Re: [PATCH v6 17/17] RFC: mm: add mmu_notifier argument to follow_pfn
From: Jason Gunthorpe <jgg@ziepe.ca>
Date: 2020-11-20 18:31:14
Also in:
dri-devel, kvm, linux-media, linux-mm, linux-samsung-soc, lkml
On Thu, Nov 19, 2020 at 03:41:46PM +0100, Daniel Vetter wrote:
quoted hunk ↗ jump to hunk
@@ -4805,21 +4824,15 @@ EXPORT_SYMBOL(follow_pte_pmd); * Return: zero and the pfn at @pfn on success, -ve otherwise. */ int follow_pfn(struct vm_area_struct *vma, unsigned long address, - unsigned long *pfn) + unsigned long *pfn, struct mmu_notifier *subscription) { - int ret = -EINVAL; - spinlock_t *ptl; - pte_t *ptep; + if (WARN_ON(!subscription->mm)) + return -EINVAL; + if (WARN_ON(subscription->mm != vma->vm_mm)) + return -EINVAL;
These two things are redundant right? vma->vm_mm != NULL? BTW, why do we even have this for nommu? If the only caller is kvm, can you even compile kvm on nommu?? Jason _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel