WARNING: line length of 91 exceeds 80 columns
#85: FILE: include/linux/bpf_verifier.h:1083:
+int bpf_mark_stack_read(struct bpf_verifier_env *env, u32 frameno, u32 insn_idx, u64 mask);

WARNING: line length of 91 exceeds 80 columns
#89: FILE: include/linux/bpf_verifier.h:1087:
+int bpf_live_stack_query_init(struct bpf_verifier_env *env, struct bpf_verifier_state *st);

WARNING: added, moved or deleted file(s), does MAINTAINERS need updating?
#108: 
new file mode 100644

WARNING: line length of 85 exceeds 80 columns
#143: FILE: kernel/bpf/liveness.c:31:
+ *     (any slot in "must_write" set is guaranteed to be written by the instruction).

WARNING: line length of 89 exceeds 80 columns
#149: FILE: kernel/bpf/liveness.c:37:
+ *     state[cc, i].live_after = U [state[cc, s].live_before for s in insn_successors(i)]

WARNING: line length of 81 exceeds 80 columns
#176: FILE: kernel/bpf/liveness.c:64:
+ *   - "must_write_acc" set is intersected with the call site's "must_write" set;

WARNING: line length of 89 exceeds 80 columns
#200: FILE: kernel/bpf/liveness.c:88:
+	 * - sp_starts[curframe] used to get insn relative index within current function;

WARNING: line length of 85 exceeds 80 columns
#204: FILE: kernel/bpf/liveness.c:92:
+	u32 curframe;			/* depth of callsites and sp_starts arrays */

WARNING: line length of 86 exceeds 80 columns
#208: FILE: kernel/bpf/liveness.c:96:
+	u64 may_read;		/* stack slots that may be read by this instruction */

WARNING: line length of 96 exceeds 80 columns
#210: FILE: kernel/bpf/liveness.c:98:
+	u64 must_write_acc;	/* stack slots written by this instruction and its successors */

WARNING: line length of 98 exceeds 80 columns
#211: FILE: kernel/bpf/liveness.c:99:
+	u64 live_before;	/* stack slots that may be read by this insn and its successors */

WARNING: line length of 94 exceeds 80 columns
#227: FILE: kernel/bpf/liveness.c:115:
+	/* For each instruction a flag telling if "must_write" had been initialized for it. */

WARNING: line length of 92 exceeds 80 columns
#232: FILE: kernel/bpf/liveness.c:120:
+	struct func_instance *instances[MAX_CALL_FRAMES]; /* valid in range [0..curframe] */

WARNING: line length of 93 exceeds 80 columns
#238: FILE: kernel/bpf/liveness.c:126:
+	DECLARE_HASHTABLE(func_instances, 8);		/* maps callchain to func_instance */

WARNING: line length of 98 exceeds 80 columns
#239: FILE: kernel/bpf/liveness.c:127:
+	struct live_stack_query live_stack_query;	/* cache to avoid repetitive ht lookups */

WARNING: line length of 95 exceeds 80 columns
#240: FILE: kernel/bpf/liveness.c:128:
+	/* Cached instance corresponding to env->cur_state, avoids per-instruction ht lookup */

WARNING: line length of 83 exceeds 80 columns
#243: FILE: kernel/bpf/liveness.c:131:
+	 * Below fields are used to accumulate stack write marks for instruction at

WARNING: line length of 90 exceeds 80 columns
#251: FILE: kernel/bpf/liveness.c:139:
+static void compute_callchain(struct bpf_verifier_env *env, struct bpf_verifier_state *st,

WARNING: line length of 86 exceeds 80 columns
#259: FILE: kernel/bpf/liveness.c:147:
+		callchain->sp_starts[i] = subprog_info[st->frame[i]->subprogno].start;

WARNING: line length of 94 exceeds 80 columns
#264: FILE: kernel/bpf/liveness.c:152:
+	callchain->callsites[callchain->curframe] = callchain->sp_starts[callchain->curframe];

WARNING: line length of 94 exceeds 80 columns
#302: FILE: kernel/bpf/liveness.c:190:
+	subprog = bpf_find_containing_subprog(env, callchain->sp_starts[callchain->curframe]);

WARNING: line length of 86 exceeds 80 columns
#308: FILE: kernel/bpf/liveness.c:196:
+	result->must_write_set = kvcalloc(subprog_sz, sizeof(*result->must_write_set),

WARNING: line length of 88 exceeds 80 columns
#345: FILE: kernel/bpf/liveness.c:233:
+	hash_for_each_safe(env->liveness->func_instances, bkt, tmp, instance, hl_node) {

WARNING: line length of 86 exceeds 80 columns
#360: FILE: kernel/bpf/liveness.c:248:
+	return insn_idx - instance->callchain.sp_starts[instance->callchain.curframe];

WARNING: line length of 85 exceeds 80 columns
#379: FILE: kernel/bpf/liveness.c:267:
+		arr = kvcalloc(instance->insn_cnt, sizeof(*arr), GFP_KERNEL_ACCOUNT);

WARNING: line length of 99 exceeds 80 columns
#392: FILE: kernel/bpf/liveness.c:280:
+/* If @env->liveness->cur_instance is null, set it to instance corresponding to @env->cur_state. */

WARNING: line length of 82 exceeds 80 columns
#401: FILE: kernel/bpf/liveness.c:289:
+	instance = lookup_instance(env, env->cur_state, env->cur_state->curframe);

WARNING: line length of 93 exceeds 80 columns
#411: FILE: kernel/bpf/liveness.c:299:
+			   struct func_instance *instance, u32 frame, u32 insn_idx, u64 mask)

WARNING: line length of 88 exceeds 80 columns
#427: FILE: kernel/bpf/liveness.c:315:
+int bpf_mark_stack_read(struct bpf_verifier_env *env, u32 frame, u32 insn_idx, u64 mask)

WARNING: line length of 94 exceeds 80 columns
#432: FILE: kernel/bpf/liveness.c:320:
+	err = err ?: mark_stack_read(env, env->liveness->cur_instance, frame, insn_idx, mask);

WARNING: line length of 81 exceeds 80 columns
#437: FILE: kernel/bpf/liveness.c:325:
+				    struct func_instance *instance, u32 insn_idx)

WARNING: line length of 90 exceeds 80 columns
#487: FILE: kernel/bpf/liveness.c:375:
+		masks = alloc_frame_masks(env, instance, frame, liveness->write_insn_idx);

WARNING: line length of 98 exceeds 80 columns
#492: FILE: kernel/bpf/liveness.c:380:
+		 * If instruction at this callchain is seen for a first time, set must_write equal

WARNING: line length of 81 exceeds 80 columns
#493: FILE: kernel/bpf/liveness.c:381:
+		 * to @mask. Otherwise take intersection with the previous value.

WARNING: line length of 85 exceeds 80 columns
#509: FILE: kernel/bpf/liveness.c:397:
+static char *fmt_callchain(struct bpf_verifier_env *env, struct callchain *callchain)

WARNING: line length of 99 exceeds 80 columns
#517: FILE: kernel/bpf/liveness.c:405:
+		buf += snprintf(buf, buf_end - buf, "%s%d", i ? "," : "", callchain->callsites[i]);

WARNING: line length of 86 exceeds 80 columns
#522: FILE: kernel/bpf/liveness.c:410:
+static void log_mask_change(struct bpf_verifier_env *env, struct callchain *callchain,

WARNING: line length of 81 exceeds 80 columns
#523: FILE: kernel/bpf/liveness.c:411:
+			    char *pfx, u32 frame, u32 insn_idx, u64 old, u64 new)

WARNING: line length of 99 exceeds 80 columns
#531: FILE: kernel/bpf/liveness.c:419:
+	bpf_log(&env->log, "%s frame %d insn %d ", fmt_callchain(env, callchain), frame, insn_idx);

WARNING: line length of 89 exceeds 80 columns
#533: FILE: kernel/bpf/liveness.c:421:
+		bpf_fmt_stack_mask(env->tmp_str_buf, sizeof(env->tmp_str_buf), new_ones);

WARNING: line length of 90 exceeds 80 columns
#537: FILE: kernel/bpf/liveness.c:425:
+		bpf_fmt_stack_mask(env->tmp_str_buf, sizeof(env->tmp_str_buf), new_zeros);

WARNING: line length of 90 exceeds 80 columns
#552: FILE: kernel/bpf/liveness.c:440:
+	callchain.callsites[callchain.curframe] = callchain.sp_starts[callchain.curframe];

WARNING: line length of 88 exceeds 80 columns
#562: FILE: kernel/bpf/liveness.c:450:
+ * Transfer @may_read and @must_write_acc marks from the first instruction of @instance,

WARNING: line length of 95 exceeds 80 columns
#584: FILE: kernel/bpf/liveness.c:472:
+		err = mark_stack_read(env, outer_instance, frame, callsite, insn->live_before);

WARNING: line length of 87 exceeds 80 columns
#593: FILE: kernel/bpf/liveness.c:481:
+			       struct func_instance *instance, u32 frame, u32 insn_idx)

WARNING: line length of 87 exceeds 80 columns
#634: FILE: kernel/bpf/liveness.c:522:
+				frame, insn_idx, insn->must_write_acc, must_write_acc);

WARNING: line length of 88 exceeds 80 columns
#642: FILE: kernel/bpf/liveness.c:530:
+static int update_instance(struct bpf_verifier_env *env, struct func_instance *instance)

WARNING: line length of 96 exceeds 80 columns
#663: FILE: kernel/bpf/liveness.c:551:
+				insn = get_frame_masks(instance, frame, this_subprog_start + i);

WARNING: line length of 81 exceeds 80 columns
#677: FILE: kernel/bpf/liveness.c:565:
+		for (frame = 0; frame <= instance->callchain.curframe; frame++) {

WARNING: line length of 96 exceeds 80 columns
#682: FILE: kernel/bpf/liveness.c:570:
+				changed |= update_insn(env, instance, frame, insn_postorder[i]);

WARNING: line length of 82 exceeds 80 columns
#687: FILE: kernel/bpf/liveness.c:575:
+		bpf_log(&env->log, "%s live stack update done in %d iterations\n",

WARNING: line length of 89 exceeds 80 columns
#690: FILE: kernel/bpf/liveness.c:578:
+	/* transfer marks accumulated for outer frames to outer func instance (caller) */

WARNING: line length of 94 exceeds 80 columns
#730: FILE: kernel/bpf/liveness.c:618:
+static bool is_live_before(struct func_instance *instance, u32 insn_idx, u32 frameno, u32 spi)

WARNING: line length of 90 exceeds 80 columns
#738: FILE: kernel/bpf/liveness.c:626:
+int bpf_live_stack_query_init(struct bpf_verifier_env *env, struct bpf_verifier_state *st)

WARNING: line length of 87 exceeds 80 columns
#759: FILE: kernel/bpf/liveness.c:647:
+	 * Slot is alive if it is read before q->st->insn_idx in current func instance,

total: 0 errors, 55 warnings, 0 checks, 710 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 ccec41331ccd ("bpf: callchain sensitive stack liveness tracking using CFG") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT BAD_REPORTED_BY_LINK CAMELCASE COMMIT_LOG_LONG_LINE 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.
total: 0 errors, 55 warnings, 0 checks, 710 lines checked