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Moe Charm (CI) b6d9c92f71 Fix: SuperSlab guess loop & header magic SEGV (random_mixed/mid_large_mt) 
## Problem
bench_random_mixed_hakmem and bench_mid_large_mt_hakmem crashed with SEGV:
- random_mixed: Exit 139 (SEGV) ❌
- mid_large_mt: Exit 139 (SEGV) ❌
- Larson: 838K ops/s ✅ (worked fine)

Error: Unmapped memory dereference in free path

## Root Causes (2 bugs found by Ultrathink Task)

### Bug 1: Guess Loop (core/box/hak_free_api.inc.h:92-95)
```c
for (int lg=21; lg>=20; lg--) {
    SuperSlab* guess=(SuperSlab*)((uintptr_t)ptr & ~mask);
    if (guess && guess->magic==SUPERSLAB_MAGIC) {  // ← SEGV
        // Dereferences unmapped memory
    }
}
```

### Bug 2: Header Magic Check (core/box/hak_free_api.inc.h:115)
```c
void* raw = (char*)ptr - HEADER_SIZE;
AllocHeader* hdr = (AllocHeader*)raw;
if (hdr->magic != HAKMEM_MAGIC) {  // ← SEGV
    // Dereferences unmapped memory if ptr has no header
}
```

**Why SEGV:**
- Registry lookup fails (allocation not from SuperSlab)
- Guess loop calculates 1MB/2MB aligned address
- No memory mapping validation
- Dereferences unmapped memory → SEGV

**Why Larson worked but random_mixed failed:**
- Larson: All from SuperSlab → registry hit → never reaches guess loop
- random_mixed: Diverse sizes (8-4096B) → registry miss → enters buggy paths

**Why LD_PRELOAD worked:**
- hak_core_init.inc.h:119-121 disables SuperSlab by default
- → SS-first path skipped → buggy code never executed

## Fix (2-part)

### Part 1: Remove Guess Loop
File: core/box/hak_free_api.inc.h:92-95
- Deleted unsafe guess loop (4 lines)
- If registry lookup fails, allocation is not from SuperSlab

### Part 2: Add Memory Safety Check
File: core/hakmem_internal.h:277-294
```c
static inline int hak_is_memory_readable(void* addr) {
    unsigned char vec;
    return mincore(addr, 1, &vec) == 0;  // Check if mapped
}
```

File: core/box/hak_free_api.inc.h:115-131
```c
if (!hak_is_memory_readable(raw)) {
    // Not accessible → route to appropriate handler
    // Prevents SEGV on unmapped memory
    goto done;
}
// Safe to dereference now
AllocHeader* hdr = (AllocHeader*)raw;
```

## Verification

| Test | Before | After | Result |
|------|--------|-------|--------|
| random_mixed (2KB) | ❌ SEGV | ✅ 2.22M ops/s | 🎉 Fixed |
| random_mixed (4KB) | ❌ SEGV | ✅ 2.58M ops/s | 🎉 Fixed |
| Larson 4T | ✅ 838K | ✅ 838K ops/s | ✅ No regression |

**Performance Impact:** 0% (mincore only on fallback path)

## Investigation

- Complete analysis: SEGV_ROOT_CAUSE_COMPLETE.md
- Fix report: SEGV_FIX_REPORT.md
- Previous investigation: SEGFAULT_INVESTIGATION_REPORT.md

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>
2025-11-07 17:34:24 +09:00
..
box
Fix: SuperSlab guess loop & header magic SEGV (random_mixed/mid_large_mt)
2025-11-07 17:34:24 +09:00
hakmem_ace_controller.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace_controller.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace_metrics.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace_metrics.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace_stats.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace_stats.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace_ucb1.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace_ucb1.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ace.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_batch.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_batch.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_bigcache.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_bigcache.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_build_flags.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_config.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_config.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_debug.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_debug.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_elo.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_elo.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_evo.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_evo.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_features.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_internal.h
Fix: SuperSlab guess loop & header magic SEGV (random_mixed/mid_large_mt)
2025-11-07 17:34:24 +09:00
hakmem_l25_pool.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_l25_pool.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_learn_log.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_learn_log.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_learner.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_learner.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_libc.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_mid_mt.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_mid_mt.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_p2.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_p2.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_policy.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_policy.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_pool.c
Phase 1: Box Theory refactoring + include reduction
2025-11-06 21:54:12 +09:00
hakmem_pool.c.bak2
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_pool.c.bak3
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_pool.c.refactored
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_pool.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_prof.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_prof.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_site_rules.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_site_rules.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_size_hist.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_size_hist.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_sizeclass_dist.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_sizeclass_dist.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_super_registry.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_super_registry.h
Tiny/SuperSlab: implement per-class registry optimization for fast refill scan
2025-11-05 17:02:31 +09:00
hakmem_sys.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_sys.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_syscall.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_syscall.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_alloc_new.inc
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_alloc_v3.inc
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_alloc.inc
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_assist.inc.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_background.inc
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_batch_refill.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_bg_bin.inc.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_bg_spill.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_bg_spill.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_bump.inc.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_config.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_config.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_drain_ema.inc.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_fastcache.inc.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_free.inc
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_free.inc.bak
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_hot_pop_v4.inc.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_hot_pop.inc.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_hotmag.inc.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_init.inc
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_intel.inc
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_lifecycle.inc
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_magazine.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_magazine.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_metadata.inc
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_mini_mag.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_query_api.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_query.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_refill_p0.inc.h
Fix: Active counter double-decrement in P0 batch refill (4T crash → stable)
2025-11-07 12:37:23 +09:00
hakmem_tiny_refill.inc.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_registry_api.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_registry.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_remote_target.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_remote_target.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_remote.inc
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_rss_api.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_rss.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_sfc.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_simple.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_simple.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_slab_mgmt.inc
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_slow.inc
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_smallmag.inc.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_ss_target.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_ss_target.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_stats_api.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_stats.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_stats.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_superslab.c
Fix: Move g_hakmem_lock_depth++ to function start (27% → 70% success)
2025-11-07 03:03:07 +09:00
hakmem_tiny_superslab.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny_tls_list.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_tls_ops.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_ultra_front.inc.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_tiny_ultra_simple.inc
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
hakmem_tiny.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_trace.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_ucb1.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_whale.c
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem_whale.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
hakmem.c
Fix: LIBC/HAKMEM mixed allocation crashes (0% → 80% success)
2025-11-07 02:48:20 +09:00
hakmem.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
mid_tcache.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
slab_handle.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_alloc_fast_sfc.inc.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_alloc_fast.inc.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_api.h
Phase 1: Box Theory refactoring + include reduction
2025-11-06 21:54:12 +09:00
tiny_atomic.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
tiny_debug_ring.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_debug_ring.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_debug.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
tiny_fastcache.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_fastcache.h
Phase 6-8: RDTSC cycle profiling - Critical bottleneck discovered!
2025-11-05 05:44:18 +00:00
tiny_free_fast.inc.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_free_magazine.inc.h
Phase 1: Box Theory refactoring + include reduction
2025-11-06 21:54:12 +09:00
tiny_mmap_gate.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_publish.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_publish.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
tiny_ready_bg.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_ready.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_refill_opt.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_refill.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_remote_bg.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_remote.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_remote.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
tiny_route.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_sticky.c
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_sticky.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
tiny_superslab_alloc.inc.h
Phase 1: Box Theory refactoring + include reduction
2025-11-06 21:54:12 +09:00
tiny_superslab_free.inc.h
CRITICAL FIX: TLS 未初期化による 4T SEGV を完全解消
2025-11-07 01:27:04 +09:00
tiny_system.h
Phase 1: Box Theory refactoring + include reduction
2025-11-06 21:54:12 +09:00
tiny_tls_guard.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00
tiny_tls.h
Debug Counters Implementation - Clean History
2025-11-05 12:31:14 +09:00