On Thu, 3 Dec 2020 16:53:50 +0800 Liu Zixian <liuzixian4@xxxxxxxxxx> wrote: > On success, mmap should return the begin address of newly mapped area, > but patch "mm: mmap: merge vma after call_mmap() if possible" > set vm_start of newly merged vma to return value addr. > Users of mmap will get wrong address if vma is merged after call_mmap(). > We fix this by moving the assignment to addr before merging vma. Let's cc David and Jason, as they commented on v1. You cc'ed stable@xxxxxxxxxxxxxxx on the email, but there's no cc:stable@xxxxxxxxxxxxxxx in the changelog tags. There should be. Has this bug actually been observed at runtime, or is it a theoretical from-code-inspection thing?