On 06/11/2015 03:46 PM, Davidlohr Bueso wrote:
On Thu, 2015-06-11 at 14:01 -0700, Mike Kravetz wrote:/* Forward declaration */ static int hugetlb_acct_memory(struct hstate *h, long delta); @@ -3324,7 +3324,8 @@ static u32 fault_mutex_hash(struct hstate *h, struct mm_struct *mm, unsigned long key[2]; u32 hash; - if (vma->vm_flags & VM_SHARED) { + /* !vma implies this was called from hugetlbfs fallocate code */ + if (!vma || vma->vm_flags & VM_SHARED) {That !vma is icky, and really no need for it: hugetlbfs_fallocate(), for example, already passes [pseudo]vma->vm_flags with VM_SHARED, and you say it yourself in the comment. Do you see any reason why we cannot just keep the vma->vm_flags & VM_SHARED check?
Ah, I did not recall all the users of this code until I went to change it. The other user is truncate_hugapages() which will now be used for fallocate hole punch. Truncate like fallocate is an inode operation and there is no specific vma. I can create a pseudo-vma here as well just to pass the flag. I guess that would at least be consistent with the other user. -- Mike Kravetz -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>