file included from kernel/bpf/core.c:21: kernel/bpf/core.c: In function '___bpf_prog_run': include/linux/filter.h:899:3: warning: cast between incompatible function types from 'u64 (*)(u64, u64, u64, u64, u64)' {aka 'long long unsigned int (*)(long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int)'} to 'u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)' {aka 'long long unsigned int (*)(long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, const struct bpf_insn *)'} [-Wcast-function-type] 899 | ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \ | ^ kernel/bpf/core.c:1526:13: note: in expansion of macro '__bpf_call_base_args' 1526 | BPF_R0 = (__bpf_call_base_args + insn->imm)(BPF_R1, BPF_R2, | ^~~~~~~~~~~~~~~~~~~~ >> kernel/bpf/core.c:1656:5: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 1656 | (atomic64_t *)(s64) (DST + insn->off)); | ^ In file included from kernel/bpf/core.c:21: kernel/bpf/core.c: In function 'bpf_patch_call_args': include/linux/filter.h:899:3: warning: cast between incompatible function types from 'u64 (*)(u64, u64, u64, u64, u64)' {aka 'long long unsigned int (*)(long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int)'} to 'u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)' {aka 'long long unsigned int (*)(long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, const struct bpf_insn *)'} [-Wcast-function-type] 899 | ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \ | ^ kernel/bpf/core.c:1743:3: note: in expansion of macro '__bpf_call_base_args' 1743 | __bpf_call_base_args; | ^~~~~~~~~~~~~~~~~~~~ vim +1656 kernel/bpf/core.c 1628 1629 STX_ATOMIC_W: 1630 switch (IMM) { 1631 case BPF_ADD: 1632 /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */ 1633 atomic_add((u32) SRC, (atomic_t *)(unsigned long) 1634 (DST + insn->off)); 1635 break; 1636 case BPF_ADD | BPF_FETCH: 1637 SRC = (u32) atomic_fetch_add( 1638 (u32) SRC, 1639 (atomic_t *)(unsigned long) (DST + insn->off)); 1640 break; 1641 default: 1642 goto default_label; 1643 } 1644 CONT; 1645 1646 STX_ATOMIC_DW: 1647 switch (IMM) { 1648 case BPF_ADD: 1649 /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */ 1650 atomic64_add((u64) SRC, (atomic64_t *)(unsigned long) 1651 (DST + insn->off)); 1652 break; 1653 case BPF_ADD | BPF_FETCH: 1654 SRC = (u64) atomic64_fetch_add( 1655 (u64) SRC, > 1656 (atomic64_t *)(s64) (DST + insn->off)); 1657 break; 1658 default: 1659 goto default_label; 1660 } 1661 CONT; 1662 1663 default_label: 1664 /* If we ever reach this, we have a bug somewhere. Die hard here 1665 * instead of just returning 0; we could be somewhere in a subprog, 1666 * so execution could continue otherwise which we do /not/ want. 1667 * 1668 * Note, verifier whitelists all opcodes in bpf_opcode_in_insntable(). 1669 */ 1670 pr_warn("BPF interpreter: unknown opcode %02x (imm: 0x%x)\n", 1671 insn->code, insn->imm); 1672 BUG_ON(1); 1673 return 0; 1674 } 1675 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org