Re: [PATCH v3 4/8] block: truncate: Don't make backing file data visible

2019-11-25 Thread Max Reitz
On 22.11.19 17:05, Kevin Wolf wrote: > When extending the size of an image that has a backing file larger than > its old size, make sure that the backing file data doesn't become > visible in the guest, but the added area is properly zeroed out. > > Consider the following scenario where the overla

Re: [PATCH v3 4/8] block: truncate: Don't make backing file data visible

2019-11-22 Thread Eric Blake
On 11/22/19 10:05 AM, Kevin Wolf wrote: When extending the size of an image that has a backing file larger than its old size, make sure that the backing file data doesn't become visible in the guest, but the added area is properly zeroed out. Consider the following scenario where the overlay is

[PATCH v3 4/8] block: truncate: Don't make backing file data visible

2019-11-22 Thread Kevin Wolf
When extending the size of an image that has a backing file larger than its old size, make sure that the backing file data doesn't become visible in the guest, but the added area is properly zeroed out. Consider the following scenario where the overlay is shorter than its backing file: base.q