WARNING: line length of 88 exceeds 80 columns
#66: FILE: include/linux/bpf_verifier.h:891:
+	/* Per-callsite copy of parent's converged at_stack_in for cross-frame fills. */

WARNING: line length of 83 exceeds 80 columns
#170: FILE: kernel/bpf/liveness.c:842:
+		s16 off[MAX_ARG_OFFSETS]; /* byte offsets; off_cnt says how many */

WARNING: line length of 86 exceeds 80 columns
#202: FILE: kernel/bpf/liveness.c:874:
+static void clear_overlapping_stack_slots(struct arg_track *at_stack, s16 off, u32 sz)

WARNING: line length of 81 exceeds 80 columns
#220: FILE: kernel/bpf/liveness.c:892:
+static void verbose_arg_track(struct bpf_verifier_env *env, struct arg_track *at)

ERROR: trailing statements should be on next line
#225: FILE: kernel/bpf/liveness.c:897:
+	case ARG_NONE:      verbose(env, "_");                          break;

ERROR: trailing statements should be on next line
#226: FILE: kernel/bpf/liveness.c:898:
+	case ARG_UNVISITED: verbose(env, "?");                          break;

ERROR: trailing statements should be on next line
#227: FILE: kernel/bpf/liveness.c:899:
+	case ARG_IMPRECISE: verbose(env, "IMP%x", at->mask);            break;

WARNING: line length of 81 exceeds 80 columns
#276: FILE: kernel/bpf/liveness.c:948:
+static struct arg_track arg_merge_offsets(struct arg_track a, struct arg_track b)

CHECK: Please use a blank line after function/struct/union/enum declarations
#311: FILE: kernel/bpf/liveness.c:983:
+}
+/*

WARNING: line length of 82 exceeds 80 columns
#317: FILE: kernel/bpf/liveness.c:989:
+static struct arg_track arg_join_imprecise(struct arg_track a, struct arg_track b)

WARNING: line length of 84 exceeds 80 columns
#376: FILE: kernel/bpf/liveness.c:1048:
+static bool arg_track_join(struct bpf_verifier_env *env, int idx, int target, int r,

WARNING: line length of 86 exceeds 80 columns
#414: FILE: kernel/bpf/liveness.c:1086:
+	if (dst->frame >= 0 && (src->frame == ARG_NONE || src->frame == dst->frame)) {

WARNING: line length of 83 exceeds 80 columns
#540: FILE: kernel/bpf/liveness.c:1212:
+			clear_overlapping_stack_slots(at_stack_out, insn->off, sz);

WARNING: line length of 87 exceeds 80 columns
#584: FILE: kernel/bpf/liveness.c:1256:
+static void arg_track_log(struct bpf_verifier_env *env, struct bpf_insn *insn, int idx,

WARNING: line length of 81 exceeds 80 columns
#585: FILE: kernel/bpf/liveness.c:1257:
+			  struct arg_track *at_in, struct arg_track *at_stack_in,

WARNING: line length of 83 exceeds 80 columns
#586: FILE: kernel/bpf/liveness.c:1258:
+			  struct arg_track *at_out, struct arg_track *at_stack_out)

WARNING: line length of 97 exceeds 80 columns
#614: FILE: kernel/bpf/liveness.c:1286:
+		verbose(env, "\tfp%+d: ", -(i + 1) * 8); verbose_arg_track(env, &at_stack_in[i]);

WARNING: line length of 84 exceeds 80 columns
#628: FILE: kernel/bpf/liveness.c:1300:
+			   struct arg_track *at_out, struct arg_track *at_stack_out,

WARNING: line length of 92 exceeds 80 columns
#649: FILE: kernel/bpf/liveness.c:1321:
+				/* Any other 64-bit alu on the pointer makes it imprecise */

WARNING: line length of 85 exceeds 80 columns
#671: FILE: kernel/bpf/liveness.c:1343:
+		 * at_stack_out[slot] is not cleared by the helper and subprog calls.

WARNING: line length of 104 exceeds 80 columns
#672: FILE: kernel/bpf/liveness.c:1344:
+		 * The fill_from_stack() may return the stale spill — which is an FP-derived arg_track

WARNING: line length of 98 exceeds 80 columns
#673: FILE: kernel/bpf/liveness.c:1345:
+		 * (the value that was originally spilled there). The loaded register then carries

WARNING: line length of 104 exceeds 80 columns
#674: FILE: kernel/bpf/liveness.c:1346:
+		 * a phantom FP-derived identity that doesn't correspond to what's actually in the slot.

WARNING: line length of 98 exceeds 80 columns
#675: FILE: kernel/bpf/liveness.c:1347:
+		 * This phantom FP pointer propagates forward, and wherever it's subsequently used

WARNING: line length of 92 exceeds 80 columns
#676: FILE: kernel/bpf/liveness.c:1348:
+		 * (as a helper argument, another store, etc.), it sets stack liveness bits.

WARNING: line length of 86 exceeds 80 columns
#677: FILE: kernel/bpf/liveness.c:1349:
+		 * Those bits correspond to stack accesses that don't actually happen.

WARNING: line length of 103 exceeds 80 columns
#678: FILE: kernel/bpf/liveness.c:1350:
+		 * So the effect is over-reporting stack liveness — marking slots as live that aren't

WARNING: line length of 100 exceeds 80 columns
#679: FILE: kernel/bpf/liveness.c:1351:
+		 * actually accessed. The verifier preserves more state than necessary across calls,

WARNING: line length of 98 exceeds 80 columns
#682: FILE: kernel/bpf/liveness.c:1354:
+		 * helpers can scratch stack slots, but they won't make a valid pointer out of it.

WARNING: line length of 89 exceeds 80 columns
#683: FILE: kernel/bpf/liveness.c:1355:
+		 * subprogs are allowed to write into parent slots, but they cannot write

WARNING: line length of 86 exceeds 80 columns
#684: FILE: kernel/bpf/liveness.c:1356:
+		 * _any_ FP-derived pointer into it (either their own or parent's FP).

WARNING: line length of 92 exceeds 80 columns
#690: FILE: kernel/bpf/liveness.c:1362:
+		bool src_is_local_fp = insn->src_reg == BPF_REG_FP || src->frame == depth ||

WARNING: line length of 97 exceeds 80 columns
#691: FILE: kernel/bpf/liveness.c:1363:
+				       (src->frame == ARG_IMPRECISE && (src->mask & BIT(depth)));

WARNING: line length of 84 exceeds 80 columns
#699: FILE: kernel/bpf/liveness.c:1371:
+		if (src_is_local_fp && BPF_MODE(insn->code) == BPF_MEM && sz == 8) {

WARNING: line length of 97 exceeds 80 columns
#700: FILE: kernel/bpf/liveness.c:1372:
+			*dst = fill_from_stack(insn, at_out, insn->src_reg, at_stack_out, depth);

WARNING: line length of 85 exceeds 80 columns
#726: FILE: kernel/bpf/liveness.c:1398:
+		dst_is_local_fp = insn->dst_reg == BPF_REG_FP || dst->frame == depth;

WARNING: line length of 85 exceeds 80 columns
#733: FILE: kernel/bpf/liveness.c:1405:
+				clear_stack_for_all_offs(insn, at_out, insn->dst_reg,

WARNING: line length of 90 exceeds 80 columns
#745: FILE: kernel/bpf/liveness.c:1417:
+		bool dst_is_local_fp = insn->dst_reg == BPF_REG_FP || dst->frame == depth;

WARNING: line length of 86 exceeds 80 columns
#777: FILE: kernel/bpf/liveness.c:1449:
+		/* helper/kfunc read unknown amount of bytes from fp_off until fp+0 */

WARNING: line length of 82 exceeds 80 columns
#786: FILE: kernel/bpf/liveness.c:1458:
+		slot_lo = max_t(s32, (-fp_off - access_bytes) / STACK_SLOT_SZ, 0);

WARNING: line length of 102 exceeds 80 columns
#794: FILE: kernel/bpf/liveness.c:1466:
+		slot_lo = max_t(s32, (-fp_off - access_bytes + STACK_SLOT_SZ - 1) / STACK_SLOT_SZ, 0);

WARNING: line length of 84 exceeds 80 columns
#819: FILE: kernel/bpf/liveness.c:1491:
+			return mark_stack_read(instance, frame, insn_idx, SPIS_ALL);

WARNING: line length of 105 exceeds 80 columns
#827: FILE: kernel/bpf/liveness.c:1499:
+		err = record_stack_access_off(env, instance, arg->off[i], access_bytes, frame, insn_idx);

WARNING: line length of 83 exceeds 80 columns
#838: FILE: kernel/bpf/liveness.c:1510:
+static int record_imprecise(struct func_instance *instance, u32 mask, u32 insn_idx)

WARNING: line length of 89 exceeds 80 columns
#907: FILE: kernel/bpf/liveness.c:1579:
+		return record_stack_access(env, instance, ptr, sz, ptr->frame, insn_idx);

WARNING: line length of 90 exceeds 80 columns
#939: FILE: kernel/bpf/liveness.c:1611:
+			bytes = bpf_helper_stack_access_bytes(env, insn, r - 1, insn_idx);

WARNING: line length of 89 exceeds 80 columns
#941: FILE: kernel/bpf/liveness.c:1613:
+			bytes = bpf_kfunc_stack_access_bytes(env, insn, r - 1, insn_idx);

WARNING: line length of 87 exceeds 80 columns
#944: FILE: kernel/bpf/liveness.c:1616:
+				err = mark_stack_read(instance, f, insn_idx, SPIS_ALL);

WARNING: line length of 97 exceeds 80 columns
#954: FILE: kernel/bpf/liveness.c:1626:
+			err = record_stack_access(env, instance, &at[r], bytes, frame, insn_idx);

WARNING: line length of 90 exceeds 80 columns
#1023: FILE: kernel/bpf/liveness.c:1695:
+				     struct arg_track (*at_stack_in)[MAX_ARG_SPILL_SLOTS])

WARNING: line length of 106 exceeds 80 columns
#1037: FILE: kernel/bpf/liveness.c:1709:
+						    env->prog->aux->func_info[subprog].type_id)->name_off)

WARNING: line length of 93 exceeds 80 columns
#1136: FILE: kernel/bpf/liveness.c:1808:
+	at_stack_out = kvmalloc_objs(*at_stack_out, MAX_ARG_SPILL_SLOTS, GFP_KERNEL_ACCOUNT);

WARNING: line length of 86 exceeds 80 columns
#1164: FILE: kernel/bpf/liveness.c:1836:
+		verbose(env, "subprog#%d: analyzing (depth %d)...\n", subprog, depth);

WARNING: line length of 83 exceeds 80 columns
#1175: FILE: kernel/bpf/liveness.c:1847:
+		if (!arg_is_visited(&at_in[i][0]) && !arg_is_visited(&at_in[i][1]))

WARNING: line length of 98 exceeds 80 columns
#1179: FILE: kernel/bpf/liveness.c:1851:
+		memcpy(at_stack_out, at_stack_in[i], MAX_ARG_SPILL_SLOTS * sizeof(*at_stack_out));

WARNING: line length of 90 exceeds 80 columns
#1181: FILE: kernel/bpf/liveness.c:1853:
+		arg_track_xfer(env, insn, idx, at_out, at_stack_out, instance, callsites);

WARNING: line length of 94 exceeds 80 columns
#1182: FILE: kernel/bpf/liveness.c:1854:
+		arg_track_log(env, insn, idx, at_in[i], at_stack_in[i], at_out, at_stack_out);

WARNING: line length of 84 exceeds 80 columns
#1197: FILE: kernel/bpf/liveness.c:1869:
+							  &at_in[ti][r], at_out[r]);

WARNING: line length of 83 exceeds 80 columns
#1200: FILE: kernel/bpf/liveness.c:1872:
+				changed |= arg_track_join(env, idx, target, -r - 1,

WARNING: line length of 96 exceeds 80 columns
#1201: FILE: kernel/bpf/liveness.c:1873:
+							  &at_stack_in[ti][r], at_stack_out[r]);

WARNING: line length of 87 exceeds 80 columns
#1228: FILE: kernel/bpf/liveness.c:1900:
+					      MAX_ARG_SPILL_SLOTS, GFP_KERNEL_ACCOUNT);

WARNING: line length of 95 exceeds 80 columns
#1232: FILE: kernel/bpf/liveness.c:1904:
+			       at_stack_in[i], sizeof(struct arg_track) * MAX_ARG_SPILL_SLOTS);

WARNING: line length of 89 exceeds 80 columns
#1279: FILE: kernel/bpf/liveness.c:1951:
+	err = compute_subprog_args(env, &info[subprog], entry_args, instance, callsites);

WARNING: line length of 100 exceeds 80 columns
#1305: FILE: kernel/bpf/liveness.c:1977:
+			callee = find_callback_subprog(env, insn, idx, &caller_reg, &cb_callee_reg);

WARNING: line length of 91 exceeds 80 columns
#1308: FILE: kernel/bpf/liveness.c:1980:
+				 * same bpf_loop() calls two different callbacks and passes

WARNING: line length of 89 exceeds 80 columns
#1311: FILE: kernel/bpf/liveness.c:1983:
+				if (info[subprog].at_in[j][caller_reg].frame == ARG_NONE)

WARNING: line length of 90 exceeds 80 columns
#1314: FILE: kernel/bpf/liveness.c:1986:
+					err = mark_stack_read(instance, f, idx, SPIS_ALL);

WARNING: line length of 88 exceeds 80 columns
#1325: FILE: kernel/bpf/liveness.c:1997:
+			callee_args[cb_callee_reg] = info[subprog].at_in[j][caller_reg];

WARNING: line length of 90 exceeds 80 columns
#1337: FILE: kernel/bpf/liveness.c:2009:
+		err = analyze_subprog(env, callee_args, info, callee_instance, callsites);

WARNING: line length of 81 exceeds 80 columns
#1357: FILE: kernel/bpf/liveness.c:2029:
+	env->callsite_at_stack = kvzalloc_objs(*env->callsite_at_stack, insn_cnt,

total: 3 errors, 66 warnings, 1 checks, 1379 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit 72e97689ea44 ("bpf: introduce forward arg-tracking dataflow analysis") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT BAD_REPORTED_BY_LINK CAMELCASE COMMIT_LOG_LONG_LINE FILE_PATH_CHANGES GIT_COMMIT_ID MACRO_ARG_REUSE NO_AUTHOR_SIGN_OFF

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.