Subject: [PATCH] net: ethernet: ti: am65-cpsw: Fix segmentation fault at module unload

From: Roger Quadros <[email-masked]>
Date: Wed, 2 Nov 2022 12:31:44 +0200

Move am65_cpsw_nuss_phylink_cleanup() call to after
am65_cpsw_nuss_cleanup_ndev() so phylink is still valid
to prevent the below Segmentation fault on module remove when
first slave link is up.

[   31.652944] Unable to handle kernel paging request at virtual address 00040008000005f4
[   31.684627] Mem abort info:
[   31.687446]   ESR = 0x0000000096000004
[   31.704614]   EC = 0x25: DABT (current EL), IL = 32 bits
[   31.720663]   SET = 0, FnV = 0
[   31.723729]   EA = 0, S1PTW = 0
[   31.740617]   FSC = 0x04: level 0 translation fault
[   31.756624] Data abort info:
[   31.759508]   ISV = 0, ISS = 0x00000004
[   31.776705]   CM = 0, WnR = 0
[   31.779695] [00040008000005f4] address between user and kernel address ranges
[   31.808644] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[   31.814928] Modules linked in: wlcore_sdio wl18xx wlcore mac80211 libarc4 cfg80211 rfkill crct10dif_ce phy_gmii_sel ti_am65_cpsw_nuss(-) sch_fq_codel ipv6
[   31.828776] CPU: 0 PID: 1026 Comm: modprobe Not tainted 6.1.0-rc2-00012-gfabfcf7dafdb-dirty #160
[   31.837547] Hardware name: Texas Instruments AM625 (DT)
[   31.842760] pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   31.849709] pc : phy_stop+0x18/0xf8
[   31.853202] lr : phylink_stop+0x38/0xf8
[   31.857031] sp : ffff80000a0839f0
[   31.860335] x29: ffff80000a0839f0 x28: ffff000000de1c80 x27: 0000000000000000
[   31.867462] x26: 0000000000000000 x25: 0000000000000000 x24: ffff80000a083b98
[   31.874589] x23: 0000000000000800 x22: 0000000000000001 x21: ffff000001bfba90
[   31.881715] x20: ffff0000015ee000 x19: 0004000800000200 x18: 0000000000000000
[   31.888842] x17: ffff800076c45000 x16: ffff800008004000 x15: 000058e39660b106
[   31.895969] x14: 0000000000000144 x13: 0000000000000144 x12: 0000000000000000
[   31.903095] x11: 000000000000275f x10: 00000000000009e0 x9 : ffff80000a0837d0
[   31.910222] x8 : ffff000000de26c0 x7 : ffff00007fbd6540 x6 : ffff00007fbd64c0
[   31.917349] x5 : ffff00007fbd0b10 x4 : ffff00007fbd0b10 x3 : ffff00007fbd3920
[   31.924476] x2 : d0a07fcff8b8d500 x1 : 0000000000000000 x0 : 0004000800000200
[   31.931603] Call trace:
[   31.934042]  phy_stop+0x18/0xf8
[   31.937177]  phylink_stop+0x38/0xf8
[   31.940657]  am65_cpsw_nuss_ndo_slave_stop+0x28/0x1e0 [ti_am65_cpsw_nuss]
[   31.947452]  __dev_close_many+0xa4/0x140
[   31.951371]  dev_close_many+0x84/0x128
[   31.955115]  unregister_netdevice_many+0x130/0x6d0
[   31.959897]  unregister_netdevice_queue+0x94/0xd8
[   31.964591]  unregister_netdev+0x24/0x38
[   31.968504]  am65_cpsw_nuss_cleanup_ndev.isra.0+0x48/0x70 [ti_am65_cpsw_nuss]
[   31.975637]  am65_cpsw_nuss_remove+0x58/0xf8 [ti_am65_cpsw_nuss]

Cc: <[email-masked]> # v5.18+
Fixes: e8609e69470f ("net: ethernet: ti: am65-cpsw: Convert to PHYLINK")
Signed-off-by: Roger Quadros <[email-masked]>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 7f86068f3ff6..c50b137f92d7 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -2823,7 +2823,6 @@ static int am65_cpsw_nuss_remove(struct platform_device *pdev)
 	if (ret < 0)
 		return ret;
 
-	am65_cpsw_nuss_phylink_cleanup(common);
 	am65_cpsw_unregister_devlink(common);
 	am65_cpsw_unregister_notifiers(common);
 
@@ -2831,6 +2830,7 @@ static int am65_cpsw_nuss_remove(struct platform_device *pdev)
 	 * dma_deconfigure(dev) before devres_release_all(dev)
 	 */
 	am65_cpsw_nuss_cleanup_ndev(common);
+	am65_cpsw_nuss_phylink_cleanup(common);
 
 	of_platform_device_destroy(common->mdio_dev, NULL);
 
-- 
2.17.1