From 6d06bc83a5ae8777a5f7a81c32dd75b8d9b2fe04 Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky Date: Thu, 29 Jan 2026 12:10:30 +0900 Subject: [PATCH] net: usb: r8152: fix resume reset deadlock rtl8152 can trigger device reset during reset which potentially can result in a deadlock: **** DPM device timeout after 10 seconds; 15 seconds until panic **** Call Trace: schedule+0x483/0x1370 schedule_preempt_disabled+0x15/0x30 __mutex_lock_common+0x1fd/0x470 __rtl8152_set_mac_address+0x80/0x1f0 dev_set_mac_address+0x7f/0x150 rtl8152_post_reset+0x72/0x150 usb_reset_device+0x1d0/0x220 rtl8152_resume+0x99/0xc0 usb_resume_interface+0x3e/0xc0 usb_resume_both+0x104/0x150 usb_resume+0x22/0x110 The problem is that rtl8152 resume calls reset under tp->control mutex while reset basically re-enters rtl8152 and attempts to acquire the same tp->control lock once again. Reset INACCESSIBLE device outside of tp->control mutex scope to avoid recursive mutex_lock() deadlock. Fixes: 4933b066fefb ("r8152: If inaccessible at resume time, issue a reset") Reviewed-by: Douglas Anderson Signed-off-by: Sergey Senozhatsky Link: https://patch.msgid.link/20260129031106.3805887-1-senozhatsky@chromium.org Signed-off-by: Jakub Kicinski --- drivers/net/usb/r8152.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index fa5192583860..2f3baa5f6e9c 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -8535,19 +8535,6 @@ static int rtl8152_system_resume(struct r8152 *tp) usb_submit_urb(tp->intr_urb, GFP_NOIO); } - /* If the device is RTL8152_INACCESSIBLE here then we should do a - * reset. This is important because the usb_lock_device_for_reset() - * that happens as a result of usb_queue_reset_device() will silently - * fail if the device was suspended or if too much time passed. - * - * NOTE: The device is locked here so we can directly do the reset. - * We don't need usb_lock_device_for_reset() because that's just a - * wrapper over device_lock() and device_resume() (which calls us) - * does that for us. - */ - if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) - usb_reset_device(tp->udev); - return 0; } @@ -8658,19 +8645,33 @@ static int rtl8152_suspend(struct usb_interface *intf, pm_message_t message) static int rtl8152_resume(struct usb_interface *intf) { struct r8152 *tp = usb_get_intfdata(intf); + bool runtime_resume = test_bit(SELECTIVE_SUSPEND, &tp->flags); int ret; mutex_lock(&tp->control); rtl_reset_ocp_base(tp); - if (test_bit(SELECTIVE_SUSPEND, &tp->flags)) + if (runtime_resume) ret = rtl8152_runtime_resume(tp); else ret = rtl8152_system_resume(tp); mutex_unlock(&tp->control); + /* If the device is RTL8152_INACCESSIBLE here then we should do a + * reset. This is important because the usb_lock_device_for_reset() + * that happens as a result of usb_queue_reset_device() will silently + * fail if the device was suspended or if too much time passed. + * + * NOTE: The device is locked here so we can directly do the reset. + * We don't need usb_lock_device_for_reset() because that's just a + * wrapper over device_lock() and device_resume() (which calls us) + * does that for us. + */ + if (!runtime_resume && test_bit(RTL8152_INACCESSIBLE, &tp->flags)) + usb_reset_device(tp->udev); + return ret; } -- 2.47.3