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2024-07-25Merge tag 'driver-core-6.11-rc1' of ↵Linus Torvalds2-4/+3
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the big set of driver core changes for 6.11-rc1. Lots of stuff in here, with not a huge diffstat, but apis are evolving which required lots of files to be touched. Highlights of the changes in here are: - platform remove callback api final fixups (Uwe took many releases to get here, finally!) - Rust bindings for basic firmware apis and initial driver-core interactions. It's not all that useful for a "write a whole driver in rust" type of thing, but the firmware bindings do help out the phy rust drivers, and the driver core bindings give a solid base on which others can start their work. There is still a long way to go here before we have a multitude of rust drivers being added, but it's a great first step. - driver core const api changes. This reached across all bus types, and there are some fix-ups for some not-common bus types that linux-next and 0-day testing shook out. This work is being done to help make the rust bindings more safe, as well as the C code, moving toward the end-goal of allowing us to put driver structures into read-only memory. We aren't there yet, but are getting closer. - minor devres cleanups and fixes found by code inspection - arch_topology minor changes - other minor driver core cleanups All of these have been in linux-next for a very long time with no reported problems" * tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits) ARM: sa1100: make match function take a const pointer sysfs/cpu: Make crash_hotplug attribute world-readable dio: Have dio_bus_match() callback take a const * zorro: make match function take a const pointer driver core: module: make module_[add|remove]_driver take a const * driver core: make driver_find_device() take a const * driver core: make driver_[create|remove]_file take a const * firmware_loader: fix soundness issue in `request_internal` firmware_loader: annotate doctests as `no_run` devres: Correct code style for functions that return a pointer type devres: Initialize an uninitialized struct member devres: Fix memory leakage caused by driver API devm_free_percpu() devres: Fix devm_krealloc() wasting memory driver core: platform: Switch to use kmemdup_array() driver core: have match() callback in struct bus_type take a const * MAINTAINERS: add Rust device abstractions to DRIVER CORE device: rust: improve safety comments MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER firmware: rust: improve safety comments ...
2024-07-24Merge tag 'dmaengine-6.11-rc1' of ↵Linus Torvalds2-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine Pull dmaengine updates from Vinod Koul: "New support: - New dmaengine_prep_peripheral_dma_vec() to support transfers using dma vectors and documentation and user in AXI dma - STMicro STM32 DMA3 support and new capabilities of cyclic dma Updates: - Yaml conversion for Freescale imx dma and qdma bindings, sprd sc9860 dma binding - Altera msgdma updates for descriptor management" * tag 'dmaengine-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (35 commits) dt-bindings: fsl-qdma: fix interrupts 'if' check logic dt-bindings: dma: sprd,sc9860-dma: convert to YAML dmaengine: fsl-dpaa2-qdma: add missing MODULE_DESCRIPTION() macro dmaengine: ti: add missing MODULE_DESCRIPTION() macros dmaengine: ti: cppi41: add missing MODULE_DESCRIPTION() macro dmaengine: virt-dma: add missing MODULE_DESCRIPTION() macro dmaengine: ti: k3-udma: Fix BCHAN count with UHC and HC channels dmaengine: sh: rz-dmac: Fix lockdep assert warning dmaengine: qcom: gpi: clean up the IRQ disable/enable in gpi_reset_chan() dmaengine: fsl-edma: change the memory access from local into remote mode in i.MX 8QM dmaengine: qcom: gpi: remove unused struct 'reg_info' dmaengine: moxart-dma: remove unused struct 'moxart_filter_data' dt-bindings: fsl-qdma: Convert to yaml format dmaengine: fsl-edma: remove redundant "idle" field from fsl_chan dmaengine: fsl-edma: request per-channel IRQ only when channel is allocated dmaengine: stm32-dma3: defer channel registration to specify channel name dmaengine: add channel device name to channel registration dmaengine: stm32-dma3: improve residue granularity dmaengine: stm32-dma3: add device_pause and device_resume ops dmaengine: stm32-dma3: add DMA_MEMCPY capability ...
2024-07-09Merge branch 'iommufd_pri' into iommufd for-nextJason Gunthorpe1-1/+1
Lu Baolu says: ==================== This series implements the functionality of delivering IO page faults to user space through the IOMMUFD framework. One feasible use case is the nested translation. Nested translation is a hardware feature that supports two-stage translation tables for IOMMU. The second-stage translation table is managed by the host VMM, while the first-stage translation table is owned by user space. This allows user space to control the IOMMU mappings for its devices. When an IO page fault occurs on the first-stage translation table, the IOMMU hardware can deliver the page fault to user space through the IOMMUFD framework. User space can then handle the page fault and respond to the device top-down through the IOMMUFD. This allows user space to implement its own IO page fault handling policies. User space application that is capable of handling IO page faults should allocate a fault object, and bind the fault object to any domain that it is willing to handle the fault generatd for them. On a successful return of fault object allocation, the user can retrieve and respond to page faults by reading or writing to the file descriptor (FD) returned. The iommu selftest framework has been updated to test the IO page fault delivery and response functionality. ==================== * iommufd_pri: iommufd/selftest: Add coverage for IOPF test iommufd/selftest: Add IOPF support for mock device iommufd: Associate fault object with iommufd_hw_pgtable iommufd: Fault-capable hwpt attach/detach/replace iommufd: Add iommufd fault object iommufd: Add fault and response message definitions iommu: Extend domain attach group with handle support iommu: Add attach handle to struct iopf_group iommu: Remove sva handle list iommu: Introduce domain attachment handle Link: https://lore.kernel.org/all/20240702063444.105814-1-baolu.lu@linux.intel.com Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2024-07-04iommu: Introduce domain attachment handleLu Baolu1-1/+1
Currently, when attaching a domain to a device or its PASID, domain is stored within the iommu group. It could be retrieved for use during the window between attachment and detachment. With new features introduced, there's a need to store more information than just a domain pointer. This information essentially represents the association between a domain and a device. For example, the SVA code already has a custom struct iommu_sva which represents a bond between sva domain and a PASID of a device. Looking forward, the IOMMUFD needs a place to store the iommufd_device pointer in the core, so that the device object ID could be quickly retrieved in the critical fault handling path. Introduce domain attachment handle that explicitly represents the attachment relationship between a domain and a device or its PASID. Co-developed-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20240702063444.105814-2-baolu.lu@linux.intel.com Signed-off-by: Will Deacon <will@kernel.org>
2024-07-03driver core: have match() callback in struct bus_type take a const *Greg Kroah-Hartman1-3/+3
In the match() callback, the struct device_driver * should not be changed, so change the function callback to be a const *. This is one step of many towards making the driver core safe to have struct device_driver in read-only memory. Because the match() callback is in all busses, all busses are modified to handle this properly. This does entail switching some container_of() calls to container_of_const() to properly handle the constant *. For some busses, like PCI and USB and HV, the const * is cast away in the match callback as those busses do want to modify those structures at this point in time (they have a local lock in the driver structure.) That will have to be changed in the future if they wish to have their struct device * in read-only-memory. Cc: Rafael J. Wysocki <rafael@kernel.org> Reviewed-by: Alex Elder <elder@kernel.org> Acked-by: Sumit Garg <sumit.garg@linaro.org> Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-20driver core: make [device_]driver_attach take a const *Greg Kroah-Hartman1-1/+0
Change device_driver_attach() and driver_attach() to take a const * to struct device driver as neither of them modify the structure at all. Also, for some odd reason, drivers/dma/idxd/compat.c had a duplicate external reference to device_driver_attach(), so remove that to fix up the build, it should never have had that there in the first place. Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Vinod Koul <vkoul@kernel.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Petr Tesarik <petr.tesarik.ext@huawei.com> Cc: Alexander Lobakin <aleksander.lobakin@intel.com> Cc: dmaengine@vger.kernel.org Link: https://lore.kernel.org/r/2024061401-rasping-manger-c385@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-11dmaengine: add channel device name to channel registrationAmelie Delaunay1-1/+1
Channel device name is used for sysfs, but also by dmatest filter function. With dynamic channel registration, channels can be registered after dma controller registration. Users may want to have specific channel names. If name is NULL, the channel name relies on previous implementation, dma<controller_device_id>chan<channel_device_id>. Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com> Link: https://lore.kernel.org/r/20240531150712.2503554-11-amelie.delaunay@foss.st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-06-11dmaengine: idxd: Fix possible Use-After-Free in irq_process_work_listLi RongQing1-1/+3
Use list_for_each_entry_safe() to allow iterating through the list and deleting the entry in the iteration process. The descriptor is freed via idxd_desc_complete() and there's a slight chance may cause issue for the list iterator when the descriptor is reused by another thread without it being deleted from the list. Fixes: 16e19e11228b ("dmaengine: idxd: Fix list corruption in description completion") Signed-off-by: Li RongQing <lirongqing@baidu.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Link: https://lore.kernel.org/r/20240603012444.11902-1-lirongqing@baidu.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-06-07dmaengine: add missing MODULE_DESCRIPTION() macrosJeff Johnson1-0/+1
make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dma/idxd/idxd.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dma/ti/omap-dma.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dma/dmatest.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/dma/ioat/ioatdma.o Add the missing invocations of the MODULE_DESCRIPTION() macro. Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Link: https://lore.kernel.org/r/20240606-md-drivers-dma-v2-1-0770dfdf74dd@quicinc.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-05-21Merge tag 'dmaengine-6.10-rc1' of ↵Linus Torvalds1-9/+9
git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine Pull dmaengine updates from Vinod Koul: "New HW support: - Freescale i.MX8ULP edma support in edma driver - StarFive JH8100 DMA support in Synopsis axi-dmac driver Updates: - Tracing support for freescale edma driver, updates to dpaa2 driver - Remove unused QCom hidma DT support - Support for i2c dma in imx-sdma - Maintainers update for idxd and edma drivers" * tag 'dmaengine-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (42 commits) MAINTAINERS: Update role for IDXD driver dmaengine: fsl-edma: use _Generic to handle difference type dmaengine: fsl-edma: add trace event support dmaengine: idxd: Avoid unnecessary destruction of file_ida dmaengine: xilinx: xdma: fix module autoloading dt-bindings: dma: fsl-edma: allow 'power-domains' property dt-bindings: dma: fsl-edma: remove 'clocks' from required dmaengine: fsl-dpaa2-qdma: Fix kernel-doc check warning dmaengine: imx-sdma: Add i2c dma support dmaengine: imx-sdma: utilize compiler to calculate ADDRS_ARRAY_SIZE_V<n> dt-bindings: fsl-imx-sdma: Add I2C peripheral types ID dt-bindings: fsl-dma: fsl-edma: clean up unused "fsl,imx8qm-adma" compatible string dmaengine: fsl-edma: clean up unused "fsl,imx8qm-adma" compatible string dt-bindings: dma: Drop unused QCom hidma binding dmaengine: qcom: Drop hidma DT support dmaengine: pl08x: Use kcalloc() instead of kzalloc() dmaengine: fsl-dpaa2-qdma: Update DPDMAI interfaces to version 3 dmaengine: fsl-edma: fix miss mutex unlock at an error return path dmaengine: pch_dma: remove unused function chan2parent dmaengine: fsl-dpaa2-qdma: Add dpdmai_cmd_open ...
2024-05-13dmaengine: idxd: add a write() method for applications to submit workNikhil Rao2-2/+90
After the patch to restrict the use of mmap() to CAP_SYS_RAWIO for the currently existing devices, most applications can no longer make use of the accelerators as in production "you don't run things as root". To keep the DSA and IAA accelerators usable, hook up a write() method so that applications can still submit work. In the write method, sufficient input validation is performed to avoid the security issue that required the mmap CAP_SYS_RAWIO check. One complication is that the DSA device allows for indirect ("batched") descriptors. There is no reasonable way to do the input validation on these indirect descriptors so the write() method will not allow these to be submitted to the hardware on affected hardware, and the sysfs enumeration of support for the opcode is also removed. Early performance data shows that the performance delta for most common cases is within the noise. Signed-off-by: Nikhil Rao <nikhil.rao@intel.com> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2024-05-13dmaengine: idxd: add a new security check to deal with a hardware erratumArjan van de Ven3-0/+19
On Sapphire Rapids and related platforms, the DSA and IAA devices have an erratum that causes direct access (for example, by using the ENQCMD or MOVDIR64 instructions) from untrusted applications to be a security problem. To solve this, add a flag to the PCI device enumeration and device structures to indicate the presence/absence of this security exposure. In the mmap() method of the device, this flag is then used to enforce that the user has the CAP_SYS_RAWIO capability. In a future patch, a write() based method will be added that allows untrusted applications submit work to the accelerator, where the kernel can do sanity checking on the user input to ensure secure operation of the accelerator. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2024-05-13VFIO: Add the SPR_DSA and SPR_IAX devices to the denylistArjan van de Ven1-3/+0
Due to an erratum with the SPR_DSA and SPR_IAX devices, it is not secure to assign these devices to virtual machines. Add the PCI IDs of these devices to the VFIO denylist to ensure that this is handled appropriately by the VFIO subsystem. The SPR_DSA and SPR_IAX devices are on-SOC devices for the Sapphire Rapids (and related) family of products that perform data movement and compression. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
2024-05-04dmaengine: idxd: Avoid unnecessary destruction of file_idaFenghua Yu1-1/+0
file_ida is allocated during cdev open and is freed accordingly during cdev release. This sequence is guaranteed by driver file operations. Therefore, there is no need to destroy an already empty file_ida when the WQ cdev is removed. Worse, ida_free() in cdev release may happen after destruction of file_ida per WQ cdev. This can lead to accessing an id in file_ida after it has been destroyed, resulting in a kernel panic. Remove ida_destroy(&file_ida) to address these issues. Fixes: e6fd6d7e5f0f ("dmaengine: idxd: add a device to represent the file opened") Signed-off-by: Lijun Pan <lijun.pan@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240130013954.2024231-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-04-07dmaengine: idxd: Fix oops during rmmod on single-CPU platformsFenghua Yu1-6/+3
During the removal of the idxd driver, registered offline callback is invoked as part of the clean up process. However, on systems with only one CPU online, no valid target is available to migrate the perf context, resulting in a kernel oops: BUG: unable to handle page fault for address: 000000000002a2b8 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 1470e1067 P4D 0 Oops: 0002 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 20 Comm: cpuhp/0 Not tainted 6.8.0-rc6-dsa+ #57 Hardware name: Intel Corporation AvenueCity/AvenueCity, BIOS BHSDCRB1.86B.2492.D03.2307181620 07/18/2023 RIP: 0010:mutex_lock+0x2e/0x50 ... Call Trace: <TASK> __die+0x24/0x70 page_fault_oops+0x82/0x160 do_user_addr_fault+0x65/0x6b0 __pfx___rdmsr_safe_on_cpu+0x10/0x10 exc_page_fault+0x7d/0x170 asm_exc_page_fault+0x26/0x30 mutex_lock+0x2e/0x50 mutex_lock+0x1e/0x50 perf_pmu_migrate_context+0x87/0x1f0 perf_event_cpu_offline+0x76/0x90 [idxd] cpuhp_invoke_callback+0xa2/0x4f0 __pfx_perf_event_cpu_offline+0x10/0x10 [idxd] cpuhp_thread_fun+0x98/0x150 smpboot_thread_fn+0x27/0x260 smpboot_thread_fn+0x1af/0x260 __pfx_smpboot_thread_fn+0x10/0x10 kthread+0x103/0x140 __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x50 __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 <TASK> Fix the issue by preventing the migration of the perf context to an invalid target. Fixes: 81dd4d4d6178 ("dmaengine: idxd: Add IDXD performance monitor support") Reported-by: Terrence Xu <terrence.xu@intel.com> Tested-by: Terrence Xu <terrence.xu@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: https://lore.kernel.org/r/20240313214031.1658045-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-04-07dmaengine: idxd: Convert spinlock to mutex to lock evl workqueueRex Zhang6-13/+12
drain_workqueue() cannot be called safely in a spinlocked context due to possible task rescheduling. In the multi-task scenario, calling queue_work() while drain_workqueue() will lead to a Call Trace as pushing a work on a draining workqueue is not permitted in spinlocked context. Call Trace: <TASK> ? __warn+0x7d/0x140 ? __queue_work+0x2b2/0x440 ? report_bug+0x1f8/0x200 ? handle_bug+0x3c/0x70 ? exc_invalid_op+0x18/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? __queue_work+0x2b2/0x440 queue_work_on+0x28/0x30 idxd_misc_thread+0x303/0x5a0 [idxd] ? __schedule+0x369/0xb40 ? __pfx_irq_thread_fn+0x10/0x10 ? irq_thread+0xbc/0x1b0 irq_thread_fn+0x21/0x70 irq_thread+0x102/0x1b0 ? preempt_count_add+0x74/0xa0 ? __pfx_irq_thread_dtor+0x10/0x10 ? __pfx_irq_thread+0x10/0x10 kthread+0x103/0x140 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> The current implementation uses a spinlock to protect event log workqueue and will lead to the Call Trace due to potential task rescheduling. To address the locking issue, convert the spinlock to mutex, allowing the drain_workqueue() to be called in a safe mutex-locked context. This change ensures proper synchronization when accessing the event log workqueue, preventing potential Call Trace and improving the overall robustness of the code. Fixes: c40bd7d9737b ("dmaengine: idxd: process user page faults for completion record") Signed-off-by: Rex Zhang <rex.zhang@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Lijun Pan <lijun.pan@intel.com> Link: https://lore.kernel.org/r/20240404223949.2885604-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-04-07dmaengine: idxd: Check for driver name match before sva user featureJerry Snitselaar1-8/+9
Currently if the user driver is probed on a workqueue configured for another driver with SVA not enabled on the system, it will print out a number of probe failing messages like the following: [ 264.831140] user: probe of wq13.0 failed with error -95 On some systems, such as GNR, the number of messages can reach over 100. Move the SVA feature check to be after the driver name match check. Cc: Vinod Koul <vkoul@kernel.org> Cc: dmaengine@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com> Link: https://lore.kernel.org/r/20240405213941.3629709-1-jsnitsel@redhat.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-03-15Merge tag 'dmaengine-6.9-rc1' of ↵Linus Torvalds4-15/+15
git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine Pull dmaengine updates from Vinod Koul: "New hardware support: - Allwinner H616 dma support - Renesas r8a779h0 dma controller support - TI CSI2RX dma support Updates: - Freescale edma driver updates for TCD64csupport for i.MX95 - constify of pointers and args - Yaml conversion for MediaTek High-Speed controller binding - TI k3 udma support for TX/RX DMA channels for thread IDs: * tag 'dmaengine-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (25 commits) dmaengine: of: constify of_phandle_args in of_dma_find_controller() dmaengine: pl08x: constify pointer to char in filter function MAINTAINERS: change in AMD ptdma maintainer MAINTAINERS: adjust file entry in MEDIATEK DMA DRIVER dmaengine: idxd: constify the struct device_type usage dt-bindings: renesas,rcar-dmac: Add r8a779h0 support dt-bindings: dma: convert MediaTek High-Speed controller to the json-schema dmaengine: idxd: make dsa_bus_type const dmaengine: fsl-edma: integrate TCD64 support for i.MX95 dt-bindings: fsl-dma: fsl-edma: add fsl,imx95-edma5 compatible string dmaengine: mcf-edma: utilize edma_write_tcdreg() macro for TCD Access dmaengine: fsl-edma: add address for channel mux register in fsl_edma_chan dmaengine: fsl-edma: fix spare build warning dmaengine: fsl-edma: involve help macro fsl_edma_set(get)_tcd() dt-bindings: mmp-dma: convert to YAML dmaengine: ti: k3-psil-j721s2: Add entry for CSI2RX dmaengine: ti: k3-udma-glue: Add function to request RX chan for thread ID dmaengine: ti: k3-udma-glue: Add function to request TX chan for thread ID dmaengine: ti: k3-udma-glue: Update name for remote RX channel device dmaengine: ti: k3-udma-glue: Add function to parse channel by ID ...
2024-02-22dmaengine: idxd: constify the struct device_type usageRicardo B. Marliere3-13/+13
Since commit aed65af1cc2f ("drivers: make device_type const"), the driver core can properly handle constant struct device_type. Move the dsa_device_type, iax_device_type, idxd_wq_device_type, idxd_cdev_file_type, idxd_cdev_device_type and idxd_group_device_type variables to be constant structures as well, placing it into read-only memory which can not be modified at runtime. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: "Ricardo B. Marliere" <ricardo@marliere.net> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Link: https://lore.kernel.org/r/20240219-device_cleanup-dmaengine-v1-1-9f72f3cf3587@marliere.net Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-02-22dmaengine: idxd: Ensure safe user copy of completion recordFenghua Yu1-3/+12
If CONFIG_HARDENED_USERCOPY is enabled, copying completion record from event log cache to user triggers a kernel bug. [ 1987.159822] usercopy: Kernel memory exposure attempt detected from SLUB object 'dsa0' (offset 74, size 31)! [ 1987.170845] ------------[ cut here ]------------ [ 1987.176086] kernel BUG at mm/usercopy.c:102! [ 1987.180946] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 1987.186866] CPU: 17 PID: 528 Comm: kworker/17:1 Not tainted 6.8.0-rc2+ #5 [ 1987.194537] Hardware name: Intel Corporation AvenueCity/AvenueCity, BIOS BHSDCRB1.86B.2492.D03.2307181620 07/18/2023 [ 1987.206405] Workqueue: wq0.0 idxd_evl_fault_work [idxd] [ 1987.212338] RIP: 0010:usercopy_abort+0x72/0x90 [ 1987.217381] Code: 58 65 9c 50 48 c7 c2 17 85 61 9c 57 48 c7 c7 98 fd 6b 9c 48 0f 44 d6 48 c7 c6 b3 08 62 9c 4c 89 d1 49 0f 44 f3 e8 1e 2e d5 ff <0f> 0b 49 c7 c1 9e 42 61 9c 4c 89 cf 4d 89 c8 eb a9 66 66 2e 0f 1f [ 1987.238505] RSP: 0018:ff62f5cf20607d60 EFLAGS: 00010246 [ 1987.244423] RAX: 000000000000005f RBX: 000000000000001f RCX: 0000000000000000 [ 1987.252480] RDX: 0000000000000000 RSI: ffffffff9c61429e RDI: 00000000ffffffff [ 1987.260538] RBP: ff62f5cf20607d78 R08: ff2a6a89ef3fffe8 R09: 00000000fffeffff [ 1987.268595] R10: ff2a6a89eed00000 R11: 0000000000000003 R12: ff2a66934849c89a [ 1987.276652] R13: 0000000000000001 R14: ff2a66934849c8b9 R15: ff2a66934849c899 [ 1987.284710] FS: 0000000000000000(0000) GS:ff2a66b22fe40000(0000) knlGS:0000000000000000 [ 1987.293850] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1987.300355] CR2: 00007fe291a37000 CR3: 000000010fbd4005 CR4: 0000000000f71ef0 [ 1987.308413] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1987.316470] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 [ 1987.324527] PKRU: 55555554 [ 1987.327622] Call Trace: [ 1987.330424] <TASK> [ 1987.332826] ? show_regs+0x6e/0x80 [ 1987.336703] ? die+0x3c/0xa0 [ 1987.339988] ? do_trap+0xd4/0xf0 [ 1987.343662] ? do_error_trap+0x75/0xa0 [ 1987.347922] ? usercopy_abort+0x72/0x90 [ 1987.352277] ? exc_invalid_op+0x57/0x80 [ 1987.356634] ? usercopy_abort+0x72/0x90 [ 1987.360988] ? asm_exc_invalid_op+0x1f/0x30 [ 1987.365734] ? usercopy_abort+0x72/0x90 [ 1987.370088] __check_heap_object+0xb7/0xd0 [ 1987.374739] __check_object_size+0x175/0x2d0 [ 1987.379588] idxd_copy_cr+0xa9/0x130 [idxd] [ 1987.384341] idxd_evl_fault_work+0x127/0x390 [idxd] [ 1987.389878] process_one_work+0x13e/0x300 [ 1987.394435] ? __pfx_worker_thread+0x10/0x10 [ 1987.399284] worker_thread+0x2f7/0x420 [ 1987.403544] ? _raw_spin_unlock_irqrestore+0x2b/0x50 [ 1987.409171] ? __pfx_worker_thread+0x10/0x10 [ 1987.414019] kthread+0x107/0x140 [ 1987.417693] ? __pfx_kthread+0x10/0x10 [ 1987.421954] ret_from_fork+0x3d/0x60 [ 1987.426019] ? __pfx_kthread+0x10/0x10 [ 1987.430281] ret_from_fork_asm+0x1b/0x30 [ 1987.434744] </TASK> The issue arises because event log cache is created using kmem_cache_create() which is not suitable for user copy. Fix the issue by creating event log cache with kmem_cache_create_usercopy(), ensuring safe user copy. Fixes: c2f156bf168f ("dmaengine: idxd: create kmem cache for event log fault items") Reported-by: Tony Zhu <tony.zhu@intel.com> Tested-by: Tony Zhu <tony.zhu@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Lijun Pan <lijun.pan@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240209191412.1050270-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-02-16dmaengine: idxd: make dsa_bus_type constRicardo B. Marliere2-2/+2
Since commit d492cc2573a0 ("driver core: device.h: make struct bus_type a const *"), the driver core can properly handle constant struct bus_type, move the dsa_bus_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: "Ricardo B. Marliere" <ricardo@marliere.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20240213-bus_cleanup-idxd-v1-1-c3e703675387@marliere.net Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-02-16dmaengine: idxd: Remove shadow Event Log head stored in idxdFenghua Yu4-5/+3
head is defined in idxd->evl as a shadow of head in the EVLSTATUS register. There are two issues related to the shadow head: 1. Mismatch between the shadow head and the state of the EVLSTATUS register: If Event Log is supported, upon completion of the Enable Device command, the Event Log head in the variable idxd->evl->head should be cleared to match the state of the EVLSTATUS register. But the variable is not reset currently, leading mismatch between the variable and the register state. The mismatch causes incorrect processing of Event Log entries. 2. Unnecessary shadow head definition: The shadow head is unnecessary as head can be read directly from the EVLSTATUS register. Reading head from the register incurs no additional cost because event log head and tail are always read together and tail is already read directly from the register as required by hardware. Remove the shadow Event Log head stored in idxd->evl to address the mentioned issues. Fixes: 244da66cda35 ("dmaengine: idxd: setup event log configuration") Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240215024931.1739621-1-fenghua.yu@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2024-01-20Merge tag 'dmaengine-fix-6.8-rc1' of ↵Linus Torvalds2-3/+10
git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine Pull dmaengine updates from Vinod Koul: "New support: - Loongson LS2X APB DMA controller - sf-pdma: mpfs-pdma support - Qualcomm X1E80100 GPI dma controller support Updates: - Xilinx XDMA updates to support interleaved DMA transfers - TI PSIL threads for AM62P and J722S and cfg register regions description - axi-dmac Improving the cyclic DMA transfers - Tegra Support dma-channel-mask property - Remaining platform remove callback returning void conversions Driver fixes for: - Xilinx xdma driver operator precedence and initialization fix - Excess kernel-doc warning fix in imx-sdma xilinx xdma drivers - format-overflow warning fix for rz-dmac, sh usb dmac drivers - 'output may be truncated' fix for shdma, fsl-qdma and dw-edma drivers" * tag 'dmaengine-fix-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (58 commits) dmaengine: dw-edma: increase size of 'name' in debugfs code dmaengine: fsl-qdma: increase size of 'irq_name' dmaengine: shdma: increase size of 'dev_id' dmaengine: xilinx: xdma: Fix kernel-doc warnings dmaengine: usb-dmac: Avoid format-overflow warning dmaengine: sh: rz-dmac: Avoid format-overflow warning dmaengine: imx-sdma: fix Excess kernel-doc warnings dmaengine: xilinx: xdma: Fix initialization location of desc in xdma_channel_isr() dmaengine: xilinx: xdma: Fix operator precedence in xdma_prep_interleaved_dma() dmaengine: xilinx: xdma: statify xdma_prep_interleaved_dma dmaengine: xilinx: xdma: Workaround truncation compilation error dmaengine: pl330: issue_pending waits until WFP state dmaengine: xilinx: xdma: Implement interleaved DMA transfers dmaengine: xilinx: xdma: Prepare the introduction of interleaved DMA transfers dmaengine: xilinx: xdma: Add transfer error reporting dmaengine: xilinx: xdma: Add error checking in xdma_channel_isr() dmaengine: xilinx: xdma: Rework xdma_terminate_all() dmaengine: xilinx: xdma: Ease dma_pool alignment requirements dmaengine: xilinx: xdma: Add necessary macro definitions dmaengine: xilinx: xdma: Get rid of unused code ...
2024-01-19Merge tag 'dmaengine-6.8-rc1' into fixesVinod Koul2-3/+10
dmaengine updates for v6.8 New support: - Loongson LS2X APB DMA controller - sf-pdma: mpfs-pdma support - Qualcomm X1E80100 GPI dma controller support Updates: - Xilinx XDMA updates to support interleaved DMA transfers - TI PSIL threads for AM62P and J722S and cfg register regions description - axi-dmac Improving the cyclic DMA transfers - Tegra Support dma-channel-mask property - Remaining platform remove callback returning void conversions
2024-01-10Merge tag 'v6.8-p1' of ↵Linus Torvalds10-31/+169
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "API: - Add incremental lskcipher/skcipher processing Algorithms: - Remove SHA1 from drbg - Remove CFB and OFB Drivers: - Add comp high perf mode configuration in hisilicon/zip - Add support for 420xx devices in qat - Add IAA Compression Accelerator driver" * tag 'v6.8-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (172 commits) crypto: iaa - Account for cpu-less numa nodes crypto: scomp - fix req->dst buffer overflow crypto: sahara - add support for crypto_engine crypto: sahara - remove error message for bad aes request size crypto: sahara - remove unnecessary NULL assignments crypto: sahara - remove 'active' flag from sahara_aes_reqctx struct crypto: sahara - use dev_err_probe() crypto: sahara - use devm_clk_get_enabled() crypto: sahara - use BIT() macro crypto: sahara - clean up macro indentation crypto: sahara - do not resize req->src when doing hash operations crypto: sahara - fix processing hash requests with req->nbytes < sg->length crypto: sahara - improve error handling in sahara_sha_process() crypto: sahara - fix wait_for_completion_timeout() error handling crypto: sahara - fix ahash reqsize crypto: sahara - handle zero-length aes requests crypto: skcipher - remove excess kerneldoc members crypto: shash - remove excess kerneldoc members crypto: qat - generate dynamically arbiter mappings crypto: qat - add support for ring pair level telemetry ...
2023-12-21dmaengine: idxd: Move dma_free_coherent() out of spinlocked contextRex Zhang1-1/+8
Task may be rescheduled within dma_free_coherent(). So dma_free_coherent() can't be called between spin_lock() and spin_unlock() to avoid Call Trace: Call Trace: <TASK> dump_stack_lvl+0x37/0x50 __might_resched+0x16a/0x1c0 vunmap+0x2c/0x70 __iommu_dma_free+0x96/0x100 idxd_device_evl_free+0xd5/0x100 [idxd] device_release_driver_internal+0x197/0x200 unbind_store+0xa1/0xb0 kernfs_fop_write_iter+0x120/0x1c0 vfs_write+0x2d3/0x400 ksys_write+0x63/0xe0 do_syscall_64+0x44/0xa0 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 Move it out of the context. Fixes: 244da66cda35 ("dmaengine: idxd: setup event log configuration") Signed-off-by: Rex Zhang <rex.zhang@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Link: https://lore.kernel.org/r/20231212022158.358619-2-rex.zhang@intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-12-21dmaengine: idxd: Remove usage of the deprecated ida_simple_xx() APIChristophe JAILLET1-2/+2
ida_alloc() and ida_free() should be preferred to the deprecated ida_simple_get() and ida_simple_remove(). This is less verbose. Note that the upper limit of ida_simple_get() is exclusive, but the one of ida_alloc_range() is inclusive. Sothis change allows one more device. MINORMASK is ((1U << MINORBITS) - 1), so allowing MINORMASK as a maximum value makes sense. It is also consistent with other "ida_.*MINORMASK" and "ida_*MINOR()" usages. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Lijun Pan <lijun.pan@intel.com> Link: https://lore.kernel.org/r/ac991f5f42112fa782a881d391d447529cbc4a23.1702967302.git.christophe.jaillet@wanadoo.fr Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-12-15dmaengine: idxd: Add support for device/wq defaultsTom Zanussi4-1/+65
Add a load_device_defaults() function pointer to struct idxd_driver_data, which if defined, will be called when an idxd device is probed and will allow the idxd device to be configured with default values. The load_device_defaults() function is passed an idxd device to work with to set specific device attributes. Also add a load_device_defaults() implementation IAA devices; future patches would add default functions for other device types such as DSA. The way idxd device probing works, if the device configuration is valid at that point e.g. at least one workqueue and engine is properly configured then the device will be enabled and ready to go. The IAA implementation, idxd_load_iaa_device_defaults(), configures a single workqueue (wq0) for each device with the following default values: mode "dedicated" threshold 0 size Total WQ Size from WQCAP priority 10 type IDXD_WQT_KERNEL group 0 name "iaa_crypto" driver_name "crypto" Note that this now adds another configuration step for any users that want to configure their own devices/workqueus with something different in that they'll first need to disable (in the case of IAA) wq0 and the device itself before they can set their own attributes and re-enable, since they've been already been auto-enabled. Note also that in order for the new configuration to be applied to the deflate-iaa crypto algorithm the iaa_crypto module needs to unregister the old version, which is accomplished by removing the iaa_crypto module, and re-registering it with the new configuration by reinserting the iaa_crypto module. Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-12-15dmaengine: idxd: add callback support for iaa cryptoTom Zanussi5-20/+65
Create a lightweight callback interface to allow idxd sub-drivers to be notified when work sent to idxd wqs has completed. For a sub-driver to be notified of work completion, it needs to: - Set the descriptor's 'Request Completion Interrupt' (IDXD_OP_FLAG_RCI) - Set the sub-driver desc_complete() callback when registering the sub-driver e.g.: struct idxd_device_driver my_drv = { .probe = my_probe, .desc_complete = my_complete, } - Set the sub-driver-specific context in the sub-driver's descriptor e.g: idxd_desc->crypto.req = req; idxd_desc->crypto.tfm = tfm; idxd_desc->crypto.src_addr = src_addr; idxd_desc->crypto.dst_addr = dst_addr; When the work completes and the completion irq fires, idxd will invoke the desc_complete() callback with pointers to the descriptor, context, and completion_type. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-12-15dmaengine: idxd: Add wq private data accessorsTom Zanussi1-0/+10
Add the accessors idxd_wq_set_private() and idxd_wq_get_private() allowing users to set and retrieve a private void * associated with an idxd_wq. The private data is stored in the idxd_dev.conf_dev associated with each idxd_wq. Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-12-15dmaengine: idxd: Export wq resource management functionsTom Zanussi1-0/+5
To allow idxd sub-drivers to access the wq resource management functions, export them. Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-12-15dmaengine: idxd: Export descriptor management functionsTom Zanussi1-0/+3
To allow idxd sub-drivers to access the descriptor management functions, export them. Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-12-15dmaengine: idxd: Rename drv_enable/disable_wq to idxd_drv_enable/disable_wq, ↵Tom Zanussi4-10/+12
and export Rename drv_enable_wq and drv_disable_wq to idxd_drv_enable_wq and idxd_drv_disable_wq respectively, so that they're no longer too generic to be exported. This also matches existing naming within the idxd driver. And to allow idxd sub-drivers to enable and disable wqs, export them. Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-12-15dmaengine: idxd: add external module driver support for dsa_bus_typeDave Jiang2-0/+9
Add support to allow an external driver to be registered to the dsa_bus_type and also auto-loaded. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-12-11dmaengine: idxd: Fix incorrect descriptions for GRPCFG registerGuanjun1-5/+7
Fix incorrect descriptions for the GRPCFG register which has three sub-registers (GRPWQCFG, GRPENGCFG and GRPFLGCFG). No functional changes Signed-off-by: Guanjun <guanjun@linux.alibaba.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Lijun Pan <lijun.pan@intel.com> Link: https://lore.kernel.org/r/20231211053704.2725417-3-guanjun@linux.alibaba.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-12-11dmaengine: idxd: Protect int_handle field in hw descriptorGuanjun1-7/+7
The int_handle field in hw descriptor should also be protected by wmb() before possibly triggering a DMA read. Fixes: eb0cf33a91b4 (dmaengine: idxd: move interrupt handle assignment) Signed-off-by: Guanjun <guanjun@linux.alibaba.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fenghua Yu <fenghua.yu@intel.com> Reviewed-by: Lijun Pan <lijun.pan@intel.com> Link: https://lore.kernel.org/r/20231211053704.2725417-2-guanjun@linux.alibaba.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2023-11-03Merge tag 'dmaengine-6.7-rc1' of ↵Linus Torvalds6-5/+61
git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine Pull dmaengine updates from Vinod Koul: - Big pile of __counted_by attribute annotations to several structures for bounds checking of flexible arrays at run-time - Another big pile platform remove callback returning void changes - Device tree device_get_match_data() usage and dropping of_match_device() calls - Minor driver updates to pxa, idxd fsl, hisi etc drivers * tag 'dmaengine-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (106 commits) dmaengine: stm32-mdma: correct desc prep when channel running dmaengine: dw-axi-dmac: Add support DMAX_NUM_CHANNELS > 16 dmaengine: xilinx: xilinx_dma: Fix kernel doc about xilinx_dma_remove() dmaengine: mmp_tdma: drop unused variable 'of_id' MAINTAINERS: Add entries for NXP(Freescale) eDMA drivers dmaengine: xilinx: xdma: Support cyclic transfers dmaengine: xilinx: xdma: Prepare the introduction of cyclic transfers dmaengine: Drop unnecessary of_match_device() calls dmaengine: Use device_get_match_data() dmaengine: pxa_dma: Annotate struct pxad_desc_sw with __counted_by dmaengine: pxa_dma: Remove an erroneous BUG_ON() in pxad_free_desc() dmaengine: xilinx: xdma: Use resource_size() in xdma_probe() dmaengine: fsl-dpaa2-qdma: Remove redundant initialization owner in dpaa2_qdma_driver dmaengine: Remove unused declaration dma_chan_cleanup() dmaengine: mmp: fix Wvoid-pointer-to-enum-cast warning dmaengine: qcom: fix Wvoid-pointer-to-enum-cast warning dmaengine: fsl-edma: Remove redundant dev_err() for platform_get_irq() dmaengine: ep93xx_dma: Annotate struct ep93xx_dma_engine with __counted_by dmaengine: idxd: add wq driver name support for accel-config user tool dmaengine: fsl-edma: Annotate struct struct fsl_edma_engine with __counted_by ...
2023-10-04dmaengine: idxd: use spin_lock_irqsave before wait_event_lock_irqRex Zhang1-2/+3
In idxd_cmd_exec(), wait_event_lock_irq() explicitly calls spin_unlock_irq()/spin_lock_irq(). If the interrupt is on before entering wait_event_lock_irq(), it will become off status after wait_event_lock_irq() is called. Later, wait_for_completion() may go to sleep but irq is disabled. The scenario is warned in might_sleep(