From patchwork Thu Dec 28 17:02:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13506143 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (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 35408F9C2; Thu, 28 Dec 2023 17:02:16 +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="JQaN7dYI" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703782936; x=1735318936; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=wiw3f8LpISoCCs0eCxO8R6tIE4T0LHnT5p1cf2FrqlU=; b=JQaN7dYIn38u/I8AKFUNcPRATiQEM1DPbBU4VlicrKKMjGxT5IiswIKY X2jBCMO6xG1JsUvQK5VU+L6r0fZJEri3wL+3RtkVPe2Evx3oHpnTJPx9v d4s+dBP+D4RXVTrIU2KDZCJ6fBEd8j0OPOKQ7+Tp8FoXJcrJjJ5Kb6s0H sm0Eywl71yxTaTmgn8qnXUExGZlF+swZmjtbq304qtkyJLgiIsPE90oBL PcteBYcfuZ+thOu7XP/+GdrjGlF+/dxMSkb/5N/pNUNl4iMQqN3oBTkax 9lrY9ikiJP2jw8KuiN6Ne5mozc9zXOEiqJy6zdmaeoA+vWRe/vWBWNQG1 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="18119304" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="18119304" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Dec 2023 09:02:15 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="771757401" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="771757401" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by orsmga007.jf.intel.com with ESMTP; 28 Dec 2023 09:02:12 -0800 From: Ethan Zhao To: kevin.tian@intel.com, 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 v10 1/5] iommu/vt-d: add pci_dev parameter to qi_submit_sync and refactor callers Date: Thu, 28 Dec 2023 12:02:02 -0500 Message-Id: <20231228170206.720675-2-haifeng.zhao@linux.intel.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20231228170206.720675-1-haifeng.zhao@linux.intel.com> References: <20231228170206.720675-1-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 Signed-off-by: Ethan Zhao --- drivers/iommu/intel/dmar.c | 45 +++++++++++++++++++++-------- drivers/iommu/intel/iommu.c | 26 +++++------------ drivers/iommu/intel/iommu.h | 17 +++++------ drivers/iommu/intel/irq_remapping.c | 2 +- drivers/iommu/intel/pasid.c | 11 ++----- drivers/iommu/intel/svm.c | 13 ++++----- 6 files changed, 58 insertions(+), 56 deletions(-) diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index 23cb80d62a9a..3d661f2b7946 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -1344,7 +1344,7 @@ static int qi_check_fault(struct intel_iommu *iommu, int index, int wait_index) * can be part of the submission but it will not be polled for completion. */ int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc, - unsigned int count, unsigned long options) + unsigned int count, unsigned long options, struct pci_dev *pdev) { struct q_inval *qi = iommu->qi; s64 devtlb_start_ktime = 0; @@ -1476,7 +1476,7 @@ void qi_global_iec(struct intel_iommu *iommu) desc.qw3 = 0; /* should never fail */ - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, NULL); } void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm, @@ -1490,7 +1490,7 @@ void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm, desc.qw2 = 0; desc.qw3 = 0; - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, NULL); } void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr, @@ -1514,14 +1514,25 @@ void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr, desc.qw2 = 0; desc.qw3 = 0; - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, NULL); } -void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid, - u16 qdep, u64 addr, unsigned mask) +void qi_flush_dev_iotlb(struct intel_iommu *iommu, + struct device_domain_info *info, u64 addr, unsigned mask) { + struct pci_dev *pdev = NULL; + u16 sid, qdep, pfsid; struct qi_desc desc; + if (!info || !info->ats_enabled) + return; + + sid = info->bus << 8 | info->devfn; + qdep = info->ats_qdep; + pfsid = info->pfsid; + + if (dev_is_pci(info->dev)) + pdev = to_pci_dev(info->dev); /* * VT-d spec, section 4.3: * @@ -1545,7 +1556,7 @@ void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid, desc.qw2 = 0; desc.qw3 = 0; - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, pdev); } /* PASID-based IOTLB invalidation */ @@ -1586,16 +1597,26 @@ void qi_flush_piotlb(struct intel_iommu *iommu, u16 did, u32 pasid, u64 addr, QI_EIOTLB_AM(mask); } - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, NULL); } /* PASID-based device IOTLB Invalidate */ -void qi_flush_dev_iotlb_pasid(struct intel_iommu *iommu, u16 sid, u16 pfsid, - u32 pasid, u16 qdep, u64 addr, unsigned int size_order) +void qi_flush_dev_iotlb_pasid(struct intel_iommu *iommu, + struct device_domain_info *info, u64 addr, u32 pasid, + unsigned int size_order) { unsigned long mask = 1UL << (VTD_PAGE_SHIFT + size_order - 1); struct qi_desc desc = {.qw1 = 0, .qw2 = 0, .qw3 = 0}; + struct pci_dev *pdev = NULL; + u16 sid, qdep, pfsid; + + if (!info || !dev_is_pci(info->dev)) + return; + pdev = to_pci_dev(info->dev); + sid = info->bus << 8 | info->devfn; + qdep = info->ats_qdep; + pfsid = info->pfsid; /* * VT-d spec, section 4.3: * @@ -1639,7 +1660,7 @@ void qi_flush_dev_iotlb_pasid(struct intel_iommu *iommu, u16 sid, u16 pfsid, desc.qw1 |= QI_DEV_EIOTLB_SIZE; } - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, pdev); } void qi_flush_pasid_cache(struct intel_iommu *iommu, u16 did, @@ -1649,7 +1670,7 @@ void qi_flush_pasid_cache(struct intel_iommu *iommu, u16 did, desc.qw0 = QI_PC_PASID(pasid) | QI_PC_DID(did) | QI_PC_GRAN(granu) | QI_PC_TYPE; - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, NULL); } /* diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 897159dba47d..4dfbb493cd85 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -1454,16 +1454,11 @@ static void iommu_disable_pci_caps(struct device_domain_info *info) static void __iommu_flush_dev_iotlb(struct device_domain_info *info, u64 addr, unsigned int mask) { - u16 sid, qdep; - if (!info || !info->ats_enabled) return; - sid = info->bus << 8 | info->devfn; - qdep = info->ats_qdep; - qi_flush_dev_iotlb(info->iommu, sid, info->pfsid, - qdep, addr, mask); - quirk_extra_dev_tlb_flush(info, addr, mask, IOMMU_NO_PASID, qdep); + qi_flush_dev_iotlb(info->iommu, info, addr, mask); + quirk_extra_dev_tlb_flush(info, addr, IOMMU_NO_PASID, mask); } static void iommu_flush_dev_iotlb(struct dmar_domain *domain, @@ -1486,11 +1481,7 @@ static void iommu_flush_dev_iotlb(struct dmar_domain *domain, if (!info->ats_enabled) continue; - qi_flush_dev_iotlb_pasid(info->iommu, - PCI_DEVID(info->bus, info->devfn), - info->pfsid, dev_pasid->pasid, - info->ats_qdep, addr, - mask); + qi_flush_dev_iotlb_pasid(info->iommu, info, addr, dev_pasid->pasid, mask); } spin_unlock_irqrestore(&domain->lock, flags); } @@ -5183,9 +5174,8 @@ static void __init check_tylersburg_isoch(void) * * As a reminder, #6 will *NEED* this quirk as we enable nested translation. */ -void quirk_extra_dev_tlb_flush(struct device_domain_info *info, - unsigned long address, unsigned long mask, - u32 pasid, u16 qdep) +void quirk_extra_dev_tlb_flush(struct device_domain_info *info, u32 pasid, + unsigned long address, unsigned long mask) { u16 sid; @@ -5194,11 +5184,9 @@ void quirk_extra_dev_tlb_flush(struct device_domain_info *info, sid = PCI_DEVID(info->bus, info->devfn); if (pasid == IOMMU_NO_PASID) { - qi_flush_dev_iotlb(info->iommu, sid, info->pfsid, - qdep, address, mask); + qi_flush_dev_iotlb(info->iommu, info, address, mask); } else { - qi_flush_dev_iotlb_pasid(info->iommu, sid, info->pfsid, - pasid, qdep, address, mask); + qi_flush_dev_iotlb_pasid(info->iommu, info, address, pasid, mask); } } diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index ce030c5b5772..c19d93fd72e9 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -865,23 +865,22 @@ void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm, u64 type); void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr, unsigned int size_order, u64 type); -void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid, - u16 qdep, u64 addr, unsigned mask); +void qi_flush_dev_iotlb(struct intel_iommu *iommu, + struct device_domain_info *info, u64 addr, unsigned mask); void qi_flush_piotlb(struct intel_iommu *iommu, u16 did, u32 pasid, u64 addr, unsigned long npages, bool ih); -void qi_flush_dev_iotlb_pasid(struct intel_iommu *iommu, u16 sid, u16 pfsid, - u32 pasid, u16 qdep, u64 addr, - unsigned int size_order); -void quirk_extra_dev_tlb_flush(struct device_domain_info *info, - unsigned long address, unsigned long pages, - u32 pasid, u16 qdep); +void qi_flush_dev_iotlb_pasid(struct intel_iommu *iommu, + struct device_domain_info *info, u64 addr, u32 pasid, + unsigned int size_order); +void quirk_extra_dev_tlb_flush(struct device_domain_info *info, u32 pasid, + unsigned long address, unsigned long mask); void qi_flush_pasid_cache(struct intel_iommu *iommu, u16 did, u64 granu, u32 pasid); int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc, - unsigned int count, unsigned long options); + unsigned int count, unsigned long options, struct pci_dev *pdev); /* * Options used in qi_submit_sync: * QI_OPT_WAIT_DRAIN - Wait for PRQ drain completion, spec 6.5.2.8. diff --git a/drivers/iommu/intel/irq_remapping.c b/drivers/iommu/intel/irq_remapping.c index 29b9e55dcf26..f834afa3672d 100644 --- a/drivers/iommu/intel/irq_remapping.c +++ b/drivers/iommu/intel/irq_remapping.c @@ -153,7 +153,7 @@ static int qi_flush_iec(struct intel_iommu *iommu, int index, int mask) desc.qw2 = 0; desc.qw3 = 0; - return qi_submit_sync(iommu, &desc, 1, 0); + return qi_submit_sync(iommu, &desc, 1, 0, NULL); } static int modify_irte(struct irq_2_iommu *irq_iommu, diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index 74e8e4c17e81..715943531091 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -467,7 +467,7 @@ pasid_cache_invalidation_with_pasid(struct intel_iommu *iommu, desc.qw2 = 0; desc.qw3 = 0; - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, NULL); } static void @@ -475,16 +475,11 @@ devtlb_invalidation_with_pasid(struct intel_iommu *iommu, struct device *dev, u32 pasid) { struct device_domain_info *info; - u16 sid, qdep, pfsid; info = dev_iommu_priv_get(dev); if (!info || !info->ats_enabled) return; - sid = info->bus << 8 | info->devfn; - qdep = info->ats_qdep; - pfsid = info->pfsid; - /* * 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 @@ -492,9 +487,9 @@ devtlb_invalidation_with_pasid(struct intel_iommu *iommu, * efficient to flush devTLB specific to the PASID. */ if (pasid == IOMMU_NO_PASID) - qi_flush_dev_iotlb(iommu, sid, pfsid, qdep, 0, 64 - VTD_PAGE_SHIFT); + qi_flush_dev_iotlb(iommu, info, 0, 64 - VTD_PAGE_SHIFT); else - qi_flush_dev_iotlb_pasid(iommu, sid, pfsid, pasid, qdep, 0, 64 - VTD_PAGE_SHIFT); + qi_flush_dev_iotlb_pasid(iommu, info, 0, pasid, 64 - VTD_PAGE_SHIFT); } void intel_pasid_tear_down_entry(struct intel_iommu *iommu, struct device *dev, diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index ac12f76c1212..02719b96e6df 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -181,11 +181,10 @@ 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) { - qi_flush_dev_iotlb_pasid(sdev->iommu, sdev->sid, info->pfsid, - svm->pasid, sdev->qdep, address, + qi_flush_dev_iotlb_pasid(sdev->iommu, info, address, svm->pasid, + order_base_2(pages)); + quirk_extra_dev_tlb_flush(info, svm->pasid, address, order_base_2(pages)); - quirk_extra_dev_tlb_flush(info, address, order_base_2(pages), - svm->pasid, sdev->qdep); } } @@ -543,7 +542,7 @@ void intel_drain_pasid_prq(struct device *dev, u32 pasid) QI_DEV_IOTLB_PFSID(info->pfsid); qi_retry: reinit_completion(&iommu->prq_complete); - qi_submit_sync(iommu, desc, 3, QI_OPT_WAIT_DRAIN); + qi_submit_sync(iommu, desc, 3, QI_OPT_WAIT_DRAIN, NULL); if (readl(iommu->reg + DMAR_PRS_REG) & DMA_PRS_PRO) { wait_for_completion(&iommu->prq_complete); goto qi_retry; @@ -646,7 +645,7 @@ static void handle_bad_prq_event(struct intel_iommu *iommu, desc.qw3 = 0; } - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, NULL); } static irqreturn_t prq_event_thread(int irq, void *d) @@ -811,7 +810,7 @@ int intel_svm_page_response(struct device *dev, ktime_to_ns(ktime_get()) - prm->private_data[0]); } - qi_submit_sync(iommu, &desc, 1, 0); + qi_submit_sync(iommu, &desc, 1, 0, NULL); } out: return ret; From patchwork Thu Dec 28 17:02:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13506144 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (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 ECDF1101F0; Thu, 28 Dec 2023 17:02:18 +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="bMKcrAt5" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703782939; x=1735318939; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=1NSf/Rx7DQsEIxCh2UeVoLQRO8j5WXlSJXbU+JjGzVQ=; b=bMKcrAt5pfvLtmShmR/uDyofc1qbgS0hii7Ik7RDbEXGC2wWeeSJJX41 w94ECc0TIqMoiYotHG/CFsQO+e+vsvkunW/xVYEY70MI1Bxftt11CFPR9 Vct9iRr00xTuYR5p6tcrYz8log7GI3d9qm2LKEKsLUvWaNaQb+EmMh8hG TN6hGHmV21Z/jikYRGoh6Ds45Z9FqpbIVgxcjevimi3Vo7YhnbZbE/aIt Ba51CUJ0TfRRc7kpJEHOUHmKP+J3wubZLUxC2ue4kmleK+GkW8k1MNiSn aBi25YtB3wl4BlShQPuAfD/4bFIL3EcYjW2x8lPJEmypRXHciPMnBvdyz g==; X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="18119326" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="18119326" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Dec 2023 09:02:18 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="771757408" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="771757408" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by orsmga007.jf.intel.com with ESMTP; 28 Dec 2023 09:02:15 -0800 From: Ethan Zhao To: kevin.tian@intel.com, 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 v10 2/5] iommu/vt-d: break out ATS Invalidation if target device is gone Date: Thu, 28 Dec 2023 12:02:03 -0500 Message-Id: <20231228170206.720675-3-haifeng.zhao@linux.intel.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20231228170206.720675-1-haifeng.zhao@linux.intel.com> References: <20231228170206.720675-1-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 | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index 3d661f2b7946..0a8d628a42ee 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -1423,6 +1423,14 @@ 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 Thu Dec 28 17:05:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13506145 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (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 60B9710945; Thu, 28 Dec 2023 17:05:11 +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="YpaELrdB" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703783112; x=1735319112; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=1qBt4D1WArrSV0MOzrBsQzAWBORFHOsqP7rl6KWn9uo=; b=YpaELrdBRz9FfVAMKLP2WC3Qvzw4FMLoONJY697LpJorhvRxtETn8p/t 6A9XpowPVFgkSGgwQSLLAZNJpixU1hOjRATUPu/Trh+ndMaQqZnILCQOR neFUGJ4djx4jB5XIMmzJiAXMaSFQZBbOYGLfZP5uOqWHYFtdj3Abpmhy7 LkNQlYvSIpHXgoYik2iOzIhw3oSw94cmCqJS6ZBtFng4knhrGlStD+53k f1dOLSAEl9ha4ZZKUFtDoUuJrv13XfjWXlkd9EsWFtprfw96Eo7RFJI7g 0L/BSBNyoxjOdVjh13joy0KOW+LN2Y8ZizXfi7M8DCgs0O8trkfS5k0Iy w==; X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="10123448" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="10123448" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Dec 2023 09:05:11 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="848992439" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="848992439" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by fmsmga004.fm.intel.com with ESMTP; 28 Dec 2023 09:05:08 -0800 From: Ethan Zhao To: kevin.tian@intel.com, 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 v10 3/5] PCI: make pci_dev_is_disconnected() helper public for other drivers Date: Thu, 28 Dec 2023 12:05:02 -0500 Message-Id: <20231228170504.720794-1-haifeng.zhao@linux.intel.com> X-Mailer: git-send-email 2.31.1 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 Thu Dec 28 17:05:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13506146 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (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 D0F9CF9D7; Thu, 28 Dec 2023 17:05:13 +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="hftXHG8b" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703783114; x=1735319114; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=jlJA6l9/LxpjxQJJdNKaR0breVRQ2CVmXJiAZTX9pxk=; b=hftXHG8bJF8GVA/joG5fRsoTyXfHX6WCq1ckjlhodRXeobv9s4MKT+jm sHrFeAj3Ho+dfdn0cYWcpTaVLEfBhxLXQVov+mg3jRP3IUzsZ0Z0XXf1J HyYq7if6XR8GblY/lS1ZYrLoQ7oSDVJ9QlC/I95UZ3mHvWEGeCF6ijyDY Z2j2mCRy2aTqk/xF2ws6UhfcXF2jO1OYwiLM5MXA/KMbhyXOdPBDfRnEx +lAgNLb+jLzXDeOfzmGlatExGfMMVZnllM79FFQh8LMTPd46c0oe6H8zK 5H4YX5BMbEr5RrbGIf/ygQBV329Ts+NoW1PSFJXREyC+3c5Tih5AxGI4k Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="10123461" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="10123461" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Dec 2023 09:05:14 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="848992471" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="848992471" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by fmsmga004.fm.intel.com with ESMTP; 28 Dec 2023 09:05:10 -0800 From: Ethan Zhao To: kevin.tian@intel.com, 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 v10 4/5] iommu/vt-d: don't issue ATS Invalidation request when device is disconnected Date: Thu, 28 Dec 2023 12:05:03 -0500 Message-Id: <20231228170504.720794-2-haifeng.zhao@linux.intel.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20231228170504.720794-1-haifeng.zhao@linux.intel.com> References: <20231228170504.720794-1-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 | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index 715943531091..3d5ed27f39ef 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -480,6 +480,8 @@ devtlb_invalidation_with_pasid(struct intel_iommu *iommu, if (!info || !info->ats_enabled) return; + if (pci_dev_is_disconnected(to_pci_dev(dev))) + return; /* * 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 From patchwork Thu Dec 28 17:05:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ethan Zhao X-Patchwork-Id: 13506147 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (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 8F088101F8; Thu, 28 Dec 2023 17:05:16 +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="IZbZ+3dE" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703783117; x=1735319117; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Jb+k8qBAZn8bvLkpS7teeQRWVoilRckn2xon7o68bg0=; b=IZbZ+3dE3xMZ4S3gwR/awDmWE4JPqw1afQoV07tEgeRoYU204FRmO+f7 4Mg/JBS8ntPrTVp0GZQBDXcymhUleZ6Tavm6bBJxGmf/VlKZUhLL60WS9 f+6oQKd6xKhxaVRip073tShkxkiOYzgKxJ02iafrtGhQLHdg61QQBej8J 1UsCA7vQFQEMfrCbG6CH1OH6sO1k83OhE/N4JCMVDzl7TC9h3LIsajzIf HLMbrkt5DKh9py/mmBoP+e249PzfEp2Dpnos50hjKtXYPSUPvDZuSpkUM Itm/TEtqYLHn+811hFQSIlm9QKE2Cc3adHR/7NXIbHYBSKf2xHy+j/ZKN g==; X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="10123477" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="10123477" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Dec 2023 09:05:16 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="848992501" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="848992501" Received: from ply01-vm-store.bj.intel.com ([10.238.153.201]) by fmsmga004.fm.intel.com with ESMTP; 28 Dec 2023 09:05:13 -0800 From: Ethan Zhao To: kevin.tian@intel.com, 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 v10 5/5] iommu/vt-d: don't loop for timeout ATS Invalidation request forever Date: Thu, 28 Dec 2023 12:05:04 -0500 Message-Id: <20231228170504.720794-3-haifeng.zhao@linux.intel.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20231228170504.720794-1-haifeng.zhao@linux.intel.com> References: <20231228170504.720794-1-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 ATS Invalidation request 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 ATS Invalidation request, but is not gone, it will bring down the whole system, to avoid such case, don't try the timeout ATS Invalidation request forever. 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 0a8d628a42ee..9edb4b44afca 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -1453,7 +1453,7 @@ 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)