summaryrefslogtreecommitdiff
path: root/drivers/iommu/intel/dmar.c
AgeCommit message (Collapse)AuthorFilesLines
2026-08-11Merge branches 'arm/smmu/updates', 'arm/smmu/bindings', 'mediatek', ↵Joerg Roedel1-11/+87
'qualcomm/msm', 'rockchip', 'ti/omap', 'riscv', 'intel/vt-d', 'amd/amd-vi', 'core' and 'typos' into next
2026-08-10iommu/vt-d: Cache max domain ID to avoid redundant calculationLu Baolu1-0/+1
The cap_ndoms() helper calculates the maximum available domain ID from the value of capability register, which can be inefficient if called repeatedly. Cache the maximum supported domain ID in max_domain_id field during initialization to avoid redundant calls to cap_ndoms() throughout the IOMMU driver. No functionality change. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-08-10iommu/vt-d: Support the new DMA_REMAP_OPT_OUT flag bitKevin Tian1-10/+24
Some BIOS already provides config options to expose/hide VT-d units as a whole to/from system software. A new demand is to allow exposing VT-d units but requesting system software to disable DMA remapping while sustaining interrupt remapping. This can be communicated now by setting the new DMA_REMAP_OPT_OUT flag bit in the DMAR table, as introduced in VT-d spec v5.2 (section 8.1, DMA Remapping Reporting Structure). Introduce a new off policy (DMAR_FW_OFF) for DMA_REMAP_OPT_OUT. As the strongest off policy, it cannot be overridden by user opts or any force_on types. If tboot is enabled in the meantime, kernel will panic. It is user responsibility to configure BIOS properly. One cleanup is left for future - the DMAR flag is parsed multiple times, in detect_intel_iommu(), dmar_platform_optin() (which can be called at run-time), etc. Caching it is a cleaner way. Signed-off-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-08-10iommu/vt-d: Consolidate dmar policy management and force_on logicKevin Tian1-4/+54
Currently the dmar on/off is carried by multiple variables (no_iommu, dmar_disabled, no_platform_optin, etc.) with error-prone force_on logic scattered in multiple places. Unify/centralize the policy/priority management for various force_on scenarios. No functional impact except one case - "intel_iommu=off" sets no_platform_optin which is checked in platform_optin_force_iommu() but not in detect_intel_iommu(), leading to ACS unnecessarily requested when iommu could not be forced on later. Now with the unified logic this becomes more consistent. Signed-off-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-08-10iommu/vt-d: Force requesting ACS when tboot is enabledKevin Tian1-2/+13
Currently the conditions of requesting ACS in detect_intel_iommu() don't include tboot, leading to a possible misconfiguration with ACS disabled (e.g. due to user opts) while iommu is later forced on by tboot_force_iommu(). Fix it by checking tboot in detect_intel_iommu(). Fixes: 5d990b627537 ("PCI: add pci_request_acs") Cc: stable@vger.kernel.org Signed-off-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-07-22iommu/vt-d: Fix spelling of "guarantees" in commentxiongweimin1-1/+1
Correct "guarentees" to "guarantees" in the hotplug notes. Signed-off-by: xiongweimin <xiongweimin@kylinos.cn> Signed-off-by: Will Deacon <will@kernel.org>
2026-06-04iommu/vt-d: Improve IOMMU fault informationGuanghui Feng1-3/+6
In some environments, multiple PCIe segments exist, and PCIe device information needs to be differentiated and identified based on the segment. When an IOMMU fault event occurs, the IOMMU and device segment information should be output in detail in dmar_fault_do_one. Signed-off-by: Guanghui Feng <guanghuifeng@linux.alibaba.com> Link: https://lore.kernel.org/r/20260528022943.1697564-1-guanghuifeng@linux.alibaba.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-04-09Merge branches 'fixes', 'arm/smmu/updates', 'arm/smmu/bindings', 'riscv', ↵Will Deacon1-27/+16
'intel/vt-d', 'amd/amd-vi' and 'core' into next
2026-04-02iommu/vt-d: Split piotlb invalidation into range and allJason Gunthorpe1-15/+4
Currently these call chains are muddled up by using npages=-1, but only one caller has the possibility to do both options. Simplify qi_flush_piotlb() to qi_flush_piotlb_all() since all callers pass npages=-1. Split qi_batch_add_piotlb() into qi_batch_add_piotlb_all() and related helpers. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/1-v1-f175e27af136+11647-iommupt_inv_vtd_jgg@nvidia.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-04-02iommu/vt-d: Remove dmar_writel() and dmar_writeq()Bjorn Helgaas1-1/+1
dmar_writel() and dmar_writeq() do nothing other than expand to the generic writel() and writeq(), and the dmar_write*() wrappers are used inconsistently. Remove the dmar_write*() wrappers and use writel() and writeq() directly. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Samiullah Khawaja <skhawaja@google.com> Link: https://lore.kernel.org/r/20260217214438.3395039-3-bhelgaas@google.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-04-02iommu/vt-d: Remove dmar_readl() and dmar_readq()Bjorn Helgaas1-11/+11
dmar_readl() and dmar_readq() do nothing other than expand to the generic readl() and readq(), and the dmar_read*() wrappers are used inconsistently. Remove the dmar_read*() wrappers and use readl() and readq() directly. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Samiullah Khawaja <skhawaja@google.com> Link: https://lore.kernel.org/r/20260217214438.3395039-2-bhelgaas@google.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-03-17iommu/vt-d: Fix intel iommu iotlb sync hardlockup and retryGuanghui Feng1-2/+1
During the qi_check_fault process after an IOMMU ITE event, requests at odd-numbered positions in the queue are set to QI_ABORT, only satisfying single-request submissions. However, qi_submit_sync now supports multiple simultaneous submissions, and can't guarantee that the wait_desc will be at an odd-numbered position. Therefore, if an item times out, IOMMU can't re-initiate the request, resulting in an infinite polling wait. This modifies the process by setting the status of all requests already fetched by IOMMU and recorded as QI_IN_USE status (including wait_desc requests) to QI_ABORT, thus enabling multiple requests to be resubmitted. Fixes: 8a1d82462540 ("iommu/vt-d: Multiple descriptors per qi_submit_sync()") Cc: stable@vger.kernel.org Signed-off-by: Guanghui Feng <guanghuifeng@linux.alibaba.com> Tested-by: Shuai Xue <xueshuai@linux.alibaba.com> Reviewed-by: Shuai Xue <xueshuai@linux.alibaba.com> Reviewed-by: Samiullah Khawaja <skhawaja@google.com> Link: https://lore.kernel.org/r/20260306101516.3885775-1-guanghuifeng@linux.alibaba.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Fixes: 8a1d82462540 ("iommu/vt-d: Multiple descriptors per qi_submit_sync()") Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds1-2/+2
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook1-4/+4
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2025-07-14iommu/vt-d: Remove the CONFIG_X86 wrapping from iommu init hookVineeth Pillai (Google)1-3/+0
iommu init hook is wrapped in CONFI_X86 and is a remnant of dmar.c when it was a common code in "drivers/pci/dmar.c". This was added in commit (9d5ce73a64be2 x86: intel-iommu: Convert detect_intel_iommu to use iommu_init hook) Now this is built only for x86. This config wrap could be removed. Signed-off-by: Vineeth Pillai (Google) <vineeth@bitbyteword.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20250616131740.3499289-1-vineeth@bitbyteword.org Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20250714045028.958850-2-baolu.lu@linux.intel.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-23Merge branches 'fixes', 'apple/dart', 'arm/smmu/updates', ↵Joerg Roedel1-5/+9
'arm/smmu/bindings', 'fsl/pamu', 'mediatek', 'renesas/ipmmu', 's390', 'intel/vt-d', 'amd/amd-vi' and 'core' into next
2025-05-16iommu/vt-d: Replace spin_lock with mutex to protect domain idaLu Baolu1-0/+1
The domain ID allocator is currently protected by a spin_lock. However, ida_alloc_range can potentially block if it needs to allocate memory to grow its internal structures. Replace the spin_lock with a mutex which allows sleep on block. Thus, the memory allocation flags can be updated from GFP_ATOMIC to GFP_KERNEL to allow blocking memory allocations if necessary. Introduce a new mutex, did_lock, specifically for protecting the domain ida. The existing spinlock will remain for protecting other intel_iommu fields. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20250430021135.2370244-3-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-05-16iommu/vt-d: Use ida to manage domain idLu Baolu1-0/+3
Switch the intel iommu driver to use the ida mechanism for managing domain IDs, replacing the previous fixed-size bitmap. The previous approach allocated a bitmap large enough to cover the maximum number of domain IDs supported by the hardware, regardless of the actual number of domains in use. This led to unnecessary memory consumption, especially on systems supporting a large number of iommu units but only utilizing a small number of domain IDs. The ida allocator dynamically manages the allocation and freeing of integer IDs, only consuming memory for the IDs that are currently in use. This significantly optimizes memory usage compared to the fixed-size bitmap. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20250430021135.2370244-2-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-04-17iommu: Update various drivers to pass in lg2sz instead of order to iommu pagesJason Gunthorpe1-3/+3
Convert most of the places calling get_order() as an argument to the iommu-pages allocator into order_base_2() or the _sz flavour instead. These places already have an exact size, there is no particular reason to use order here. Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Tested-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/19-v4-c8663abbb606+3f7-iommu_pages_jgg@nvidia.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-04-17iommu/pages: Remove iommu_free_page()Jason Gunthorpe1-2/+2
Use iommu_free_pages() instead. Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Mostafa Saleh <smostafa@google.com> Tested-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/6-v4-c8663abbb606+3f7-iommu_pages_jgg@nvidia.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-02-28iommu/vt-d: Fix suspicious RCU usageLu Baolu1-0/+1
Commit <d74169ceb0d2> ("iommu/vt-d: Allocate DMAR fault interrupts locally") moved the call to enable_drhd_fault_handling() to a code path that does not hold any lock while traversing the drhd list. Fix it by ensuring the dmar_global_lock lock is held when traversing the drhd list. Without this fix, the following warning is triggered: ============================= WARNING: suspicious RCU usage 6.14.0-rc3 #55 Not tainted ----------------------------- drivers/iommu/intel/dmar.c:2046 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 1 2 locks held by cpuhp/1/23: #0: ffffffff84a67c50 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0 #1: ffffffff84a6a380 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0 stack backtrace: CPU: 1 UID: 0 PID: 23 Comm: cpuhp/1 Not tainted 6.14.0-rc3 #55 Call Trace: <TASK> dump_stack_lvl+0xb7/0xd0 lockdep_rcu_suspicious+0x159/0x1f0 ? __pfx_enable_drhd_fault_handling+0x10/0x10 enable_drhd_fault_handling+0x151/0x180 cpuhp_invoke_callback+0x1df/0x990 cpuhp_thread_fun+0x1ea/0x2c0 smpboot_thread_fn+0x1f5/0x2e0 ? __pfx_smpboot_thread_fn+0x10/0x10 kthread+0x12a/0x2d0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x4a/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Holding the lock in enable_drhd_fault_handling() triggers a lockdep splat about a possible deadlock between dmar_global_lock and cpu_hotplug_lock. This is avoided by not holding dmar_global_lock when calling iommu_device_register(), which initiates the device probe process. Fixes: d74169ceb0d2 ("iommu/vt-d: Allocate DMAR fault interrupts locally") Reported-and-tested-by: Ido Schimmel <idosch@nvidia.com> Closes: https://lore.kernel.org/linux-iommu/Zx9OwdLIc_VoQ0-a@shredder.mtl.com/ Tested-by: Breno Leitao <leitao@debian.org> Cc: stable@vger.kernel.org Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20250218022422.2315082-1-baolu.lu@linux.intel.com Tested-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-11-05iommu/vt-d: Remove unused dmar_msi_readDr. David Alan Gilbert1-13/+0
dmar_msi_read() has been unused since 2022 in commit cf8e8658100d ("arch: Remove Itanium (IA-64) architecture") Remove it. (dmar_msi_write still exists and is used once). Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Link: https://lore.kernel.org/r/20241022002702.302728-1-linux@treblig.org Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-11-05iommu/vt-d: Increase buffer size for device nameAndy Shevchenko1-1/+1
GCC is not happy with the current code, e.g.: .../iommu/intel/dmar.c:1063:9: note: ‘sprintf’ output between 6 and 15 bytes into a destination of size 13 1063 | sprintf(iommu->name, "dmar%d", iommu->seq_id); When `make W=1` is supplied, this prevents kernel building. Fix it by increasing the buffer size for device name and use sizeoF() instead of hard coded constants. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20241014104529.4025937-1-andriy.shevchenko@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-09-02iommu/vt-d: Factor out invalidation descriptor compositionTina Zhang1-87/+6
Separate the logic for constructing IOTLB and device TLB invalidation descriptors from the qi_flush interfaces. New helpers, qi_desc(), are introduced to encapsulate this common functionality. Moving descriptor composition code to new helpers enables its reuse in the upcoming qi_batch interfaces. No functional changes are intended. Signed-off-by: Tina Zhang <tina.zhang@intel.com> Link: https://lore.kernel.org/r/20240815065221.50328-2-tina.zhang@intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-09-02iommu/vt-d: Fix potential lockup if qi_submit_sync called with 0 countSanjay K Kumar1-5/+11
If qi_submit_sync() is invoked with 0 invalidation descriptors (for instance, for DMA draining purposes), we can run into a bug where a submitting thread fails to detect the completion of invalidation_wait. Subsequently, this led to a soft lockup. Currently, there is no impact by this bug on the existing users because no callers are submitting invalidations with 0 descriptors. This fix will enable future users (such as DMA drain) calling qi_submit_sync() with 0 count. Suppose thread T1 invokes qi_submit_sync() with non-zero descriptors, while concurrently, thread T2 calls qi_submit_sync() with zero descriptors. Both threads then enter a while loop, waiting for their respective descriptors to complete. T1 detects its completion (i.e., T1's invalidation_wait status changes to QI_DONE by HW) and proceeds to call reclaim_free_desc() to reclaim all descriptors, potentially including adjacent ones of other threads that are also marked as QI_DONE. During this time, while T2 is waiting to acquire the qi->q_lock, the IOMMU hardware may complete the invalidation for T2, setting its status to QI_DONE. However, if T1's execution of reclaim_free_desc() frees T2's invalidation_wait descriptor and changes its status to QI_FREE, T2 will not observe the QI_DONE status for its invalidation_wait and will indefinitely remain stuck. This soft lockup does not occur when only non-zero descriptors are submitted.In such cases, invalidation descriptors are interspersed among wait descriptors with the status QI_IN_USE, acting as barriers. These barriers prevent the reclaim code from mistakenly freeing descriptors belonging to other submitters. Considered the following example timeline: T1 T2 ======================================== ID1 WD1 while(WD1!=QI_DONE) unlock lock WD1=QI_DONE* WD2 while(WD2!=QI_DONE) unlock lock WD1==QI_DONE? ID1=QI_DONE WD2=DONE* reclaim() ID1=FREE WD1=FREE WD2=FREE unlock soft lockup! T2 never sees QI_DONE in WD2 Where: ID = invalidation descriptor WD = wait descriptor * Written by hardware The root of the problem is that the descriptor status QI_DONE flag is used for two conflicting purposes: 1. signal a descriptor is ready for reclaim (to be freed) 2. signal by the hardware that a wait descriptor is complete The solution (in this patch) is state separation by using QI_FREE flag for #1. Once a thread's invalidation descriptors are complete, their status would be set to QI_FREE. The reclaim_free_desc() function would then only free descriptors marked as QI_FREE instead of those marked as QI_DONE. This change ensures that T2 (from the previous example) will correctly observe the completion of its invalidation_wait (marked as QI_DONE). Signed-off-by: Sanjay K Kumar <sanjay.k.kumar@intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20240728210059.1964602-1-jacob.jun.pan@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-07-03iommu/vt-d: Handle volatile descriptor status readJacob Pan1-1/+1
Queued invalidation wait descriptor status is volatile in that IOMMU hardware writes the data upon completion. Use READ_ONCE() to prevent compiler optimizations which ensures memory reads every time. As a side effect, READ_ONCE() also enforces strict types and may add an extra instruction. But it should not have negative performance impact since we use cpu_relax anyway and the extra time(by adding an instruction) may allow IOMMU HW request cacheline ownership easier. e.g. gcc 12.3 BEFORE: 81 38 ad de 00 00 cmpl $0x2,(%rax) AFTER (with READ_ONCE()) 772f: 8b 00 mov (%rax),%eax 7731: 3d ad de 00 00 cmp $0x2,%eax //status data is 32 bit Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Yi Liu <yi.l.liu@intel.com> Link: https://lore.kernel.org/r/20240607173817.3914600-1-jacob.jun.pan@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20240702130839.108139-2-baolu.lu@linux.intel.com Signed-off-by: Will Deacon <will@kernel.org>
2024-05-13Merge branches 'arm/renesas', 'arm/smmu', 'x86/amd', 'core' and 'x86/vt-d' ↵Joerg Roedel1-10/+16
into next
2024-04-26iommu/vt-d: Allocate DMAR fault interrupts locallyDimitri Sivanich1-2/+7
The Intel IOMMU code currently tries to allocate all DMAR fault interrupt vectors on the boot cpu. On large systems with high DMAR counts this results in vector exhaustion, and most of the vectors are not initially allocated socket local. Instead, have a cpu on each node do the vector allocation for the DMARs on that node. The boot cpu still does the allocation for its node during its boot sequence. Signed-off-by: Dimitri Sivanich <sivanich@hpe.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/Zfydpp2Hm+as16TY@hpe.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-04-26iommu/vt-d: Remove redundant assignment to variable errColin Ian King1-1/+0
Variable err is being assigned a value that is never read. It is either being re-assigned later on error exit paths, or never referenced on the non-error path. Cleans up clang scan build warning: drivers/iommu/intel/dmar.c:1070:2: warning: Value stored to 'err' is never read [deadcode.DeadStores]` Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Link: https://lore.kernel.org/r/20240411090535.306326-1-colin.i.king@gmail.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-04-15iommu/vt-d: add wrapper functions for page allocationsPasha Tatashin1-7/+9
In order to improve observability and accountability of IOMMU layer, we must account the number of pages that are allocated by functions that are calling directly into buddy allocator. This is achieved by first wrapping the allocation related functions into a separate inline functions in new file: drivers/iommu/iommu-pages.h Convert all page allocation calls under iommu/intel to use these new functions. Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: David Rientjes <rientjes@google.com> Tested-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20240413002522.1101315-2-pasha.tatashin@soleen.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-03-06iommu/vt-d: Improve ITE fault handling if target device isn't presentEthan Zhao1-0/+22
Because surprise removal could happen anytime, e.g. user could request safe removal to EP(endpoint device) via sysfs and brings its link down to do surprise removal cocurrently. such aggressive cases would cause ATS invalidation request issued to non-existence target device, then deadly loop to retry that request after ITE fault triggered in interrupt context. this patch aims to optimize the ITE handling by checking the target device presence state to avoid retrying the timeout request blindly, thus avoid hard lockup or system hang. Devices TLB should only be invalidated when devices are in the iommu->device_rbtree (probed, not released) and present. Fixes: 6ba6c3a4cacf ("VT-d: add device IOTLB invalidation support") Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Ethan Zhao <haifeng.zhao@linux.intel.com> Link: https://lore.kernel.org/r/20240301080727.3529832-4-haifeng.zhao@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-03-01iommu/vt-d: Use device rbtree in iopf reporting pathLu Baolu1-0/+1
The existing I/O page fault handler currently locates the PCI device by calling pci_get_domain_bus_and_slot(). This function searches the list of all PCI devices until the desired device is found. To improve lookup efficiency, replace it with device_rbtree_find() to search the device within the probed device rbtree. The I/O page fault is initiated by the device, which does not have any synchronization mechanism with the software to ensure that the device stays in the probed device tree. Theoretically, a device could be released by the IOMMU subsystem after device_rbtree_find() and before iopf_get_dev_fault_param(), which would cause a use-after-free problem. Add a mutex to synchronize the I/O page fault reporting path and the IOMMU release device path. This lock doesn't introduce any performance overhead, as the conflict between I/O page fault reporting and device releasing is very rare. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20240220065939.121116-3-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-03-01iommu/vt-d: Use rbtree to track iommu probed devicesLu Baolu1-1/+2
Use a red-black tree(rbtree) to track devices probed by the driver's probe_device callback. These devices need to be looked up quickly by a source ID when the hardware reports a fault, either recoverable or unrecoverable. Fault reporting paths are critical. Searching a list in this scenario is inefficient, with an algorithm complexity of O(n). An rbtree is a self-balancing binary search tree, offering an average search time complexity of O(log(n)). This significant performance improvement makes rbtrees a better choice. Furthermore, rbtrees are implemented on a per-iommu basis, eliminating the need for global searches and further enhancing efficiency in critical fault paths. The rbtree is protected by a spin lock with interrupts disabled to ensure thread-safe access even within interrupt contexts. Co-developed-by: Huang Jiaqing <jiaqing.huang@intel.com> Signed-off-by: Huang Jiaqing <jiaqing.huang@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20240220065939.121116-2-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-11-27iommu/vt-d: Omit devTLB invalidation requests when TES=0Lu Baolu1-0/+18
The latest VT-d spec indicates that when remapping hardware is disabled (TES=0 in Global Status Register), upstream ATS Invalidation Completion requests are treated as UR (Unsupported Request). Consequently, the spec recommends in section 4.3 Handling of Device-TLB Invalidations that software refrain from submitting any Device-TLB invalidation requests when address remapping hardware is disabled. Verify address remapping hardware is enabled prior to submitting Device- TLB invalidation requests. Fixes: 792fb43ce2c9 ("iommu/vt-d: Enable Intel IOMMU scalable mode by default") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20231114011036.70142-2-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-04-14Merge branches 'iommu/fixes', 'arm/allwinner', 'arm/exynos', 'arm/mediatek', ↵Joerg Roedel1-8/+5
'arm/omap', 'arm/renesas', 'arm/rockchip', 'arm/smmu', 'ppc/pamu', 'unisoc', 'x86/vt-d', 'x86/amd', 'core' and 'platform-remove_new' into next
2023-04-13iommu/vt-d: Remove BUG_ON in dmar_insert_dev_scope()Tina Zhang1-1/+2
The dmar_insert_dev_scope() could fail if any unexpected condition is encountered. However, in this situation, the kernel should attempt recovery and proceed with execution. Remove BUG_ON with WARN_ON, so that kernel can avoid being crashed when an unexpected condition occurs. Signed-off-by: Tina Zhang <tina.zhang@intel.com> Link: https://lore.kernel.org/r/20230406065944.2773296-8-tina.zhang@intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-04-13iommu/vt-d: Remove a useless BUG_ON(dev->is_virtfn)Tina Zhang1-2/+0
When dmar_alloc_pci_notify_info() is being invoked, the invoker has ensured the dev->is_virtfn is false. So, remove the useless BUG_ON in dmar_alloc_pci_notify_info(). Signed-off-by: Tina Zhang <tina.zhang@intel.com> Link: https://lore.kernel.org/r/20230406065944.2773296-7-tina.zhang@intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-04-13iommu/vt-d: Make size of operands same in bitwise operationsTina Zhang1-1/+1
This addresses the following issue reported by klocwork tool: - operands of different size in bitwise operations Suggested-by: Yongwei Ma <yongwei.ma@intel.com> Signed-off-by: Tina Zhang <tina.zhang@intel.com> Link: https://lore.kernel.org/r/20230406065944.2773296-2-tina.zhang@intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-03-31iommu/vt-d: Allow zero SAGAW if second-stage not supportedLu Baolu1-1/+2
The VT-d spec states (in section 11.4.2) that hardware implementations reporting second-stage translation support (SSTS) field as Clear also report the SAGAW field as 0. Fix an inappropriate check in alloc_iommu(). Fixes: 792fb43ce2c9 ("iommu/vt-d: Enable Intel IOMMU scalable mode by default") Suggested-by: Raghunathan Srinivasan <raghunathan.srinivasan@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20230318024824.124542-1-baolu.lu@linux.intel.com Link: https://lore.kernel.org/r/20230329134721.469447-3-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-03-31iommu/ioasid: Rename INVALID_IOASIDJacob Pan1-2/+2
INVALID_IOASID and IOMMU_PASID_INVALID are duplicated. Rename INVALID_IOASID and consolidate since we are moving away from IOASID infrastructure. Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Link: https://lore.kernel.org/r/20230322200803.869130-7-jacob.jun.pan@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-03-31iommu/vt-d: Remove virtual command interfaceJacob Pan1-2/+0
Virtual command interface was introduced to allow using host PASIDs inside VMs. It is unused and abandoned due to architectural change. With this patch, we can safely remove this feature and the related helpers. Link: https://lore.kernel.org/r/20230210230206.3160144-2-jacob.jun.pan@linux.intel.com Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20230322200803.869130-2-jacob.jun.pan@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-02-03iommu/vt-d: Enable IOMMU perfmon supportKan Liang1-0/+3
Register and enable an IOMMU perfmon for each active IOMMU device. The failure of IOMMU perfmon registration doesn't impact other functionalities of an IOMMU device. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20230128200428.1459118-8-kan.liang@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-02-03iommu/vt-d: Add IOMMU perfmon overflow handler supportKan Liang1-0/+2
While enabled to count events and an event occurrence causes the counter value to increment and roll over to or past zero, this is termed a counter overflow. The overflow can trigger an interrupt. The IOMMU perfmon needs to handle the case properly. New HW IRQs are allocated for each IOMMU device for perfmon. The IRQ IDs are after the SVM range. In the overflow handler, the counter is not frozen. It's very unlikely that the same counter overflows again during the period. But it's possible that other counters overflow at the same time. Read the overflow register at the end of the handler and check whether there are more. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20230128200428.1459118-7-kan.liang@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-02-03iommu/vt-d: Support Enhanced Command InterfaceKan Liang1-0/+10
The Enhanced Command Register is to submit command and operand of enhanced commands to DMA Remapping hardware. It can supports up to 256 enhanced commands. There is a HW register to indicate the availability of all 256 enhanced commands. Each bit stands for each command. But there isn't an existing interface to read/write all 256 bits. Introduce the u64 ecmdcap[4] to store the existence of each enhanced command. Read 4 times to get all of them in map_iommu(). Add a helper to facilitate an enhanced command launch. Make sure hardware complete the command. Also add a helper to facilitate the check of PMU essentials. These helpers will be used later. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20230128200428.1459118-4-kan.liang@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-02-03iommu/vt-d: Retrieve IOMMU perfmon capability informationKan Liang1-0/+7
The performance monitoring infrastructure, perfmon, is to support collection of information about key events occurring during operation of the remapping hardware, to aid performance tuning and debug. Each remapping hardware unit has capability registers that indicate support for performance monitoring features and enumerate the capabilities. Add alloc_iommu_pmu() to retrieve IOMMU perfmon capability information for each iommu unit. The information is stored in the iommu->pmu data structure. Capability registers are read-only, so it's safe to prefetch and store them in the pmu structure. This could avoid unnecessary VMEXIT when this code is running in the virtualization environment. Add free_iommu_pmu() to free the saved capability information when freeing the iommu unit. Add a kernel config option for the IOMMU perfmon feature. Unless a user explicitly uses the perf tool to monitor the IOMMU perfmon event, there isn't any impact for the existing IOMMU. Enable it by default. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20230128200428.1459118-3-kan.liang@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-02-03iommu/vt-d: Support size of the register set in DRHDKan Liang1-4/+7
A new field, which indicates the size of the remapping hardware register set for this remapping unit, is introduced in the DMA-remapping hardware unit definition (DRHD) structure with the VT-d Spec 4.0. With this information, SW doesn't need to 'guess' the size of the register set anymore. Update the struct acpi_dmar_hardware_unit to reflect the field. Store the size of the register set in struct dmar_drhd_unit for each dmar device. The 'size' information is ResvZ for the old BIOS and platforms. Fall back to the old guessing method. There is nothing changed. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20230128200428.1459118-2-kan.liang@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2022-12-14Merge tag 'for-linus-iommufd' of ↵Linus Torvalds1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd Pull iommufd implementation from Jason Gunthorpe: "iommufd is the user API to control the IOMMU subsystem as it relates to managing IO page tables that point at user space memory. It takes over from drivers/vfio/vfio_iommu_type1.c (aka the VFIO container) which is the VFIO specific interface for a similar idea. We see a broad need for extended features, some being highly IOMMU device specific: - Binding iommu_domain's to PASID/SSID - Userspace IO page tables, for ARM, x86 and S390 - Kernel bypassed invalidation of user page tables - Re-use of the KVM page table in the IOMMU - Dirty page tracking in the IOMMU - Runtime Increase/Decrease of IOPTE size - PRI support with faults resolved in userspace Many of these HW features exist to support VM use cases - for instance the combination of PASID, PRI and Userspace IO Page Tables allows an implementation of DMA Shared Virtual Addressing (vSVA) within a guest. Dirty tracking enables VM live migration with SRIOV devices and PASID support allow creating "scalable IOV" devices, among other things. As these features are fundamental to a VM platform they need to be uniformly exposed to all the driver families that do DMA into VMs, which is currently VFIO and VDPA" For more background, see the extended explanations in Jason's pull request: https://lore.kernel.org/lkml/Y5dzTU8dlmXTbzoJ@nvidia.com/ * tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (62 commits) iommufd: Change the order of MSI setup iommufd: Improve a few unclear bits of code iommufd: Fix comment typos vfio: Move vfio group specific code into group.c vfio: Refactor dma APIs for emulated devices vfio: Wrap vfio group module init/clean code into helpers vfio: Refactor vfio_device open and close vfio: Make vfio_device_open() truly device specific vfio: Swap order of vfio_device_container_register() and open_device() vfio: Set device->group in helper function vfio: Create wrappers for group register/unregister vfio: Move the sanity check of the group to vfio_create_group() vfio: Simplify vfio_create_group() iommufd: Allow iommufd to supply /dev/vfio/vfio vfio: Make vfio_container optionally compiled vfio: Move container related MODULE_ALIAS statements into container.c vfio-iommufd: Support iommufd for emulated VFIO devices vfio-iommufd: Support iommufd for physical VFIO devices vfio-iommufd: Allow iommufd to be used in place of a container fd vfio: Use IOMMU_CAP_ENFORCE_CACHE_COHERENCY for vfio_file_enforced_coherent() ...
2022-12-02iommu/vt-d: Fix PCI device refcount leak in dmar_dev_scope_init()Xiongfeng Wang1-0/+1
for_each_pci_dev() is implemented by pci_get_device(). The comment of pci_get_device() says that it will increase the reference count for the returned pci_dev and also decrease the reference count for the input pci_dev @from if it is not NULL. If we break for_each_pci_dev() loop with pdev not NULL, we need to call pci_dev_put() to decrease the reference count. Add the missing pci_dev_put() for the error path to avoid reference count leak. Fixes: 2e4552893038 ("iommu/vt-d: Unify the way to process DMAR device scope array") Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Link: https://lore.kernel.org/r/20221121113649.190393-3-wangxiongfeng2@huawei.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2022-11-03iommu: Add max_pasids field in struct iommu_deviceLu Baolu1-0/+7
Use this field to keep the number of supported PASIDs that an IOMMU hardware is able to support. This is a generic attribute of an IOMMU and lifting it into the per-IOMMU device structure makes it possible to allocate a PASID for device without calls into the IOMMU drivers. Any iommu driver that supports PASID related features should set this field before enabling them on the devices. In the Intel IOMMU driver, intel_iommu_sm is moved to CONFIG_INTEL_IOMMU enclave so that the pasid_supported() helper could be used in dmar.c without compilation errors. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Yi Liu <yi.l.liu@intel.com> Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org> Tested-by: Tony Zhu <tony.zhu@intel.com> Link: https://lore.kernel.org/r/20221031005917.45690-2-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2022-09-21Revert "iommu/vt-d: Fix possible recursive locking in intel_iommu_init()"Lu Baolu1-7/+0
This reverts commit 9cd4f1434479f1ac25c440c421fbf52069079914. Some issues were reported on the original commit. Some thunderbolt devices don't work anymore due to the following DMA fault. DMAR: DRHD: handling fault status reg 2 DMAR: [INTR-REMAP] Request device [09:00.0] fault index 0x8080 [fault reason 0x25] Blocked a compatibility format interrupt request Bring it back for now to avoid functional regression. Fixes: 9cd4f1434479f ("iommu/vt-d: Fix possible recursive locking in intel_iommu_init()") Link: https://lore.kernel.org/linux-iommu/485A6EA5-6D58-42EA-B298-8571E97422DE@getmailspring.com/ Link: https://bugzilla.kernel.org/show_bug.cgi?id=216497 Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: <stable@vger.kernel.org> # 5.19.x Reported-and-tested-by: George Hilliard <thirtythreeforty@gmail.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20220920081701.3453504-1-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>