From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BA5E8347BBD; Wed, 30 Sep 2026 15:45:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790783133; cv=none; b=FFOCr1kcocA1+HEYlRO9UkK9VSUhJ1U7B9nxakiQD+28cJWUzbzepuOpuLeXZdi+crt61ZmsKqcHzq98coUZdcETOtmxb5N9Ev12PCG5/pgBgMfx2qzrWfBzfrRD5Vg8qduTnxyXm4DodtAdLVEhTvRk5G6+UbtiTbJ7/aO1Fs8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790783133; c=relaxed/simple; bh=z2V93wwfqs3yoXqZnFFhYQI8pgtyvq+c93LuNwuySN4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AE2LACRip3/G7EhHIHz14sJ10GqAszOntUjMoCZdsebqL6iuGqsKqtRkRlfsxIdnPDgOQSBjH15p39a81pEgIT8aQPhmSG20JUo2CPb0fiME0DAoxGNuDvv15IWJnw94rRQHma8r2K/GJKQ8AsDeN/H/qDqfF4PRJU96gRu0Iec= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BehmDeRY; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="BehmDeRY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A926C1F00898; Wed, 30 Sep 2026 15:45:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790783123; bh=QcDAEJX4AjDAmFooa7ASSZ+PGcDr2LB3xmtQEqKoEJE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BehmDeRYILFIKvfQZXSpU1Ef/zIN1P6GP3PvQXQtN6rP5yf8Y5Zf08RoFd/ki52WS Jbod02YDbqfcCohovMRnc2Z/CUFUPWww1iBT1u60981UCcykhJM8f3/XOwB6fQ2m33 3z7mgTvDNFy48YJ6VvaRdEiG8qJUOTUFdo/VLXb8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable , "Ritesh Harjani (IBM)" , Shivaprasad G Bhat , Amit Machhiwal , Madhavan Srinivasan Subject: [PATCH 5.10 287/595] powerpc/eeh: Fix recursive locking on devices without EEH sensitive driver Date: Wed, 30 Sep 2026 17:23:00 +0200 Message-ID: <20260930152353.871772018@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152347.700140858@linuxfoundation.org> References: <20260930152347.700140858@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shivaprasad G Bhat commit c5e68706527968282e49de205cc2b935823cb88a upstream. 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 Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/eeh_driver.c | 2 -- 1 file changed, 2 deletions(-) --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -534,9 +534,7 @@ static void eeh_rmv_device(struct eeh_de 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(); } }