From 7937a1bf32e31f80032c71511cc24d707753d07d Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Wed, 27 Nov 2024 19:51:59 -0800 Subject: [PATCH 1/4] iommufd: Fix typos in kernel-doc comments Fix typos/spellos in kernel-doc comments for readability. Fixes: aad37e71d5c4 ("iommufd: IOCTLs for the io_pagetable") Fixes: b7a0855eb95f ("iommu: Add new flag to explictly request PASID capable domain") Fixes: d68beb276ba2 ("iommu/arm-smmu-v3: Support IOMMU_HWPT_INVALIDATE using a VIOMMU object") Link: https://patch.msgid.link/r/20241128035159.374624-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap Acked-by: Nicolin Chen Signed-off-by: Jason Gunthorpe --- include/uapi/linux/iommufd.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index 059b6537f2b7..d7ce322fb93a 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -297,7 +297,7 @@ struct iommu_ioas_unmap { * ioctl(IOMMU_OPTION_HUGE_PAGES) * @IOMMU_OPTION_RLIMIT_MODE: * Change how RLIMIT_MEMLOCK accounting works. The caller must have privilege - * to invoke this. Value 0 (default) is user based accouting, 1 uses process + * to invoke this. Value 0 (default) is user based accounting, 1 uses process * based accounting. Global option, object_id must be 0 * @IOMMU_OPTION_HUGE_PAGES: * Value 1 (default) allows contiguous pages to be combined when generating @@ -390,7 +390,7 @@ struct iommu_vfio_ioas { * @IOMMU_HWPT_ALLOC_PASID: Requests a domain that can be used with PASID. The * domain can be attached to any PASID on the device. * Any domain attached to the non-PASID part of the - * device must also be flaged, otherwise attaching a + * device must also be flagged, otherwise attaching a * PASID will blocked. * If IOMMU does not support PASID it will return * error (-EOPNOTSUPP). @@ -766,7 +766,7 @@ struct iommu_hwpt_vtd_s1_invalidate { }; /** - * struct iommu_viommu_arm_smmuv3_invalidate - ARM SMMUv3 cahce invalidation + * struct iommu_viommu_arm_smmuv3_invalidate - ARM SMMUv3 cache invalidation * (IOMMU_VIOMMU_INVALIDATE_DATA_ARM_SMMUV3) * @cmd: 128-bit cache invalidation command that runs in SMMU CMDQ. * Must be little-endian. From af7f4780514f850322b2959032ecaa96e4b26472 Mon Sep 17 00:00:00 2001 From: Nicolin Chen Date: Tue, 3 Dec 2024 00:02:54 -0800 Subject: [PATCH 2/4] iommufd: Fix out_fput in iommufd_fault_alloc() As fput() calls the file->f_op->release op, where fault obj and ictx are getting released, there is no need to release these two after fput() one more time, which would result in imbalanced refcounts: refcount_t: decrement hit 0; leaking memory. WARNING: CPU: 48 PID: 2369 at lib/refcount.c:31 refcount_warn_saturate+0x60/0x230 Call trace: refcount_warn_saturate+0x60/0x230 (P) refcount_warn_saturate+0x60/0x230 (L) iommufd_fault_fops_release+0x9c/0xe0 [iommufd] ... VFS: Close: file count is 0 (f_op=iommufd_fops [iommufd]) WARNING: CPU: 48 PID: 2369 at fs/open.c:1507 filp_flush+0x3c/0xf0 Call trace: filp_flush+0x3c/0xf0 (P) filp_flush+0x3c/0xf0 (L) __arm64_sys_close+0x34/0x98 ... imbalanced put on file reference count WARNING: CPU: 48 PID: 2369 at fs/file.c:74 __file_ref_put+0x100/0x138 Call trace: __file_ref_put+0x100/0x138 (P) __file_ref_put+0x100/0x138 (L) __fput_sync+0x4c/0xd0 Drop those two lines to fix the warnings above. Cc: stable@vger.kernel.org Fixes: 07838f7fd529 ("iommufd: Add iommufd fault object") Link: https://patch.msgid.link/r/b5651beb3a6b1adeef26fffac24607353bf67ba1.1733212723.git.nicolinc@nvidia.com Signed-off-by: Nicolin Chen Reviewed-by: Yi Liu Signed-off-by: Jason Gunthorpe --- drivers/iommu/iommufd/fault.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/iommu/iommufd/fault.c b/drivers/iommu/iommufd/fault.c index 053b0e30f55a..1fe804e28a86 100644 --- a/drivers/iommu/iommufd/fault.c +++ b/drivers/iommu/iommufd/fault.c @@ -420,8 +420,6 @@ int iommufd_fault_alloc(struct iommufd_ucmd *ucmd) put_unused_fd(fdno); out_fput: fput(filep); - refcount_dec(&fault->obj.users); - iommufd_ctx_put(fault->ictx); out_abort: iommufd_object_abort_and_destroy(ucmd->ictx, &fault->obj); From a8c9df25f90e5155b70f5e2474c7299841e3335a Mon Sep 17 00:00:00 2001 From: Nicolin Chen Date: Tue, 3 Dec 2024 00:02:55 -0800 Subject: [PATCH 3/4] iommufd/selftest: Cover IOMMU_FAULT_QUEUE_ALLOC in iommufd_fail_nth This was missing in the series introducing the fault object. Thus, add it. Link: https://patch.msgid.link/r/d61b9b7f73276cc8f1aef9602bd35c486917506e.1733212723.git.nicolinc@nvidia.com Signed-off-by: Nicolin Chen Signed-off-by: Jason Gunthorpe --- tools/testing/selftests/iommu/iommufd_fail_nth.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/tools/testing/selftests/iommu/iommufd_fail_nth.c b/tools/testing/selftests/iommu/iommufd_fail_nth.c index 22f6fd5f0f74..64b1f8e1b0cf 100644 --- a/tools/testing/selftests/iommu/iommufd_fail_nth.c +++ b/tools/testing/selftests/iommu/iommufd_fail_nth.c @@ -615,7 +615,12 @@ TEST_FAIL_NTH(basic_fail_nth, access_pin_domain) /* device.c */ TEST_FAIL_NTH(basic_fail_nth, device) { + struct iommu_hwpt_selftest data = { + .iotlb = IOMMU_TEST_IOTLB_DEFAULT, + }; struct iommu_test_hw_info info; + uint32_t fault_id, fault_fd; + uint32_t fault_hwpt_id; uint32_t ioas_id; uint32_t ioas_id2; uint32_t stdev_id; @@ -678,6 +683,15 @@ TEST_FAIL_NTH(basic_fail_nth, device) if (_test_cmd_vdevice_alloc(self->fd, viommu_id, idev_id, 0, &vdev_id)) return -1; + if (_test_ioctl_fault_alloc(self->fd, &fault_id, &fault_fd)) + return -1; + close(fault_fd); + + if (_test_cmd_hwpt_alloc(self->fd, idev_id, hwpt_id, fault_id, + IOMMU_HWPT_FAULT_ID_VALID, &fault_hwpt_id, + IOMMU_HWPT_DATA_SELFTEST, &data, sizeof(data))) + return -1; + return 0; } From 2ca704f55e22b7b00cc7025953091af3c82fa5c0 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Tue, 12 Nov 2024 14:51:36 -0400 Subject: [PATCH 4/4] iommu/arm-smmu-v3: Improve uAPI comment for IOMMU_HW_INFO_TYPE_ARM_SMMUV3 Be specific about what fields should be accessed in the idr result and give other guidance to the VMM on how it should generate the vIDR. Discussion on the list, and review of the qemu implementation understood this needs to be clearer and more detailed. Link: https://patch.msgid.link/r/0-v1-191e5e24cec3+3b0-iommufd_smmuv3_hwinf_jgg@nvidia.com Reviewed-by: Kevin Tian Signed-off-by: Jason Gunthorpe --- include/uapi/linux/iommufd.h | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index d7ce322fb93a..34810f6ae2b5 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -558,16 +558,25 @@ struct iommu_hw_info_vtd { * For the details of @idr, @iidr and @aidr, please refer to the chapters * from 6.3.1 to 6.3.6 in the SMMUv3 Spec. * - * User space should read the underlying ARM SMMUv3 hardware information for - * the list of supported features. + * This reports the raw HW capability, and not all bits are meaningful to be + * read by userspace. Only the following fields should be used: * - * Note that these values reflect the raw HW capability, without any insight if - * any required kernel driver support is present. Bits may be set indicating the - * HW has functionality that is lacking kernel software support, such as BTM. If - * a VMM is using this information to construct emulated copies of these - * registers it should only forward bits that it knows it can support. + * idr[0]: ST_LEVEL, TERM_MODEL, STALL_MODEL, TTENDIAN , CD2L, ASID16, TTF + * idr[1]: SIDSIZE, SSIDSIZE + * idr[3]: BBML, RIL + * idr[5]: VAX, GRAN64K, GRAN16K, GRAN4K * - * In future, presence of required kernel support will be indicated in flags. + * - S1P should be assumed to be true if a NESTED HWPT can be created + * - VFIO/iommufd only support platforms with COHACC, it should be assumed to be + * true. + * - ATS is a per-device property. If the VMM describes any devices as ATS + * capable in ACPI/DT it should set the corresponding idr. + * + * This list may expand in future (eg E0PD, AIE, PBHA, D128, DS etc). It is + * important that VMMs do not read bits outside the list to allow for + * compatibility with future kernels. Several features in the SMMUv3 + * architecture are not currently supported by the kernel for nesting: HTTU, + * BTM, MPAM and others. */ struct iommu_hw_info_arm_smmuv3 { __u32 flags;