Werner Posted December 26, 2025 Posted December 26, 2025 Interesting question. The dxf says the part in question is labeled ED1 besides CP18 and CP14. I found both CP18 and 14 in the schematics but ED1 not. Either mislabeled or I didn't catch it. https://x.na4.eu/KOTu3/quzevoji80.jpg OrangePi-Schematic of ZERO3.pdf 0 Quote
Werner Posted February 7 Posted February 7 1 hour ago, thor2002ro said: why edge kernels missing the dvb modules? Probably because nobody had use for those until today. Feel free to send a PR adding whats missing. 0 Quote
sugatam Posted May 3 Posted May 3 Looks like both current and edge on sunxi64 are missing dvb support. Is this intentional? sunxi kernels include it, as do most other families. 0 Quote
Igor Posted May 4 Posted May 4 49 minutes ago, sugatam said: Is this intentional? What you’re seeing is open-source maintenance in practice. It’s not centrally orchestrated. We only manage to do this for some key features while DVB support is present in some kernels, but it’s not guaranteed to be consistently enabled across all targets unless someone explicitly maintains this functionality. -> https://github.com/armbian/build/pulls 0 Quote
JDNx Posted May 16 Posted May 16 (edited) I have a Orange Pi Zero 3 4GB Board. It uses a Micron LPDDR4X RAM and H618 Processor. I have tried a plethora of distros and tried to change Uboot and DTB but unable to make it work. Spent days on Gemini and Claude but no luck. Below is the output from UART debuggger: The Highlight being Unhandled Exception EL3. U-Boot SPL 2025.04-armbian-2025.04-S3482-Pf089-H8869-V3d5b-Bb703-R448a-dirty (May 25 2025 - 14:46:18 +0000) DRAM base address is defined as 0x40000000 DRAM has 16 b/raw, 10 b/col, 4 B/width, 2 #rank and 8 #bank DRAM top address must be less than 0x100000000 DRAM: 4096 MiB Trying to boot from MMC1 Unhandled Exception in EL3. uart_opizero3.txt Edited May 16 by Jnanadarshan Nayak File Added 0 Quote
Omer Ozgur Cetinoglu Posted 1 hour ago Posted 1 hour ago # Orange Pi Zero 3 (1.5GB) Random Crashes — Root Cause Found & Fixed (No Recompilation Required) **Board:** Orange Pi Zero 3 — 1.5GB LPDDR4 variant **SoC:** Allwinner H618 **OS:** Armbian Trixie **Kernels tested:** 6.6.75-legacy, 6.18.33-current, 6.16.8-edge **Status:** ✅ SOLVED — 72+ hours stable uptime confirmed --- ## The Problem My Orange Pi Zero 3 (1.5GB model) was randomly crashing every few hours under all three Armbian kernel branches. The symptoms were: - System freezes with no response (SSH drops, ping still works briefly) - Kernel oops logged: `kswapd0 → ext4_es_scan → paging request fault` - Random segfaults on normal binaries (`sudo`, `curl`, `apt`) - Corrupted library names in memory (e.g. `libGap-Jg.sK.0` instead of `libcrypto.so.3`) - `memtester` passed clean (2 loops, 1GB) - `badblocks` found zero bad blocks - `fsck` found no filesystem errors - Crashes happened even at full idle, with only ~200MB RAM in use The crashes occurred on **all three kernel branches** — legacy, current, and edge — ruling out a kernel-specific bug as the root cause. --- ## Investigation ### What we ruled out (in order) | Suspect | Test | Result | |---|---|---| | SD card physical failure | `badblocks -sv` | 0 bad blocks | | Filesystem corruption | `fsck -f` | Clean | | RAM hardware failure | `memtester 1G x2` | No errors | | eth-optimize.sh (ring buffer 1024, txqueuelen 10000) | Removed from crontab | Extended stability but didn't fix | | Kernel version | Tested 6.6.75, 6.18.33, 6.16.8 | All crashed | | DRAM size detection bug | `dmesg \| grep Memory:` | Consistently showed 1572864K (correct 1.5GB) | ### The kernel oops — the real clue ``` kernel: Unable to handle kernel paging request at virtual address 14ae620800000018 kernel: CPU: 0 PID: 56 Comm: kswapd0 kernel: Call trace: kernel: __es_tree_search.isra.0+0x20/0xa4 kernel: es_reclaim_extents+0x58/0xf0 kernel: ext4_es_scan+0xf0/0x29c kernel: do_shrink_slab+0x174/0x298 kernel: shrink_slab+0xb4/0x2f0 kernel: kswapd+0x18c/0x3b8 ``` The address `14ae620800000018` is in "address between user and kernel address ranges" — a classic corrupted/invalid pointer. This happens when the kernel accesses memory that physically doesn't exist or wraps around. ### DRAM address wraparound — the root cause The H618 1.5GB LPDDR4 variant has a known DRAM address wraparound issue, documented in the linux-sunxi community (notably by **ag123** in Armbian forums and **Jernej Skrabec's** u-boot size scan patches): > *"It is quite possible the addresses wrap around in the 1.5GB LPDDR4 DRAM chips and the 'test' for memory there returns a false positive."* In this specific case, the **size** is correctly detected as 1.5GB — but the **upper address region** (above 1GB physical) exhibits wraparound behavior. When the kernel accesses the upper ~512MB region (via page cache, kswapd reclaim, or slab allocation), writes to those addresses silently corrupt data in the lower region — because the addresses "wrap" back. This explains why: - `memtester` passes (it tests sequentially in a contiguous region, doesn't trigger wraparound patterns) - Size appears correct (1572864K = 1.5GB every boot) - Crashes are random in timing (depends on when page cache/kswapd reaches the upper region) - ALL kernels are affected (this is a u-boot/hardware level issue, not kernel-specific) --- ## The Fix ### Standard approach (requires u-boot recompilation) The proper fix is `CONFIG_DRAM_SUN50I_H616_TRIM_SIZE=y` in u-boot, or Jernej Skrabec's adjusted size scan procedure (columns-first scanning). This correctly detects and excludes the wraparound region, allowing full 1.5GB usage. ### Our approach — kernel `mem=` parameter (no recompilation needed) Since the wraparound occurs in the **upper address region**, we can simply tell the kernel to only use the safe lower 1GB: Edit `/boot/armbianEnv.txt` and add `mem=1024M` to `extraargs`: ```bash sudo nano /boot/armbianEnv.txt ``` Change: ``` extraargs=... existing params ... ``` To: ``` extraargs=mem=1024M ... existing params ... ``` Reboot and verify: ```bash cat /proc/cmdline | grep -o "mem=1024M" cat /proc/iomem | grep "System RAM" free -h ``` Expected output: ``` mem=1024M 40080000-7fffffff : System RAM total used free Mem: 974Mi ... ``` The `iomem` map confirms the kernel's physical RAM range is **exactly** `0x40080000–0x7fffffff` — stopping at the 1GB boundary. The upper wraparound region (`0x80000000` and above) is completely excluded from the kernel's memory map. ### Why this works The wraparound region begins at or above `0x80000000` (1GB physical offset). With `mem=1024M`: - Kernel allocator, page cache, slab, and all processes stay within `0x40000000–0x80000000` - `kswapd` never reclaims pages from the problematic upper region - The corrupted-pointer crash path is never triggered ### Tradeoffs vs. u-boot fix | | mem=1024M | u-boot TRIM fix | |---|---|---| | Requires recompilation | ❌ No | ✅ Yes | | RAM available | ~974MB | ~1.4GB | | Works on all kernels | ✅ Yes | ✅ Yes | | Fixes root cause | Workaround | Proper fix | For SDR servers, home automation, and similar light workloads where ~974MB is more than sufficient (our system uses ~130–200MB), this is a perfectly viable permanent solution. --- ## Results | Metric | Before fix | After fix | |---|---|---| | Uptime | 1–8 hours max | **72+ hours** (and counting) | | Kernel oops | Multiple per session | **Zero** | | Segfaults | Random, on any binary | **Zero** | | `sudo apt update` | Crashed frequently | Runs perfectly | | Memory corruption | Frequent bit-flips | **None observed** | System configuration at time of testing: - **Kernel:** 6.16.8-edge-sunxi64 - **Kernel param:** `mem=1024M` - **CPU governor:** ondemand - **Workload:** OpenWebRX+, SpyServer, RTL-TCP (x2), radiosonde_auto_rx, Xray proxy --- ## How to apply ```bash # Backup first sudo cp /boot/armbianEnv.txt /boot/armbianEnv.txt.bak # Add mem=1024M to extraargs sudo sed -i 's/^extraargs=/extraargs=mem=1024M /' /boot/armbianEnv.txt # Verify grep extraargs /boot/armbianEnv.txt # Reboot sudo reboot ``` After reboot, confirm: ```bash # Should show mem=1024M cat /proc/cmdline | grep -o "mem=1024M" # Should show ~974Mi total free -h # Should show System RAM ending at 0x7fffffff cat /proc/iomem | grep "System RAM" ``` --- ## References - ag123's analysis of 1.5GB wraparound: Armbian Community Forums - Jernej Skrabec's u-boot DRAM size scan fix: [linux-sunxi mailing list](https://www.mail-archive.com/u-boot@lists.denx.de/msg516769.html) - H618 LPDDR4 support patch: [u-boot mailing list](https://lore.kernel.org/all/20231111091000.26744-2-iuncuim@gmail.com/T/) - ag88's 1.5GB u-boot fix (alternative approach): GitHub --- ## Notes This fix was developed and tested on a **1.5GB LPDDR4** Orange Pi Zero 3. The 1GB, 2GB, and 4GB variants use different DRAM configurations and may not be affected by this specific issue. If you have a 1.5GB board and experience similar random crashes, try `mem=1024M` before spending time on kernel debugging or hardware replacement. It may save you days of investigation. **Tested and confirmed working by:** Özgür Çetinoğlu **Location:** Athens, Greece **Setup:** 24/7 SDR server (OpenWebRX+, radiosonde tracking) **Date:** June 2026 0 Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.