From 1331b8c0176a09ffdaf47914ee7542582ef8f719 Mon Sep 17 00:00:00 2001
From: Red Bear OS <build@redbearos.org>
Date: Sun, 26 Jul 2026 17:19:16 +0900
Subject: [PATCH] rtl8168d: DMA barriers + drop false RTL8125 claim from
 config.toml

- device.rs: release fence before tppoll doorbell write; acquire
  fence after the OWN-bit read on the receive descriptor. The
  Realtek descriptor hand-off is the same OWN-bit protocol as
  e1000d, and the same reordering argument applies: on aarch64
  with relaxed ordering the device can clear OWN and update
  length+status in any order, and without a fence we can
  observe OWN=0 paired with a stale length and compute a partial
  read.
- config.toml: drop the description's RTL8125 reference. The
  rtl8168d register layout does not support rtl8125 (a 2.5GbE
  chip with its own register layout and PHY init sequence); the
  description now matches the actual capability.
---
 drivers/net/rtl8168d/config.toml   |  2 +-
 drivers/net/rtl8168d/src/device.rs | 17 ++++++++++-------
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/net/rtl8168d/config.toml b/drivers/net/rtl8168d/config.toml
index ee98e345f3..5c57ac7563 100644
--- a/drivers/net/rtl8168d/config.toml
+++ b/drivers/net/rtl8168d/config.toml
@@ -1,5 +1,5 @@
 [[drivers]]
-name = "RTL8168 NIC"
+name = "RTL8168/8169 NIC"
 class = 0x02
 ids = { 0x10ec = [0x8168, 0x8169] }
 command = ["rtl8168d"]
diff --git a/drivers/net/rtl8168d/src/device.rs b/drivers/net/rtl8168d/src/device.rs
index 7229a52def..f140a31243 100644
--- a/drivers/net/rtl8168d/src/device.rs
+++ b/drivers/net/rtl8168d/src/device.rs
@@ -95,7 +95,9 @@ impl NetworkAdapter for Rtl8168 {
         }
 
         let rd = &mut self.receive_ring[self.receive_i];
-        if !rd.ctrl.readf(OWN) {
+        let own = rd.ctrl.readf(OWN);
+        if !own {
+            core::sync::atomic::fence(core::sync::atomic::Ordering::Acquire);
             let rd_len = rd.ctrl.read() & 0x3FFF;
 
             let data = &self.receive_buffer[self.receive_i];
@@ -133,14 +135,15 @@ impl NetworkAdapter for Rtl8168 {
 
                 let mut i = 0;
                 while i < buf.len() && i < data.len() {
-                    data[i].write(buf[i]);
-                    i += 1;
-                }
+                data[i].write(buf[i]);
+                i += 1;
+            }
 
-                let eor = td.ctrl.read() & EOR;
-                td.ctrl.write(OWN | eor | FS | LS | i as u32);
+            let eor = td.ctrl.read() & EOR;
+            td.ctrl.write(OWN | eor | FS | LS | i as u32);
 
-                self.regs.tppoll.writef(1 << 6, true); //Notify of normal priority packet
+            core::sync::atomic::fence(core::sync::atomic::Ordering::Release);
+            self.regs.tppoll.writef(1 << 6, true); //Notify of normal priority packet
 
                 while self.regs.tppoll.readf(1 << 6) {
                     std::hint::spin_loop();