diff options
author | Peter Maydell <peter.maydell@linaro.org> | 2021-07-10 19:55:20 +0100 |
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committer | Peter Maydell <peter.maydell@linaro.org> | 2021-07-10 19:55:21 +0100 |
commit | 42e1d798a6a01817bdcf722ac27eea01531e21cd (patch) | |
tree | 9c97b2ca0318c43e62c99753a57236b4fab788d6 /docs | |
parent | fc32b91a88cc9cd560da5488bdca4d69f2bac620 (diff) | |
parent | e60edf69e2f64e818466019313517a2e6d6b63f4 (diff) |
Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block layer patches
- Make blockdev-reopen stable
- Remove deprecated qemu-img backing file without format
- rbd: Convert to coroutines and add write zeroes support
- rbd: Updated MAINTAINERS
- export/fuse: Allow other users access to the export
- vhost-user: Fix backends without multiqueue support
- Fix drive-backup transaction endless drained section
# gpg: Signature made Fri 09 Jul 2021 13:49:22 BST
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (28 commits)
block: Make blockdev-reopen stable API
iotests: Test reopening multiple devices at the same time
block: Support multiple reopening with x-blockdev-reopen
block: Acquire AioContexts during bdrv_reopen_multiple()
block: Add bdrv_reopen_queue_free()
qcow2: Fix dangling pointer after reopen for 'file'
qemu-img: Improve error for rebase without backing format
qemu-img: Require -F with -b backing image
qcow2: Prohibit backing file changes in 'qemu-img amend'
blockdev: fix drive-backup transaction endless drained section
vhost-user: Fix backends without multiqueue support
MAINTAINERS: add block/rbd.c reviewer
block/rbd: fix type of task->complete
iotests/fuse-allow-other: Test allow-other
iotests/308: Test +w on read-only FUSE exports
export/fuse: Let permissions be adjustable
export/fuse: Give SET_ATTR_SIZE its own branch
export/fuse: Add allow-other option
export/fuse: Pass default_permissions for mount
util/uri: do not check argument of uri_free()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'docs')
-rw-r--r-- | docs/system/deprecated.rst | 32 | ||||
-rw-r--r-- | docs/system/removed-features.rst | 31 |
2 files changed, 31 insertions, 32 deletions
diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst index 94fb7dbf4e..6d438f1c8d 100644 --- a/docs/system/deprecated.rst +++ b/docs/system/deprecated.rst @@ -300,38 +300,6 @@ this CPU is also deprecated. Related binaries ---------------- -qemu-img amend to adjust backing file (since 5.1) -''''''''''''''''''''''''''''''''''''''''''''''''' - -The use of ``qemu-img amend`` to modify the name or format of a qcow2 -backing image is deprecated; this functionality was never fully -documented or tested, and interferes with other amend operations that -need access to the original backing image (such as deciding whether a -v3 zero cluster may be left unallocated when converting to a v2 -image). Rather, any changes to the backing chain should be performed -with ``qemu-img rebase -u`` either before or after the remaining -changes being performed by amend, as appropriate. - -qemu-img backing file without format (since 5.1) -'''''''''''''''''''''''''''''''''''''''''''''''' - -The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img -convert`` to create or modify an image that depends on a backing file -now recommends that an explicit backing format be provided. This is -for safety: if QEMU probes a different format than what you thought, -the data presented to the guest will be corrupt; similarly, presenting -a raw image to a guest allows a potential security exploit if a future -probe sees a non-raw image based on guest writes. - -To avoid the warning message, or even future refusal to create an -unsafe image, you must pass ``-o backing_fmt=`` (or the shorthand -``-F`` during create) to specify the intended backing format. You may -use ``qemu-img rebase -u`` to retroactively add a backing format to an -existing image. However, be aware that there are already potential -security risks to blindly using ``qemu-img info`` to probe the format -of an untrusted backing image, when deciding what format to add into -an existing image. - Backwards compatibility ----------------------- diff --git a/docs/system/removed-features.rst b/docs/system/removed-features.rst index 2b21bd39ab..28bb035043 100644 --- a/docs/system/removed-features.rst +++ b/docs/system/removed-features.rst @@ -491,6 +491,37 @@ topologies described with -smp include all possible cpus, i.e. The ``enforce-config-section`` property was replaced by the ``-global migration.send-configuration={on|off}`` option. +qemu-img amend to adjust backing file (removed in 6.1) +'''''''''''''''''''''''''''''''''''''''''''''''''''''' + +The use of ``qemu-img amend`` to modify the name or format of a qcow2 +backing image was never fully documented or tested, and interferes +with other amend operations that need access to the original backing +image (such as deciding whether a v3 zero cluster may be left +unallocated when converting to a v2 image). Any changes to the +backing chain should be performed with ``qemu-img rebase -u`` either +before or after the remaining changes being performed by amend, as +appropriate. + +qemu-img backing file without format (removed in 6.1) +''''''''''''''''''''''''''''''''''''''''''''''''''''' + +The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img +convert`` to create or modify an image that depends on a backing file +now requires that an explicit backing format be provided. This is +for safety: if QEMU probes a different format than what you thought, +the data presented to the guest will be corrupt; similarly, presenting +a raw image to a guest allows a potential security exploit if a future +probe sees a non-raw image based on guest writes. + +To avoid creating unsafe backing chains, you must pass ``-o +backing_fmt=`` (or the shorthand ``-F`` during create) to specify the +intended backing format. You may use ``qemu-img rebase -u`` to +retroactively add a backing format to an existing image. However, be +aware that there are already potential security risks to blindly using +``qemu-img info`` to probe the format of an untrusted backing image, +when deciding what format to add into an existing image. + Block devices ------------- |