This is a note to let you know that I've just added the patch titled iommu/vt-d: Fix PASID leak in intel_svm_unbind_mm() to the 5.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iommu-vt-d-fix-pasid-leak-in-intel_svm_unbind_mm.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0fa53b848dc0bd654cab971a29f76dcaaf408903 Author: Fenghua Yu <fenghua.yu@xxxxxxxxx> Date: Sat Aug 28 15:06:21 2021 +0800 iommu/vt-d: Fix PASID leak in intel_svm_unbind_mm() [ Upstream commit a21518cb23a3c7d49bafcb59862fd389fd829d4b ] The mm->pasid will be used in intel_svm_free_pasid() after load_pasid() during unbinding mm. Clearing it in load_pasid() will cause PASID cannot be freed in intel_svm_free_pasid(). Additionally mm->pasid was updated already before load_pasid() during pasid allocation. No need to update it again in load_pasid() during binding mm. Don't update mm->pasid to avoid the issues in both binding mm and unbinding mm. Fixes: 4048377414162 ("iommu/vt-d: Use iommu_sva_alloc(free)_pasid() helpers") Reported-and-tested-by: Dave Jiang <dave.jiang@xxxxxxxxx> Co-developed-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx> Link: https://lore.kernel.org/r/20210826215918.4073446-1-fenghua.yu@xxxxxxxxx Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210828070622.2437559-2-baolu.lu@xxxxxxxxxxxxxxx Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index 4b9b3f35ba0e..ceeca633a5f9 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -516,9 +516,6 @@ static void load_pasid(struct mm_struct *mm, u32 pasid) { mutex_lock(&mm->context.lock); - /* Synchronize with READ_ONCE in update_pasid(). */ - smp_store_release(&mm->pasid, pasid); - /* Update PASID MSR on all CPUs running the mm's tasks. */ on_each_cpu_mask(mm_cpumask(mm), _load_pasid, NULL, true);