Commit Graph

108415 Commits

Author SHA1 Message Date
Markus Armbruster
8beaeed734 dump: Rename qmp_dump_guest_memory() parameter to match QAPI schema
The name of the second parameter differs between QAPI schema and C
implementation: it's @protocol in the former and @file in the latter.
Potentially confusing.  Change the C implementation to match the QAPI
schema.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20231031104531.3169721-2-armbru@redhat.com>
2023-11-02 18:40:47 +04:00
Stephen Brennan
e6549197f7 dump: Add command interface for kdump-raw formats
The QMP dump API represents the dump format as an enumeration. Add three
new enumerators, one for each supported kdump compression, each named
"kdump-raw-*".

For the HMP command line, rather than adding a new flag corresponding to
each format, it seems more human-friendly to add a single flag "-R" to
switch the kdump formats to "raw" mode. The choice of "-R" also
correlates nicely to the "makedumpfile -R" option, which would serve to
reassemble a flattened vmcore.

Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
[ Marc-André: replace loff_t with off_t, indent fixes ]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20230918233233.1431858-4-stephen.s.brennan@oracle.com>
2023-11-02 18:40:37 +04:00
Stephen Brennan
d43a01db28 dump: Allow directly outputting raw kdump format
The flattened format (currently output by QEMU) is used by makedumpfile
only when it is outputting a vmcore to a file which is not seekable. The
flattened format functions essentially as a set of instructions of the
form "seek to the given offset, then write the given bytes out".

The flattened format can be reconstructed using makedumpfile -R, or
makedumpfile-R.pl, but it is a slow process because it requires copying
the entire vmcore. The flattened format can also be directly read by
crash, but still, it requires a lengthy reassembly phase.

To sum up, the flattened format is not an ideal one: it should only be
used on files which are actually not seekable. This is the exact
strategy which makedumpfile uses, as seen in the implementation of
"write_buffer()" in makedumpfile [1]. However, QEMU has always used the
flattened format. For compatibility it is best not to change the default
output format without warning. So, add a flag to DumpState which changes
the output to use the normal (i.e. raw) format. This flag will be added
to the QMP and HMP commands in the next change.

[1]: f23bb94356/makedumpfile.c (L5008-L5040)

Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
[ Marc-André: replace loff_t with off_t ]
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20230918233233.1431858-3-stephen.s.brennan@oracle.com>
2023-11-02 18:05:02 +04:00
Stephen Brennan
4d7dd4ed4f dump: Pass DumpState to write_ functions
For the next patch, we need a reference to DumpState when writing data.

Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20230918233233.1431858-2-stephen.s.brennan@oracle.com>
2023-11-02 17:40:52 +04:00
Stefan Hajnoczi
6c9ae1ce82 Block layer patches
- virtio-blk: use blk_io_plug_call() instead of notification BH
 - mirror: allow switching from background to active mode
 - qemu-img rebase: add compression support
 - Fix locking in media change monitor commands
 - Fix a few blockjob-related deadlocks when using iothread
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Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- virtio-blk: use blk_io_plug_call() instead of notification BH
- mirror: allow switching from background to active mode
- qemu-img rebase: add compression support
- Fix locking in media change monitor commands
- Fix a few blockjob-related deadlocks when using iothread

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# gpg: Signature made Wed 01 Nov 2023 03:58:09 JST
# 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

* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (27 commits)
  iotests: add test for changing mirror's copy_mode
  mirror: return mirror-specific information upon query
  blockjob: query driver-specific info via a new 'query' driver method
  qapi/block-core: turn BlockJobInfo into a union
  qapi/block-core: use JobType for BlockJobInfo's type
  mirror: implement mirror_change method
  block/mirror: determine copy_to_target only once
  block/mirror: move dirty bitmap to filter
  block/mirror: set actively_synced even after the job is ready
  blockjob: introduce block-job-change QMP command
  virtio-blk: remove batch notification BH
  virtio: use defer_call() in virtio_irqfd_notify()
  util/defer-call: move defer_call() to util/
  block: rename blk_io_plug_call() API to defer_call()
  blockdev: mirror: avoid potential deadlock when using iothread
  block: avoid potential deadlock during bdrv_graph_wrlock() in bdrv_close()
  blockjob: drop AioContext lock before calling bdrv_graph_wrlock()
  iotests: Test media change with iothreads
  block: Fix locking in media change monitor commands
  iotests: add tests for "qemu-img rebase" with compression
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-11-01 06:58:11 +09:00
Stefan Hajnoczi
997ef293d2 Maintainer updates for testing, gitlab, gdbstub and plugins:
- add dtc package to openbsd VMs
   - use -fno-stack-protector for non-stdlib tests
   - split alpha and sh4 compilers into legacy image
   - harmonise other compilers into debian-all-test-cross
   - fix NULL check in gdb_regs
   - fix memleak in semihosting
   - remove unused parameter in plugin code
   - fix fd leak in lockstep plugin
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Merge tag 'pull-halloween-omnibus-311023-2' of https://gitlab.com/stsquad/qemu into staging

Maintainer updates for testing, gitlab, gdbstub and plugins:

  - add dtc package to openbsd VMs
  - use -fno-stack-protector for non-stdlib tests
  - split alpha and sh4 compilers into legacy image
  - harmonise other compilers into debian-all-test-cross
  - fix NULL check in gdb_regs
  - fix memleak in semihosting
  - remove unused parameter in plugin code
  - fix fd leak in lockstep plugin

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# gpg: Signature made Tue 31 Oct 2023 23:11:00 JST
# gpg:                using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* tag 'pull-halloween-omnibus-311023-2' of https://gitlab.com/stsquad/qemu:
  contrib/plugins: Close file descriptor on error return
  plugins: Remove an extra parameter
  semihosting: fix memleak at semihosting_arg_fallback
  gdbstub: Check if gdb_regs is NULL
  tests/docker: upgrade debian-all-test-cross to bookworm
  tests/docker: use debian-all-test-cross for sparc64
  tests/docker: use debian-all-test-cross for riscv64
  tests/docker: use debian-all-test-cross for mips
  tests/docker: use debian-all-test-cross for mips64
  tests/docker: use debian-all-test-cross for m68k
  tests/docker: use debian-all-test-cross for hppa
  tests/docker: use debian-all-test-cross for power
  tests/docker: move sh4 to use debian-legacy-test-cross
  tests/docker: use debian-legacy-test-cross for alpha
  gitlab: add build-loongarch to matrix
  gitlab: clean-up build-soft-softmmu job
  gitlab: split alpha testing into a legacy container
  tests/tcg: Add -fno-stack-protector
  tests/vm/openbsd: Use the system dtc package

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-11-01 06:57:29 +09:00
Stefan Hajnoczi
f13b978cc7 Migration Pull request (20231031)
Hi
 
 This is repeat of the Migration PULL for 20231020.
 - I removed vmstate_register(big problems with s390x)
 - I added yet more countes (juan)
 
 CI: https://gitlab.com/juan.quintela/qemu/-/pipelines/1055797950
 
 Please apply.
 
 Thanks, Juan.
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Merge tag 'migration-20231031-pull-request' of https://gitlab.com/juan.quintela/qemu into staging

Migration Pull request (20231031)

Hi

This is repeat of the Migration PULL for 20231020.
- I removed vmstate_register(big problems with s390x)
- I added yet more countes (juan)

CI: https://gitlab.com/juan.quintela/qemu/-/pipelines/1055797950

Please apply.

Thanks, Juan.

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# gpg: Signature made Tue 31 Oct 2023 18:01:26 JST
# gpg:                using RSA key 1899FF8EDEBF58CCEE034B82F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>" [full]
# gpg:                 aka "Juan Quintela <quintela@trasno.org>" [full]
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* tag 'migration-20231031-pull-request' of https://gitlab.com/juan.quintela/qemu: (38 commits)
  qemu-file: Make qemu_fflush() return errors
  migration: Remove transferred atomic counter
  migration: Use migration_transferred_bytes()
  qemu-file: Simplify qemu_file_get_error()
  migration: migration_rate_limit_reset() don't need the QEMUFile
  migration: migration_transferred_bytes() don't need the QEMUFile
  qemu-file: Remove _noflush from qemu_file_transferred_noflush()
  qemu_file: Remove unused qemu_file_transferred()
  migration: Use the number of transferred bytes directly
  qemu_file: total_transferred is not used anymore
  qemu_file: Use a stat64 for qemu_file_transferred
  qemu-file: Don't increment qemu_file_transferred at qemu_file_fill_buffer
  migration: Stop migration immediately in RDMA error paths
  migration: Deprecate old compression method
  migration: Deprecate block migration
  migration: migrate 'blk' command option is deprecated.
  migration: migrate 'inc' command option is deprecated.
  qemu-iotests: Filter warnings about block migration being deprecated
  migration: set file error on subsection loading
  migration: rename vmstate_save_needed->vmstate_section_needed
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-11-01 06:56:53 +09:00
Fiona Ebner
900e7d413d iotests: add test for changing mirror's copy_mode
One part of the test is using a throttled source to ensure that there
are no obvious issues when changing the copy_mode while there are
ongoing requests (source and target images are compared at the very
end).

The other part of the test is using a throttled target to ensure that
the change to active mode actually happened. This is done by hitting
the throttling limit, issuing a synchronous write and then immediately
verifying the target side. QSD is used, because otherwise, a
synchronous write would hang there.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231031135431.393137-11-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 19:46:51 +01:00
Fiona Ebner
76cb2f2491 mirror: return mirror-specific information upon query
To start out, only actively-synced is returned.

For example, this is useful for jobs that started out in background
mode and switched to active mode. Once actively-synced is true, it's
clear that the mode switch has been completed. Note that completion of
the switch might happen much earlier, e.g. if the switch happens
before the job is ready, once all background operations have finished.
It's assumed that whether the disks are actively-synced or not is more
interesting than whether the mode switch completed. That information
can still be added if required in the future.

In presence of an iothread, the actively_synced member is now shared
between the iothread and the main thread, so turn accesses to it
atomic.

Requires to adapt the output for iotest 109.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231031135431.393137-10-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:29 +01:00
Fiona Ebner
59fd82544d blockjob: query driver-specific info via a new 'query' driver method
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231031135431.393137-9-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:29 +01:00
Fiona Ebner
701efc9f2d qapi/block-core: turn BlockJobInfo into a union
In preparation to additionally return job-type-specific information.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20231031135431.393137-8-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:29 +01:00
Fiona Ebner
d67c54d05f qapi/block-core: use JobType for BlockJobInfo's type
In preparation to turn BlockJobInfo into a union with @type as the
discriminator. That requires it to be an enum. Even without that
requirement, it's nicer to have an enum instead of a str here.

No functional change is intended.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20231031135431.393137-7-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:29 +01:00
Fiona Ebner
2d400d15a0 mirror: implement mirror_change method
which allows switching the @copy-mode from 'background' to
'write-blocking'.

This is useful for management applications, so they can start out in
background mode to avoid limiting guest write speed and switch to
active mode when certain criteria are fulfilled.

In presence of an iothread, the copy_mode member is now shared between
the iothread and the main thread, so turn accesses to it atomic.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231031135431.393137-6-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:29 +01:00
Fiona Ebner
7b32ad2242 block/mirror: determine copy_to_target only once
In preparation to allow changing the copy_mode via QMP. When running
in an iothread, it could be that copy_mode is changed from the main
thread in between reading copy_mode in bdrv_mirror_top_pwritev() and
reading copy_mode in bdrv_mirror_top_do_write(), so they might end up
disagreeing about whether copy_to_target is true or false. Avoid that
scenario by determining copy_to_target only once and passing it to
bdrv_mirror_top_do_write() as an argument.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20231031135431.393137-5-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:29 +01:00
Fiona Ebner
058cfca564 block/mirror: move dirty bitmap to filter
In preparation to allow switching to active mode without draining.
Initialization of the bitmap in mirror_dirty_init() still happens with
the original/backing BlockDriverState, which should be fine, because
the mirror top has the same length.

Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231031135431.393137-4-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:29 +01:00
Fiona Ebner
c45d0e1af0 block/mirror: set actively_synced even after the job is ready
In preparation to allow switching from background to active mode. This
ensures that setting actively_synced will not be missed when the
switch happens after the job is ready.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20231031135431.393137-3-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:29 +01:00
Fiona Ebner
61a3a5a76a blockjob: introduce block-job-change QMP command
which will allow changing job-type-specific options after job
creation.

In the JobVerbTable, the same allow bits as for set-speed are used,
because set-speed can be considered an existing change command.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20231031135431.393137-2-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 18:20:25 +01:00
Stefan Hajnoczi
073458da56 virtio-blk: remove batch notification BH
There is a batching mechanism for virtio-blk Used Buffer Notifications
that is no longer needed because the previous commit added batching to
virtio_notify_irqfd().

Note that this mechanism was rarely used in practice because it is only
enabled when EVENT_IDX is not negotiated by the driver. Modern drivers
enable EVENT_IDX.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230913200045.1024233-5-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 15:42:17 +01:00
Stefan Hajnoczi
84d61e5f36 virtio: use defer_call() in virtio_irqfd_notify()
virtio-blk and virtio-scsi invoke virtio_irqfd_notify() to send Used
Buffer Notifications from an IOThread. This involves an eventfd
write(2) syscall. Calling this repeatedly when completing multiple I/O
requests in a row is wasteful.

Use the defer_call() API to batch together virtio_irqfd_notify() calls
made during thread pool (aio=threads), Linux AIO (aio=native), and
io_uring (aio=io_uring) completion processing.

Behavior is unchanged for emulated devices that do not use
defer_call_begin()/defer_call_end() since defer_call() immediately
invokes the callback when called outside a
defer_call_begin()/defer_call_end() region.

fio rw=randread bs=4k iodepth=64 numjobs=8 IOPS increases by ~9% with a
single IOThread and 8 vCPUs. iodepth=1 decreases by ~1% but this could
be noise. Detailed performance data and configuration specifics are
available here:
https://gitlab.com/stefanha/virt-playbooks/-/tree/blk_io_plug-irqfd

This duplicates the BH that virtio-blk uses for batching. The next
commit will remove it.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230913200045.1024233-4-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 15:42:14 +01:00
Stefan Hajnoczi
433fcea40c util/defer-call: move defer_call() to util/
The networking subsystem may wish to use defer_call(), so move the code
to util/ where it can be reused.

As a reminder of what defer_call() does:

This API defers a function call within a defer_call_begin()/defer_call_end()
section, allowing multiple calls to batch up. This is a performance
optimization that is used in the block layer to submit several I/O requests
at once instead of individually:

  defer_call_begin(); <-- start of section
  ...
  defer_call(my_func, my_obj); <-- deferred my_func(my_obj) call
  defer_call(my_func, my_obj); <-- another
  defer_call(my_func, my_obj); <-- another
  ...
  defer_call_end(); <-- end of section, my_func(my_obj) is called once

Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230913200045.1024233-3-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 15:41:42 +01:00
Stefan Hajnoczi
ccee48aa73 block: rename blk_io_plug_call() API to defer_call()
Prepare to move the blk_io_plug_call() API out of the block layer so
that other subsystems call use this deferred call mechanism. Rename it
to defer_call() but leave the code in block/plug.c.

The next commit will move the code out of the block layer.

Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Paul Durrant <paul@xen.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230913200045.1024233-2-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 15:41:24 +01:00
Cong Liu
7f45276269 contrib/plugins: Close file descriptor on error return
This patch closes the file descriptor fd on error return to avoid
resource leak.

Fixes: ec7ee95db9 ("contrib/plugins: fix coverity warning in lockstep")
Signed-off-by: Cong Liu <liucong2@kylinos.cn>
Message-Id: <20231018025225.1640122-1-liucong2@kylinos.cn>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-20-alex.bennee@linaro.org>
2023-10-31 14:10:21 +00:00
Akihiko Odaki
946bf79e40 plugins: Remove an extra parameter
copy_call() has an unused parameter so remove it.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20231019101030.128431-7-akihiko.odaki@daynix.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231029145033.592566-19-alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2023-10-31 14:10:21 +00:00
Matheus Tavares Bernardino
2eb71a0c20 semihosting: fix memleak at semihosting_arg_fallback
We duplicate "cmd" as strtok may modify its argument, but we forgot
to free it later. Furthermore, add_semihosting_arg doesn't take
responsibility for this memory either (it strdup's the argument).

Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <03d81c56bfc3d08224e4106efca5949d8894cfa5.1697801632.git.quic_mathbern@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-18-alex.bennee@linaro.org>
2023-10-31 14:10:21 +00:00
Akihiko Odaki
dbd6623ce7 gdbstub: Check if gdb_regs is NULL
cpu->gdb_regs may be NULL if no coprocessor is registered.

Fixes: 73c392c26b ("gdbstub: Replace gdb_regs with an array")
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20231029145033.592566-17-alex.bennee@linaro.org>
Message-Id: <20231019101030.128431-2-akihiko.odaki@daynix.com>
Tested-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2023-10-31 14:10:21 +00:00
Alex Bennée
aba77ac5db tests/docker: upgrade debian-all-test-cross to bookworm
This requires a few more tweaks than usual as:

  - the default sources format has changed
  - bring in python3-tomli from the repos
  - split base install from cross compilers
  - also include libclang-rt-dev for sanitiser builds

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-16-alex.bennee@linaro.org>
2023-10-31 14:10:21 +00:00
Alex Bennée
7ccb4153fe tests/docker: use debian-all-test-cross for sparc64
Maintaining two sets of containers for test building is silly. While
it makes sense for the QEMU cross-compile targets to have their own
fat containers built by lcitool we might as well merge the other
random debian based compilers into the same one used on gitlab.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-15-alex.bennee@linaro.org>
2023-10-31 14:10:21 +00:00
Alex Bennée
26025d8e36 tests/docker: use debian-all-test-cross for riscv64
Maintaining two sets of containers for test building is silly. While
it makes sense for the QEMU cross-compile targets to have their own
fat containers built by lcitool we might as well merge the other
random debian based compilers into the same one used on gitlab.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-14-alex.bennee@linaro.org>
2023-10-31 14:10:14 +00:00
Alex Bennée
b09bb6d1b8 tests/docker: use debian-all-test-cross for mips
Maintaining two sets of containers for test building is silly. While
it makes sense for the QEMU cross-compile targets to have their own
fat containers built by lcitool we might as well merge the other
random debian based compilers into the same one used on gitlab.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-13-alex.bennee@linaro.org>
2023-10-31 14:10:14 +00:00
Alex Bennée
92a3165e1a tests/docker: use debian-all-test-cross for mips64
Maintaining two sets of containers for test building is silly. While
it makes sense for the QEMU cross-compile targets to have their own
fat containers built by lcitool we might as well merge the other
random debian based compilers into the same one used on gitlab.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-12-alex.bennee@linaro.org>
2023-10-31 14:10:14 +00:00
Alex Bennée
9d9a573612 tests/docker: use debian-all-test-cross for m68k
Maintaining two sets of containers for test building is silly. While
it makes sense for the QEMU cross-compile targets to have their own
fat containers built by lcitool we might as well merge the other
random debian based compilers into the same one used on gitlab.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-11-alex.bennee@linaro.org>
2023-10-31 14:10:14 +00:00
Alex Bennée
95f5bf9521 tests/docker: use debian-all-test-cross for hppa
Maintaining two sets of containers for test building is silly. While
it makes sense for the QEMU cross-compile targets to have their own
fat containers built by lcitool we might as well merge the other
random debian based compilers into the same one used on gitlab.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-10-alex.bennee@linaro.org>
2023-10-31 14:10:14 +00:00
Alex Bennée
eb4cb4ed1f tests/docker: use debian-all-test-cross for power
Maintaining two sets of containers for test building is silly. While
it makes sense for the QEMU cross-compile targets to have their own
fat containers built by lcitool we might as well merge the other
random debian based compilers into the same one used on gitlab.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-9-alex.bennee@linaro.org>
2023-10-31 14:10:06 +00:00
Alex Bennée
4e76d98ae9 tests/docker: move sh4 to use debian-legacy-test-cross
sh4 is another target which doesn't work with bookworm compilers. To
keep on buster move across to the debian-legacy-test-cross image and
update accordingly.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231030135715.800164-1-alex.bennee@linaro.org>
2023-10-31 13:28:34 +00:00
Alex Bennée
d004e27b4e tests/docker: use debian-legacy-test-cross for alpha
Maintaining two sets of containers for test building is silly. While
it makes sense for the QEMU cross-compile targets to have their own
fat containers built by lcitool we might as well merge the other
random debian based compilers into the same one used on gitlab.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-7-alex.bennee@linaro.org>
2023-10-31 13:28:30 +00:00
Alex Bennée
cb8715bf0c gitlab: add build-loongarch to matrix
We have the compiler and with a few updates a container that can build
QEMU so we should at least run the check-tcg smoke tests.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-6-alex.bennee@linaro.org>
2023-10-31 13:28:30 +00:00
Alex Bennée
6f6c399976 gitlab: clean-up build-soft-softmmu job
Having dropped alpha we also now drop xtensa as we don't have the
compiler in this image. It's not all doom and gloom though as a number
of other targets have gained softmmu TCG tests so we can add them. We
will take care of the other targets with their own containers in
future commits.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-5-alex.bennee@linaro.org>
2023-10-31 13:28:30 +00:00
Alex Bennée
aa39c4c098 gitlab: split alpha testing into a legacy container
The current bookworm compiler doesn't build the static binaries due to
bug #1054412 and it might be awhile before it gets fixed. The problem
of keeping older architecture compilers running isn't going to go away
so lets prepare the ground. Create a legacy container and move some
tests around so the others can get upgraded.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-4-alex.bennee@linaro.org>
2023-10-31 13:28:25 +00:00
Akihiko Odaki
580731dcc8 tests/tcg: Add -fno-stack-protector
A build of GCC 13.2 will have stack protector enabled by default if it
was configured with --enable-default-ssp option. For such a compiler,
it is necessary to explicitly disable stack protector when linking
without standard libraries.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230731091042.139159-3-akihiko.odaki@daynix.com>
[AJB: fix comment string typo]
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-3-alex.bennee@linaro.org>
2023-10-31 13:28:19 +00:00
Thomas Huth
05c223cef7 tests/vm/openbsd: Use the system dtc package
We can use the pre-packaged libfdt from the dtc package to avoid
that we have to compile this code each time again and again.

While we're at it, the "--python=python3" does not seemt to be
necessary anymore, so we can drop it.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20231016154049.37147-1-thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231029145033.592566-2-alex.bennee@linaro.org>
2023-10-31 13:28:13 +00:00
Fiona Ebner
302823854b blockdev: mirror: avoid potential deadlock when using iothread
The bdrv_getlength() function is a generated co-wrapper and uses
AIO_WAIT_WHILE() to wait for the spawned coroutine. AIO_WAIT_WHILE()
expects the lock to be acquired exactly once.

Fix a case where it may be acquired twice. This can happen when the
source node is explicitly specified as the @replaces parameter or if the
source node is a filter node.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231019131936.414246-4-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:36 +01:00
Fiona Ebner
e462c6d27d block: avoid potential deadlock during bdrv_graph_wrlock() in bdrv_close()
by passing the BlockDriverState along, so the held AioContext can be
dropped before polling. See commit 31b2ddfea3 ("graph-lock: Unlock the
AioContext while polling") which introduced this functionality for
more information.

The only way to reach bdrv_close() is via bdrv_unref() and for calling
that the BlockDriverState's AioContext lock is supposed to be held.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231019131936.414246-3-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:36 +01:00
Fiona Ebner
67446e605d blockjob: drop AioContext lock before calling bdrv_graph_wrlock()
Same rationale as in 31b2ddfea3 ("graph-lock: Unlock the AioContext
while polling"). Otherwise, a deadlock can happen.

The alternative would be to pass a BlockDriverState along to
bdrv_graph_wrlock(), but there is no BlockDriverState readily
available and it's also better conceptually, because the lock is held
for the job.

The function is always called with the job's AioContext lock held, via
one of the .abort, .clean, .free or .prepare job driver functions.
Thus, it's safe to drop it.

While mirror_exit_common() does hold a second AioContext lock while
calling block_job_remove_all_bdrv(), that is for the main thread's
AioContext and does not need to be dropped (bdrv_graph_wrlock(bs) also
skips dropping the lock if bdrv_get_aio_context(bs) ==
qemu_get_aio_context()).

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20231019131936.414246-2-f.ebner@proxmox.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:36 +01:00
Kevin Wolf
3be5762294 iotests: Test media change with iothreads
iotests case 118 already tests all relevant operations for media change
with multiple devices, however never with iothreads. This changes the
test so that the virtio-scsi tests run with an iothread.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231013153302.39234-3-kwolf@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:33 +01:00
Kevin Wolf
fed8245015 block: Fix locking in media change monitor commands
blk_insert_bs() requires that the caller holds the AioContext lock for
the node to be inserted. Since commit c066e808e1, neglecting to do so
causes a crash when the child has to be moved to a different AioContext
to attach it to the BlockBackend.

This fixes qmp_blockdev_insert_anon_medium(), which is called for the
QMP commands 'blockdev-insert-medium' and 'blockdev-change-medium', to
correctly take the lock.

Cc: qemu-stable@nongnu.org
Fixes: https://issues.redhat.com/browse/RHEL-3922
Fixes: c066e808e1
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231013153302.39234-2-kwolf@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:28 +01:00
Andrey Drobyshev
87fe52ceca iotests: add tests for "qemu-img rebase" with compression
The test cases considered so far:

314 (new test suite):

1. Check that compression mode isn't compatible with "-f raw" (raw
   format doesn't support compression).
2. Check that rebasing an image onto no backing file preserves the data
   and writes the copied clusters actually compressed.
3. Same as 2, but with a raw backing file (i.e. the clusters copied from the
   backing are originally uncompressed -- we check they end up compressed
   after being merged).
4. Remove a single delta from a backing chain, perform the same checks
   as in 2.
5. Check that even when backing and overlay are initially uncompressed,
   copied clusters end up compressed when rebase with compression is
   performed.

271:

1. Check that when target image has subclusters, rebase with compression
   will make an entire cluster containing the written subcluster
   compressed.

Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Message-ID: <20230919165804.439110-9-andrey.drobyshev@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:28 +01:00
Andrey Drobyshev
26ea27898b qemu-img: add compression option to rebase subcommand
If we rebase an image whose backing file has compressed clusters, we
might end up wasting disk space since the copied clusters are now
uncompressed.  In order to have better control over this, let's add
"--compress" option to the "qemu-img rebase" command.

Note that this option affects only the clusters which are actually being
copied from the original backing file.  The clusters which were
uncompressed in the target image will remain so.

Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Message-ID: <20230919165804.439110-8-andrey.drobyshev@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:28 +01:00
Andrey Drobyshev
f93e65ee51 iotests/{024, 271}: add testcases for qemu-img rebase
As the previous commit changes the logic of "qemu-img rebase" (it's using
write alignment now), let's add a couple more test cases which would
ensure it works correctly.  In particular, the following scenarios:

024: add test case for rebase within one backing chain when the overlay
     cluster size > backings cluster size;
271: add test case for rebase images that contain subclusters.  Check
     that no extra allocations are being made.

Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Message-ID: <20230919165804.439110-7-andrey.drobyshev@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:28 +01:00
Andrey Drobyshev
12df580b3b qemu-img: rebase: avoid unnecessary COW operations
When rebasing an image from one backing file to another, we need to
compare data from old and new backings.  If the diff between that data
happens to be unaligned to the target cluster size, we might end up
doing partial writes, which would lead to copy-on-write and additional IO.

Consider the following simple case (virtual_size == cluster_size == 64K):

base <-- inc1 <-- inc2

qemu-io -c "write -P 0xaa 0 32K" base.qcow2
qemu-io -c "write -P 0xcc 32K 32K" base.qcow2
qemu-io -c "write -P 0xbb 0 32K" inc1.qcow2
qemu-io -c "write -P 0xcc 32K 32K" inc1.qcow2
qemu-img rebase -f qcow2 -b base.qcow2 -F qcow2 inc2.qcow2

While doing rebase, we'll write a half of the cluster to inc2, and block
layer will have to read the 2nd half of the same cluster from the base image
inc1 while doing this write operation, although the whole cluster is already
read earlier to perform data comparison.

In order to avoid these unnecessary IO cycles, let's make sure every
write request is aligned to the overlay subcluster boundaries.  Using
subcluster size is universal as for the images which don't have them
this size equals to the cluster size. so in any case we end up aligning
to the smallest unit of allocation.

Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
Message-ID: <20230919165804.439110-6-andrey.drobyshev@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:28 +01:00
Andrey Drobyshev
c20c8ae700 qemu-img: add chunk size parameter to compare_buffers()
Add @chsize param to the function which, if non-zero, would represent
the chunk size to be used for comparison.  If it's zero, then
BDRV_SECTOR_SIZE is used as default chunk size, which is the previous
behaviour.

In particular, we're going to use this param in img_rebase() to make the
write requests aligned to a predefined alignment value.

Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Message-ID: <20230919165804.439110-5-andrey.drobyshev@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-31 13:51:28 +01:00