From patchwork Wed Dec 27 02:59:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13505094 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 A4F012109; Wed, 27 Dec 2023 02:59:46 +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="TWcnwNiV" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703645987; x=1735181987; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=6EZM0STQUmP7aVHDp+0lhBXnIJUofqomOyzh9k1hZec=; b=TWcnwNiV+ZP3Mq5SbeJLObdFKIO/FSkRxYnbsaHOKLqhl7LO9NdvEHkR NFlsGK9zbb/AWi39XShDy0j8A9no93e5mL70AsAw3y42fPB3/zSTlGkoY vlWbgsAdVJk2uR6cHiWiMvEEpy/uKED+ndeAvwno/lZAZVt+XYWWUklpE 3s/cOWU2t3LbQWw3w5E4GI79x2hcgU+WSBTyu+614EIWf4ns8Tg34rIpY V00GsxKUwCu7ZQ4wACYBJ+VOZvp9+0+/q2YegMGZnY4Orr8jkqnPp9BoP NNwgCAqjXz/zd96yzkmVZCRamW9rZFI1O/O16xfbVZPSN+ukCkTbG2sdq w==; X-IronPort-AV: E=McAfee;i="6600,9927,10935"; a="3705778" X-IronPort-AV: E=Sophos;i="6.04,307,1695711600"; d="scan'208";a="3705778" 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 18:59:32 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10935"; a="951386085" X-IronPort-AV: E=Sophos;i="6.04,307,1695711600"; d="scan'208";a="951386085" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by orsmga005.jf.intel.com with ESMTP; 26 Dec 2023 18:59:29 -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 1/5] iommu/vt-d: add flush_target_dev member to struct intel_iommu and pass device info to all ATS invalidation functions Date: Tue, 26 Dec 2023 21:59:19 -0500 Message-Id: <20231227025923.536148-2-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 As iommu is a pointer member of device_domain_info, so can't play trick like container_of() to get the info and device instance for qi_submit_sync() low level function to check device status, add a flush_target_dev member to struct inte_iommu and pass dev info to all device-TLB invalidation (a.k.a ATS invalidation) functions. Signed-off-by: Ethan Zhao --- drivers/iommu/intel/iommu.c | 1 + drivers/iommu/intel/iommu.h | 2 ++ drivers/iommu/intel/pasid.c | 1 + drivers/iommu/intel/svm.c | 1 + 4 files changed, 5 insertions(+) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 897159dba47d..c3724f1d86dc 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -1461,6 +1461,7 @@ static void __iommu_flush_dev_iotlb(struct device_domain_info *info, sid = info->bus << 8 | info->devfn; qdep = info->ats_qdep; + info->iommu->flush_target_dev = info->dev; qi_flush_dev_iotlb(info->iommu, sid, info->pfsid, qdep, addr, mask); quirk_extra_dev_tlb_flush(info, addr, mask, IOMMU_NO_PASID, qdep); diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index ce030c5b5772..e892c5c7560a 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -731,6 +731,8 @@ struct intel_iommu { void *perf_statistic; struct iommu_pmu *pmu; + + struct device *flush_target_dev; /* the target device TLB to be invalidated. */ }; /* PCI domain-device relationship */ diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index 74e8e4c17e81..1c87fb1b1039 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -485,6 +485,7 @@ devtlb_invalidation_with_pasid(struct intel_iommu *iommu, qdep = info->ats_qdep; pfsid = info->pfsid; + info->iommu->flush_target_dev = info->dev; /* * When PASID 0 is used, it indicates RID2PASID(DMA request w/o PASID), * devTLB flush w/o PASID should be used. For non-zero PASID under diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index ac12f76c1212..d42a99801cdf 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -181,6 +181,7 @@ static void __flush_svm_range_dev(struct intel_svm *svm, qi_flush_piotlb(sdev->iommu, sdev->did, svm->pasid, address, pages, ih); if (info->ats_enabled) { + info->iommu->flush_target_dev = info->dev; qi_flush_dev_iotlb_pasid(sdev->iommu, sdev->sid, info->pfsid, svm->pasid, sdev->qdep, address, order_base_2(pages)); 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 From patchwork Wed Dec 27 02:59:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13505095 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 F33002571; Wed, 27 Dec 2023 02:59:47 +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="TxCJI76J" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703645988; x=1735181988; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=hQnJp+eM13DOwyfJjWurrjBjS1JKHANOk6XIz1d/krs=; b=TxCJI76JWOGuzbkvyt77o1laF32Pa/CzRugbSS19NjhL0b0oesfZLrRi RaeyYJdmcGO4ReEeapAVj1O8TdiBXcq82YsxO7+JptJoDgkNMOz5BjBpf /JdTuW0HXAWD3jxtFAtVjVtIhCBNT58TThFs6UDbMZK7WC8hKERI+Y9kY ERdF62UP2rXKJvzcQP55dcT7NkzZPTATwN3d+L/mfwg+mW1li8Al884Q6 dBMHJKTCyIg42vFOZ2bfJpHGSrPhGfUi3b5B9YNm5v3oPL97FJeDMTBpT Zqzxipj0DGUHJdyB+nvq43Iq/ewHiyPr/jF/ZdJdsH9I72pwPiI05PLsd A==; X-IronPort-AV: E=McAfee;i="6600,9927,10935"; a="3705793" X-IronPort-AV: E=Sophos;i="6.04,307,1695711600"; d="scan'208";a="3705793" 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 18:59:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10935"; a="951386091" X-IronPort-AV: E=Sophos;i="6.04,307,1695711600"; d="scan'208";a="951386091" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by orsmga005.jf.intel.com with ESMTP; 26 Dec 2023 18:59:34 -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 3/5] PCI: make pci_dev_is_disconnected() helper public for other drivers Date: Tue, 26 Dec 2023 21:59:21 -0500 Message-Id: <20231227025923.536148-4-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 Make pci_dev_is_disconnected() public so that it can be called from Intel vt-d driver to quickly fix/workaround the surprise removal unplug hang issue for those ATS capable devices on PCIe switch downstream hotplug capable ports. Beside pci_device_is_present() function, this one has no config space space access, so is light enough to optimize the normal pure surprise removal and safe removal flow. Tested-by: Haorong Ye Signed-off-by: Ethan Zhao --- drivers/pci/pci.h | 5 ----- include/linux/pci.h | 5 +++++ 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 5ecbcf041179..75fa2084492f 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -366,11 +366,6 @@ static inline int pci_dev_set_disconnected(struct pci_dev *dev, void *unused) return 0; } -static inline bool pci_dev_is_disconnected(const struct pci_dev *dev) -{ - return dev->error_state == pci_channel_io_perm_failure; -} - /* pci_dev priv_flags */ #define PCI_DEV_ADDED 0 #define PCI_DPC_RECOVERED 1 diff --git a/include/linux/pci.h b/include/linux/pci.h index dea043bc1e38..4779eec8b267 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -2506,6 +2506,11 @@ static inline struct pci_dev *pcie_find_root_port(struct pci_dev *dev) return NULL; } +static inline bool pci_dev_is_disconnected(const struct pci_dev *dev) +{ + return dev->error_state == pci_channel_io_perm_failure; +} + void pci_request_acs(void); bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags); bool pci_acs_path_enabled(struct pci_dev *start, From patchwork Wed Dec 27 02:59:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13505096 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 6D8E13C0C; Wed, 27 Dec 2023 02:59:48 +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="KQzOWUTu" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703645989; x=1735181989; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=WG21CSSwsE/85hwPEnEufidCuVnAVIKF6sagH3cxk1U=; b=KQzOWUTuEGy9HQkXR0br008Pv+RjkzW+WXL4I/YPam1QR1Ru7PmDABCa dIZ8cStmlfZQef0Vhm14irrh47/oqXd7eGE6/mKrFVI9DNHnF8zpnFyOx 2LymV/XXhTwEmKxNtbtDkFjC/Fp90fgTvYjq/Rhkhqx/qUIbNZKHMgxH1 cN8EXtnkkQVrHyswuXQzOdIaNyEncP9L+wU6QAjTuIgad2UvW8rgH5vYQ lrL9LYD9vTxNJh+ppVQ5s1qh/XsdWJ4OlXIS/TYyJ18Io9xhTTmOd5RB8 yYYxvHFbu5rAbMQTOfJbmQ/ZUf00d2S4nNzD/NCNnl6HfD8AxOFLpgk8k A==; X-IronPort-AV: E=McAfee;i="6600,9927,10935"; a="3705805" X-IronPort-AV: E=Sophos;i="6.04,307,1695711600"; d="scan'208";a="3705805" 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 18:59:40 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10935"; a="951386099" X-IronPort-AV: E=Sophos;i="6.04,307,1695711600"; d="scan'208";a="951386099" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by orsmga005.jf.intel.com with ESMTP; 26 Dec 2023 18:59:37 -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 4/5] iommu/vt-d: don't issue device-TLB invalidate request when device is disconnected Date: Tue, 26 Dec 2023 21:59:22 -0500 Message-Id: <20231227025923.536148-5-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 Except those aggressive hotplug cases - surprise remove a hotplug device while its safe removal is requested and handled in process by: 1. pull it out directly. 2. turn off its power. 3. bring the link down. 4. just died there that moment. etc, in a word, 'gone' or 'disconnected'. Mostly are regular normal safe removal and surprise removal unplug. these hot unplug handling process could be optimized for fix the ATS invalidation hang issue by calling pci_dev_is_disconnected() in function devtlb_invalidation_with_pasid() to check target device state to avoid sending meaningless ATS invalidation request to iommu when device is gone. (see IMPLEMENTATION NOTE in PCIe spec r6.1 section 10.3.1) For safe removal, device wouldn't be removed untill the whole software handling process is done, it wouldn't trigger the hard lock up issue caused by too long ATS invalidation timeout wait. in safe removal path, device state isn't set to pci_channel_io_perm_failure in pciehp_unconfigure_device() by checking 'presence' parameter, calling pci_dev_is_disconnected() in devtlb_invalidation_with_pasid() will return false there, wouldn't break the function. For surprise removal, device state is set to pci_channel_io_perm_failure in pciehp_unconfigure_device(), means device is already gone (disconnected) call pci_dev_is_disconnected() in devtlb_invalidation_with_pasid() will return true to break the function not to send ATS invalidation request to the disconnected device blindly, thus avoid the further long time waiting triggers the hard lockup. safe removal & surprise removal pciehp_ist() pciehp_handle_presence_or_link_change() pciehp_disable_slot() remove_board() pciehp_unconfigure_device(presence) Tested-by: Haorong Ye Signed-off-by: Ethan Zhao --- drivers/iommu/intel/pasid.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index 1c87fb1b1039..a08bdbec90eb 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -481,6 +481,9 @@ devtlb_invalidation_with_pasid(struct intel_iommu *iommu, if (!info || !info->ats_enabled) return; + if (pci_dev_is_disconnected(to_pci_dev(dev))) + return; + sid = info->bus << 8 | info->devfn; qdep = info->ats_qdep; pfsid = info->pfsid; From patchwork Wed Dec 27 02:59:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13505097 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 A891B3C2C; Wed, 27 Dec 2023 02:59:48 +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="jsYNCPOh" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703645989; x=1735181989; 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26 Dec 2023 18:59:40 -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 5/5] iommu/vt-d: don't loop for timeout device-TLB invalidation request forever Date: Tue, 26 Dec 2023 21:59:23 -0500 Message-Id: <20231227025923.536148-6-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 When the device-TLB invalidation (ATS invalidation) timeout happens, the qi_submit_sync() will restart and loop for the invalidation request forever till it is done, it will block another invalidation thread such as the fq_timer to issue invalidation request, cause the system lockup as following [exception RIP: native_queued_spin_lock_slowpath+92] RIP: ffffffffa9d1025c RSP: ffffb202f268cdc8 RFLAGS: 00000002 RAX: 0000000000000101 RBX: ffffffffab36c2a0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffab36c2a0 RBP: ffffffffab36c2a0 R8: 0000000000000001 R9: 0000000000000000 R10: 0000000000000010 R11: 0000000000000018 R12: 0000000000000000 R13: 0000000000000004 R14: ffff9e10d71b1c88 R15: ffff9e10d71b1980 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 --- --- (the left part of exception see the hotplug case of ATS capable device) If one endpoint device just no response to the device-TLB invalidation request, but is not gone, it will bring down the whole system, to avoid such case, don't try the timeout device-TLB request forever. and as synchronous program model of current qi_submit_sync() implementation we couldn't wait for the enough time as PCIe spec said 1min+50%, just break it in current sync model. (PCIe spec r6.1, sec 10.3.1) Signed-off-by: Ethan Zhao --- drivers/iommu/intel/dmar.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index 76903a8bf963..206ab0b7294f 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -1457,7 +1457,7 @@ int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc, reclaim_free_desc(qi); raw_spin_unlock_irqrestore(&qi->q_lock, flags); - if (rc == -EAGAIN) + if (rc == -EAGAIN && type !=QI_DIOTLB_TYPE && type != QI_DEIOTLB_TYPE) goto restart; if (iotlb_start_ktime)