From: Jason Gunthorpe <jgg@nvidia.com> mainline inclusion from mainline-v6.10-rc1 commit 13abe4faac4348da0cf1c4eeb2b1b39fcfdb4b8f category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IB4WDJ CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Avoid arm_smmu_attach_dev() having to undo the changes to the smmu_domain->devices list, acquire the cdptr earlier so we don't need to handle that error. Now there is a clear break in arm_smmu_attach_dev() where all the prep-work has been done non-disruptively and we commit to making the HW change, which cannot fail. This completes transforming arm_smmu_attach_dev() so that it does not disturb the HW if it fails. Tested-by: Nicolin Chen <nicolinc@nvidia.com> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Reviewed-by: Michael Shavit <mshavit@google.com> Reviewed-by: Nicolin Chen <nicolinc@nvidia.com> Reviewed-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/6-v9-5040dc602008+177d7-smmuv3_newapi_p2_jgg@nvidi... Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 24 +++++++-------------- 1 file changed, 8 insertions(+), 16 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 8698d68d7fdb..605a81c1f2e6 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2908,6 +2908,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) struct arm_smmu_device *smmu; struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); struct arm_smmu_master *master; + struct arm_smmu_cd *cdptr; if (!fwspec) return -ENOENT; @@ -2936,6 +2937,12 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) if (ret) return ret; + if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) { + cdptr = arm_smmu_alloc_cd_ptr(master, IOMMU_NO_PASID); + if (!cdptr) + return -ENOMEM; + } + /* * Prevent arm_smmu_share_asid() from trying to change the ASID * of either the old or new domain while we are working on it. @@ -2955,13 +2962,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) switch (smmu_domain->stage) { case ARM_SMMU_DOMAIN_S1: { struct arm_smmu_cd target_cd; - struct arm_smmu_cd *cdptr; - - cdptr = arm_smmu_alloc_cd_ptr(master, IOMMU_NO_PASID); - if (!cdptr) { - ret = -ENOMEM; - goto out_list_del; - } arm_smmu_make_s1_cd(&target_cd, master, smmu_domain); arm_smmu_write_cd_entry(master, IOMMU_NO_PASID, cdptr, @@ -2978,16 +2978,8 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) } arm_smmu_enable_ats(master, smmu_domain); - goto out_unlock; - -out_list_del: - spin_lock_irqsave(&smmu_domain->devices_lock, flags); - list_del_init(&master->domain_head); - spin_unlock_irqrestore(&smmu_domain->devices_lock, flags); - -out_unlock: mutex_unlock(&arm_smmu_asid_lock); - return ret; + return 0; } static int arm_smmu_attach_dev_ste(struct device *dev, -- 2.33.0