diff options
Diffstat (limited to 'drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c')
| -rw-r--r-- | drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c index c623dae1e115..1ef7bbb4acf3 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c @@ -6,6 +6,7 @@ #include <linux/mm.h> #include <linux/mmu_context.h> #include <linux/mmu_notifier.h> +#include <linux/sched/mm.h> #include <linux/slab.h> #include "arm-smmu-v3.h" @@ -96,9 +97,14 @@ static struct arm_smmu_ctx_desc *arm_smmu_alloc_shared_cd(struct mm_struct *mm) struct arm_smmu_ctx_desc *cd; struct arm_smmu_ctx_desc *ret = NULL; + /* Don't free the mm until we release the ASID */ + mmgrab(mm); + asid = arm64_mm_context_get(mm); - if (!asid) - return ERR_PTR(-ESRCH); + if (!asid) { + err = -ESRCH; + goto out_drop_mm; + } cd = kzalloc(sizeof(*cd), GFP_KERNEL); if (!cd) { @@ -165,6 +171,8 @@ out_free_cd: kfree(cd); out_put_context: arm64_mm_context_put(mm); +out_drop_mm: + mmdrop(mm); return err < 0 ? ERR_PTR(err) : ret; } @@ -173,6 +181,7 @@ static void arm_smmu_free_shared_cd(struct arm_smmu_ctx_desc *cd) if (arm_smmu_free_asid(cd)) { /* Unpin ASID */ arm64_mm_context_put(cd->mm); + mmdrop(cd->mm); kfree(cd); } } |