Merge ~mwhudson/curtin:quick_zero-wipefs into curtin:master

[Michael Hudson-Doyle]

call wipefs -a -f in addition to zeroing in quick_zero

LP: #1997920

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:42fd0ba2e375911d521cbb7adc8abbf5c5200ae5
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review: Approve (continuous-integration)

[Dan Bungert (dbungert)]

Thanks! Wipefs is probably better than some sort of block-zero arms race with wherever future tools decide to put information.

review: Approve

diff --git a/curtin/block/__init__.py b/curtin/block/__init__.py
index a46c8ec..1f9bb60 100644
--- a/curtin/block/__init__.py
+++ b/curtin/block/__init__.py
@@ -1207,10 +1207,11 @@ def wipe_file(path, reader=None, buflen=4 * 1024 * 1024, exclusive=True):
 
 def quick_zero(path, partitions=True, exclusive=True):
     """
-    zero 1M at front, 1M at end, and 1M at front
+    call wipefs -a -f on path, then zero 1M at front, 1M at end
     if this is a block device and partitions is true, then
     zero 1M at front and end of each partition.
     """
+    util.subp(['wipefs', '--all', '--force', path])
     buflen = 1024
     count = 1024
     zero_size = buflen * count