From patchwork Wed Dec 27 02:59:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13505093 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) (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 13F6620E3; Wed, 27 Dec 2023 02:59:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="MRbt5+7u" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703645986; x=1735181986; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=UK9W7l9f1aXeh2OTEImTXTFv3TJOJuJ89xHyeun/tjE=; b=MRbt5+7uE3TUmfogdjHoq++atHGpP5m3K8wBc67fRzrKtqXcflTD2q5O a45OTNufEblvbe19kEHfQbj8CdX5Sb+MLTNjZYGjpUNoe1uvYmSsSLsh4 YkjRh8hKgwcbiovuJwQEol+SZgn+GEonjvHl/dlbTV9x3LLqQASidXhab NNSBorXZ7c5c1YJelUCHZYLyb8yDo+6ohj24YyJ54tU4rbQy8A5oMVJni v9ptyAUAQPG3E6K9AtoS84ghQd3V9c7jE/zgqak2HO+M03NumhTH4qVii AbeLdIduyZ0h3letLobdUV43Xe5mLAOPYfT5cIXZT7drWe8uMQwhGGj83 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10935"; a="3705785" X-IronPort-AV: E=Sophos;i="6.04,307,1695711600"; d="scan'208";a="3705785" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Dec 2023 18:59:35 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10935"; a="951386089" X-IronPort-AV: E=Sophos;i="6.04,307,1695711600"; d="scan'208";a="951386089" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by orsmga005.jf.intel.com with ESMTP; 26 Dec 2023 18:59:31 -0800 From: Ethan Zhao To: bhelgaas@google.com, baolu.lu@linux.intel.com, dwmw2@infradead.org, will@kernel.org, robin.murphy@arm.com, lukas@wunner.de Cc: linux-pci@vger.kernel.org, iommu@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [RFC PATCH v8 2/5] iommu/vt-d: break out device-TLB invalidation if target device is gone Date: Tue, 26 Dec 2023 21:59:20 -0500 Message-Id: <20231227025923.536148-3-haifeng.zhao@linux.intel.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20231227025923.536148-1-haifeng.zhao@linux.intel.com> References: <20231227025923.536148-1-haifeng.zhao@linux.intel.com> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 For those endpoint devices connect to system via hotplug capable ports, users could request a warm reset to the device by flapping device's link through setting the slot's link control register, as pciehp_ist() DLLSC interrupt sequence response, pciehp will unload the device driver and then power it off. thus cause an IOMMU device-TLB invalidation (Intel vt-d spec, or ATS invalidation in PCIe spec r6.1) request for device to be sent and a long time completion/timeout waiting in interrupt context. That would cause following continuous hard lockup warning and system hang [ 4211.433662] pcieport 0000:17:01.0: pciehp: Slot(108): Link Down [ 4211.433664] pcieport 0000:17:01.0: pciehp: Slot(108): Card not present [ 4223.822591] NMI watchdog: Watchdog detected hard LOCKUP on cpu 144 [ 4223.822622] CPU: 144 PID: 1422 Comm: irq/57-pciehp Kdump: loaded Tainted: G S OE kernel version xxxx [ 4223.822623] Hardware name: vendorname xxxx 666-106, BIOS 01.01.02.03.01 05/15/2023 [ 4223.822623] RIP: 0010:qi_submit_sync+0x2c0/0x490 [ 4223.822624] Code: 48 be 00 00 00 00 00 08 00 00 49 85 74 24 20 0f 95 c1 48 8b 57 10 83 c1 04 83 3c 1a 03 0f 84 a2 01 00 00 49 8b 04 24 8b 70 34 <40> f6 c6 1 0 74 17 49 8b 04 24 8b 80 80 00 00 00 89 c2 d3 fa 41 39 [ 4223.822624] RSP: 0018:ffffc4f074f0bbb8 EFLAGS: 00000093 [ 4223.822625] RAX: ffffc4f040059000 RBX: 0000000000000014 RCX: 0000000000000005 [ 4223.822625] RDX: ffff9f3841315800 RSI: 0000000000000000 RDI: ffff9f38401a8340 [ 4223.822625] RBP: ffff9f38401a8340 R08: ffffc4f074f0bc00 R09: 0000000000000000 [ 4223.822626] R10: 0000000000000010 R11: 0000000000000018 R12: ffff9f384005e200 [ 4223.822626] R13: 0000000000000004 R14: 0000000000000046 R15: 0000000000000004 [ 4223.822626] FS: 0000000000000000(0000) GS:ffffa237ae400000(0000) knlGS:0000000000000000 [ 4223.822627] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4223.822627] CR2: 00007ffe86515d80 CR3: 000002fd3000a001 CR4: 0000000000770ee0 [ 4223.822627] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4223.822628] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 [ 4223.822628] PKRU: 55555554 [ 4223.822628] Call Trace: [ 4223.822628] qi_flush_dev_iotlb+0xb1/0xd0 [ 4223.822628] __dmar_remove_one_dev_info+0x224/0x250 [ 4223.822629] dmar_remove_one_dev_info+0x3e/0x50 [ 4223.822629] intel_iommu_release_device+0x1f/0x30 [ 4223.822629] iommu_release_device+0x33/0x60 [ 4223.822629] iommu_bus_notifier+0x7f/0x90 [ 4223.822630] blocking_notifier_call_chain+0x60/0x90 [ 4223.822630] device_del+0x2e5/0x420 [ 4223.822630] pci_remove_bus_device+0x70/0x110 [ 4223.822630] pciehp_unconfigure_device+0x7c/0x130 [ 4223.822631] pciehp_disable_slot+0x6b/0x100 [ 4223.822631] pciehp_handle_presence_or_link_change+0xd8/0x320 [ 4223.822631] pciehp_ist+0x176/0x180 [ 4223.822631] ? irq_finalize_oneshot.part.50+0x110/0x110 [ 4223.822632] irq_thread_fn+0x19/0x50 [ 4223.822632] irq_thread+0x104/0x190 [ 4223.822632] ? irq_forced_thread_fn+0x90/0x90 [ 4223.822632] ? irq_thread_check_affinity+0xe0/0xe0 [ 4223.822633] kthread+0x114/0x130 [ 4223.822633] ? __kthread_cancel_work+0x40/0x40 [ 4223.822633] ret_from_fork+0x1f/0x30 [ 4223.822633] Kernel panic - not syncing: Hard LOCKUP [ 4223.822634] CPU: 144 PID: 1422 Comm: irq/57-pciehp Kdump: loaded Tainted: G S OE kernel version xxxx [ 4223.822634] Hardware name: vendorname xxxx 666-106, BIOS 01.01.02.03.01 05/15/2023 [ 4223.822634] Call Trace: [ 4223.822634] [ 4223.822635] dump_stack+0x6d/0x88 [ 4223.822635] panic+0x101/0x2d0 [ 4223.822635] ? ret_from_fork+0x11/0x30 [ 4223.822635] nmi_panic.cold.14+0xc/0xc [ 4223.822636] watchdog_overflow_callback.cold.8+0x6d/0x81 [ 4223.822636] __perf_event_overflow+0x4f/0xf0 [ 4223.822636] handle_pmi_common+0x1ef/0x290 [ 4223.822636] ? __set_pte_vaddr+0x28/0x40 [ 4223.822637] ? flush_tlb_one_kernel+0xa/0x20 [ 4223.822637] ? __native_set_fixmap+0x24/0x30 [ 4223.822637] ? ghes_copy_tofrom_phys+0x70/0x100 [ 4223.822637] ? __ghes_peek_estatus.isra.16+0x49/0xa0 [ 4223.822637] intel_pmu_handle_irq+0xba/0x2b0 [ 4223.822638] perf_event_nmi_handler+0x24/0x40 [ 4223.822638] nmi_handle+0x4d/0xf0 [ 4223.822638] default_do_nmi+0x49/0x100 [ 4223.822638] exc_nmi+0x134/0x180 [ 4223.822639] end_repeat_nmi+0x16/0x67 [ 4223.822639] RIP: 0010:qi_submit_sync+0x2c0/0x490 [ 4223.822639] Code: 48 be 00 00 00 00 00 08 00 00 49 85 74 24 20 0f 95 c1 48 8b 57 10 83 c1 04 83 3c 1a 03 0f 84 a2 01 00 00 49 8b 04 24 8b 70 34 <40> f6 c6 10 74 17 49 8b 04 24 8b 80 80 00 00 00 89 c2 d3 fa 41 39 [ 4223.822640] RSP: 0018:ffffc4f074f0bbb8 EFLAGS: 00000093 [ 4223.822640] RAX: ffffc4f040059000 RBX: 0000000000000014 RCX: 0000000000000005 [ 4223.822640] RDX: ffff9f3841315800 RSI: 0000000000000000 RDI: ffff9f38401a8340 [ 4223.822641] RBP: ffff9f38401a8340 R08: ffffc4f074f0bc00 R09: 0000000000000000 [ 4223.822641] R10: 0000000000000010 R11: 0000000000000018 R12: ffff9f384005e200 [ 4223.822641] R13: 0000000000000004 R14: 0000000000000046 R15: 0000000000000004 [ 4223.822641] ? qi_submit_sync+0x2c0/0x490 [ 4223.822642] ? qi_submit_sync+0x2c0/0x490 [ 4223.822642] [ 4223.822642] qi_flush_dev_iotlb+0xb1/0xd0 [ 4223.822642] __dmar_remove_one_dev_info+0x224/0x250 [ 4223.822643] dmar_remove_one_dev_info+0x3e/0x50 [ 4223.822643] intel_iommu_release_device+0x1f/0x30 [ 4223.822643] iommu_release_device+0x33/0x60 [ 4223.822643] iommu_bus_notifier+0x7f/0x90 [ 4223.822644] blocking_notifier_call_chain+0x60/0x90 [ 4223.822644] device_del+0x2e5/0x420 [ 4223.822644] pci_remove_bus_device+0x70/0x110 [ 4223.822644] pciehp_unconfigure_device+0x7c/0x130 [ 4223.822644] pciehp_disable_slot+0x6b/0x100 [ 4223.822645] pciehp_handle_presence_or_link_change+0xd8/0x320 [ 4223.822645] pciehp_ist+0x176/0x180 [ 4223.822645] ? irq_finalize_oneshot.part.50+0x110/0x110 [ 4223.822645] irq_thread_fn+0x19/0x50 [ 4223.822646] irq_thread+0x104/0x190 [ 4223.822646] ? irq_forced_thread_fn+0x90/0x90 [ 4223.822646] ? irq_thread_check_affinity+0xe0/0xe0 [ 4223.822646] kthread+0x114/0x130 [ 4223.822647] ? __kthread_cancel_work+0x40/0x40 [ 4223.822647] ret_from_fork+0x1f/0x30 [ 4223.822647] Kernel Offset: 0x6400000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) Furthermore even an in-process safe removal unplugged device could be surprise removed anytime, thus need to check the ATS invalidation target device state to see if it is gone, and don't wait for the completion/ timeout blindly, thus avoid the up to 1min+50% (see Implementation Note in PCIe spec r6.1 sec 10.3.1) waiting and cause hard lockup or system hang. Signed-off-by: Ethan Zhao --- drivers/iommu/intel/dmar.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index 23cb80d62a9a..76903a8bf963 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -1347,6 +1347,7 @@ int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc, unsigned int count, unsigned long options) { struct q_inval *qi = iommu->qi; + struct pci_dev *pdev = NULL; s64 devtlb_start_ktime = 0; s64 iotlb_start_ktime = 0; s64 iec_start_ktime = 0; @@ -1360,6 +1361,9 @@ int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc, if (!qi) return 0; + if (iommu->flush_target_dev && dev_is_pci(iommu->flush_target_dev)) + pdev = to_pci_dev(iommu->flush_target_dev); + type = desc->qw0 & GENMASK_ULL(3, 0); if ((type == QI_IOTLB_TYPE || type == QI_EIOTLB_TYPE) && @@ -1423,6 +1427,14 @@ int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc, writel(qi->free_head << shift, iommu->reg + DMAR_IQT_REG); while (qi->desc_status[wait_index] != QI_DONE) { + /* + * if the device-TLB invalidation target device is gone, don't + * wait anymore, it might take up to 1min+50%, causes system + * hang. (see Implementation Note in PCIe spec r6.1 sec 10.3.1) + */ + if ((type == QI_DIOTLB_TYPE || type == QI_DEIOTLB_TYPE) && pdev) + if (!pci_device_is_present(pdev)) + break; /* * We will leave the interrupts disabled, to prevent interrupt * context to queue another cmd while a cmd is already submitted