From c5e68706527968282e49de205cc2b935823cb88a Mon Sep 17 00:00:00 2001 From: Shivaprasad G Bhat Date: Tue, 14 Jul 2026 17:16:23 +0000 Subject: [PATCH] powerpc/eeh: Fix recursive locking on devices without EEH sensitive driver The commit 1010b4c012b0 ("powerpc/eeh: Make EEH driver device hotplug safe") refactored the EEH code such that the pci_rescan_remove_lock is held at the beginning of eeh_handle_normal_event() and the eeh_reset_device() is called with that lock being held. Looks like the commit missed to remove the existing lock/unlock inside eeh_rmv_device() which is no longer necessary. This is causing the eehd to hang on the lock which it actually holds when that code path is taken. [<0>] 0xc00000011c78f870 [<0>] __switch_to+0xfc/0x1a0 [<0>] pci_lock_rescan_remove+0x30/0x44 [<0>] eeh_rmv_device+0x290/0x2e0 [<0>] eeh_pe_dev_traverse+0x80/0x130 [<0>] eeh_reset_device+0xcc/0x23c [<0>] eeh_handle_normal_event+0x830/0xa80 [<0>] eeh_event_handler+0xf8/0x190 [<0>] kthread+0x194/0x1b0 [<0>] start_kernel_thread+0x14/0x18 The issue is seen for cases where the errors are detected on the PHB directly AND|OR for devices where the driver error_detected() returns PCI_ERS_RESULT_NEED_RESET, and driver being not EEH sensitive(i.e no error handlers like slot_reset(), resume() etc defined). Fixes: 1010b4c012b0 ("powerpc/eeh: Make EEH driver device hotplug safe") Cc: stable Reviewed-by: Ritesh Harjani (IBM) Signed-off-by: Shivaprasad G Bhat Reviewed-by: Amit Machhiwal Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/178404937381.913.2759874335293830160.stgit@linux.ibm.com --- arch/powerpc/kernel/eeh_driver.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c index 028f69158532..d64cce17a4e0 100644 --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -533,9 +533,7 @@ static void eeh_rmv_device(struct eeh_dev *edev, void *userdata) if (rmv_data) list_add(&edev->rmv_entry, &rmv_data->removed_vf_list); } else { - pci_lock_rescan_remove(); pci_stop_and_remove_bus_device(dev); - pci_unlock_rescan_remove(); } }