[PATCH RFC v2] e1000e: check reset_hw() return value in e1000_probe()

When forcing the e1000e driver to bind to an incompatible non-PCIe device
(such as the e1000 82540EM) via sysfs driver_override, a mismatch in
hardware register layouts occurs. This causes the driver to blindly retry
NVM reads and wait for a hardware response that never comes. When multiple
threads attempt this concurrently, they serialize on the device lock, and
the cumulative wait time easily exceeds the kernel's hung task timeout,
leading to a system crash:

INFO: task syz.2.41:7507 blocked for more than 143 seconds.
...
Call Trace:
 <TASK>
 __schedule+0x17e7/0x5630 kernel/sched/core.c:7234
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 device_lock include/linux/device.h:1104 [inline]
 __device_driver_lock drivers/base/dd.c:1171 [inline]
 device_driver_attach+0xd5/0x1d0 drivers/base/dd.c:1202
 bind_store+0x1d0/0x220 drivers/base/bus.c:267
...
NMI backtrace for cpu 1
...
RIP: 0010:e1000e_poll_eerd_eewr_done
drivers/net/ethernet/intel/e1000e/nvm.c:133 [inline]
RIP: 0010:e1000e_read_nvm_eerd+0xdf/0x300
drivers/net/ethernet/intel/e1000e/nvm.c:311
...
Call Trace:
 <TASK>
 e1000_read_nvm drivers/net/ethernet/intel/e1000e/e1000.h:588 [inline]
 e1000e_validate_nvm_checksum_generic+0xcb/0x3e0
 drivers/net/ethernet/intel/e1000e/nvm.c:553
 e1000_validate_nvm_checksum_82571+0x176/0x290
 drivers/net/ethernet/intel/e1000e/82571.c:787
 e1000_validate_nvm_checksum drivers/net/ethernet/intel/e1000e/e1000.h:577
 [inline]
 e1000_probe+0x12f8/0x2b20 drivers/net/ethernet/intel/e1000e/netdev.c:7590
 local_pci_probe drivers/pci/pci-driver.c:332 [inline]
 pci_call_probe drivers/pci/pci-driver.c:394 [inline]
 __pci_device_probe drivers/pci/pci-driver.c:455 [inline]
 pci_device_probe+0x431/0xc90 drivers/pci/pci-driver.c:489
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:706
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
 device_driver_attach+0xe0/0x1d0 drivers/base/dd.c:1203
 bind_store+0x1d0/0x220 drivers/base/bus.c:267

Fix this by checking the return value of adapter->hw.mac.ops.reset_hw() in
e1000_probe() and aborting the probe if it fails. This prevents the driver
from proceeding to the NVM checksum validation loop, which is responsible
for the massive delay.

Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver (currently for ICH9 devices only)")
Assisted-by: Gemini:gemini-3.6-flash Gemini:gemini-3.1-pro-preview syzbot
Reported-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=8ce4dba751e79facdc38
Link: https://syzkaller.appspot.com/ai_job?id=b99283dd-d283-4051-ad09-bed857e6c35f
To: "Andrew Lunn" <[email protected]>
To: "Tony Nguyen" <[email protected]>
To: "David S. Miller" <[email protected]>
To: "Eric Dumazet" <[email protected]>
To: <[email protected]>
To: "Jakub Kicinski" <[email protected]>
To: <[email protected]>
To: "Paolo Abeni" <[email protected]>
To: "Przemek Kitszel" <[email protected]>
To: "Auke Kok" <[email protected]>
Cc: <[email protected]>

---
v2:
- Removed pci_is_pcie() device check.
- Preserved original error code returned by reset_hw() instead of overriding with -EIO.

v1:
https://lore.kernel.org/all/[email protected]/T/
---
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 844f31ab3..ae287ed53 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -7581,7 +7581,11 @@ static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	/* before reading the NVM, reset the controller to
 	 * put the device in a known good starting state
 	 */
-	adapter->hw.mac.ops.reset_hw(&adapter->hw);
+	err = adapter->hw.mac.ops.reset_hw(&adapter->hw);
+	if (err) {
+		dev_err(&pdev->dev, "Hardware Error\n");
+		goto err_hw_init;
+	}
 
 	/* systems with ASPM and others may see the checksum fail on the first
 	 * attempt. Let's give it a few tries


base-commit: db2ddb87143519e20a95aa36c60b36107b736a58
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