migration: Remove "rs" parameter in migration_bitmap_sync_precopy

The global static variable ram_state in fact is referred to by the
"rs" parameter in migration_bitmap_sync_precopy. For ease of call

migration: Remove "rs" parameter in migration_bitmap_sync_precopy

The global static variable ram_state in fact is referred to by the
"rs" parameter in migration_bitmap_sync_precopy. For ease of calling
by the callees, use the global variable directly in
migration_bitmap_sync_precopy and remove "rs" parameter.

The migration_bitmap_sync_precopy will be exported in the next commit.

Signed-off-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/283c335d61463bf477160da91b24da45cdaf3e43.1729146786.git.yong.huang@smartx.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Move cpu-throttle.c from system to migration

Move cpu-throttle.c from system to migration since it's
only used for migration; this makes us avoid exporting the
util functions and variable

migration: Move cpu-throttle.c from system to migration

Move cpu-throttle.c from system to migration since it's
only used for migration; this makes us avoid exporting the
util functions and variables in misc.h but export them in
migration.h when implementing the periodic ramblock dirty
sync feature in the upcoming commits.

Since CPU throttle timers are only used in migration, move
their registry to migration_object_init.

Signed-off-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/c1b3efaa0cb49e03d422e9da97bdb65cc3d234d1.1729146786.git.yong.huang@smartx.com
[peterx: Fix build on MacOS on cocoa.m, not move cpu-throttle.h yet]
[peterx: Fix subject spelling, per pm215]
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Stop CPU throttling conditionally

Since CPU throttling only occurs when auto-converge
is on, stop it conditionally.

Signed-off-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Fabian

migration: Stop CPU throttling conditionally

Since CPU throttling only occurs when auto-converge
is on, stop it conditionally.

Signed-off-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/f0c787080bb9ab0c37952f0ca5bfaa525d5ddd14.1729146786.git.yong.huang@smartx.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Ensure vmstate_save() sets errp

migration/savevm.c contains some calls to vmstate_save() that are
followed by migrate_set_error() if the integer return value indicates an
error. migrate_

migration: Ensure vmstate_save() sets errp

migration/savevm.c contains some calls to vmstate_save() that are
followed by migrate_set_error() if the integer return value indicates an
error. migrate_set_error() requires that the `Error *` object passed to
it is set. Therefore, vmstate_save() is assumed to always set *errp on
error.

Right now, that assumption is not met: vmstate_save_state_v() (called
internally by vmstate_save()) will not set *errp if
vmstate_subsection_save() or vmsd->post_save() fail. Fix that by adding
an *errp parameter to vmstate_subsection_save(), and by generating a
generic error in case post_save() fails (as is already done for
pre_save()).

Without this patch, qemu will crash after vmstate_subsection_save() or
post_save() have failed inside of a vmstate_save() call (unless
migrate_set_error() then happen to discard the new error because
s->error is already set). This happens e.g. when receiving the state
from a virtio-fs back-end (virtiofsd) fails.

Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Link: https://lore.kernel.org/r/20241015170437.310358-1-hreitz@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Put thread names together with macros

Keep migration thread names together, so it's easier to see a list of all
possible migration threads.

Still two functional changes below besides the

migration: Put thread names together with macros

Keep migration thread names together, so it's easier to see a list of all
possible migration threads.

Still two functional changes below besides the macro defintions:

- There's one dirty rate thread that we overlooked before, now we add
that too and name it as "mig/dirtyrate" following the old rules.

- The old name "mig/src/rp-thr" has "-thr" but it may not be useful if
it's a thread name anyway, while "rp" can be slightly hard to read.
Taking this chance to rename it to "mig/src/return", hopefully a better
name.

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Acked-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Link: https://lore.kernel.org/r/20241011153652.517440-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Cleanup migrate_fd_cleanup() on accessing to_dst_file

The cleanup function can in many cases needs cleanup on its own.

The major thing we want to do here is not referencing to_dst_file w

migration: Cleanup migrate_fd_cleanup() on accessing to_dst_file

The cleanup function can in many cases needs cleanup on its own.

The major thing we want to do here is not referencing to_dst_file when
without the file mutex. When at it, touch things elsewhere too to make it
look slightly better in general.

One thing to mention is, migration_thread has its own "running" boolean, so
it doesn't need to rely on to_dst_file being non-NULL. Multifd has a
dependency so it needs to be skipped if to_dst_file is not yet set; add a
richer comment for such reason.

Resolves: Coverity CID 1527402
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240919163042.116767-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration/multifd: fix build error when qpl compression is enabled

The page_size member has been removed from the MultiFDSendParams
and MultiFDRecvParams. The function multifd_ram_page_size is used

migration/multifd: fix build error when qpl compression is enabled

The page_size member has been removed from the MultiFDSendParams
and MultiFDRecvParams. The function multifd_ram_page_size is used to
provide the page size in the multifd compressor.

Fixes: 90fa121c6c ("migration/multifd: Inline page_size and page_count")
Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
Link: https://lore.kernel.org/r/20241008104527.3516755-1-yuan1.liu@intel.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration/postcopy: Use uffd helpers

Use the uffd_copy_page, uffd_zero_page and uffd_wakeup helpers
rather than calling ioctl ourselves.

They return -errno on error, and print an error_report thems

migration/postcopy: Use uffd helpers

Use the uffd_copy_page, uffd_zero_page and uffd_wakeup helpers
rather than calling ioctl ourselves.

They return -errno on error, and print an error_report themselves.
I think this actually makes postcopy_place_page actually more
consistent in it's callers.

Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240919134626.166183-7-dave@treblig.org
[peterx: fix i386 build]
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Remove unused socket_send_channel_create_sync

socket_send_channel_create_sync only use was removed by
d0edb8a173 ("migration: Create the postcopy preempt channel asynchronously")

Remov

migration: Remove unused socket_send_channel_create_sync

socket_send_channel_create_sync only use was removed by
d0edb8a173 ("migration: Create the postcopy preempt channel asynchronously")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240919134626.166183-5-dave@treblig.org
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Deprecate zero-blocks capability

The zero-blocks capability was meant to be used along with the block
migration, which has been removed already in commit eef0bae3a7
("migration: Remove bl

migration: Deprecate zero-blocks capability

The zero-blocks capability was meant to be used along with the block
migration, which has been removed already in commit eef0bae3a7
("migration: Remove block migration").

Setting zero-blocks is currently a noop, but the outright removal of
the capability would cause and error in case some users are still
setting it. Put the capability through the deprecation process.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240919134626.166183-4-dave@treblig.org
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Remove unused migrate_zero_blocks

migrate_zero_blocks is unused since
eef0bae3a7 ("migration: Remove block migration")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <dave@treblig.o

migration: Remove unused migrate_zero_blocks

migrate_zero_blocks is unused since
eef0bae3a7 ("migration: Remove block migration")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240919134626.166183-3-dave@treblig.org
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Remove migrate_cap_set

migrate_cap_set has been unused since
18d154f575 ("migration: Remove 'blk/-b' option from migrate commands")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <d

migration: Remove migrate_cap_set

migrate_cap_set has been unused since
18d154f575 ("migration: Remove 'blk/-b' option from migrate commands")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240919134626.166183-2-dave@treblig.org
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration/multifd: Ensure packet->ramblock is null-terminated

Coverity points out that the current usage of strncpy to write the
ramblock name allows the field to not have an ending '\0' in case
ids

migration/multifd: Ensure packet->ramblock is null-terminated

Coverity points out that the current usage of strncpy to write the
ramblock name allows the field to not have an ending '\0' in case
idstr is already not null-terminated (e.g. if it's larger than 256
bytes).

This is currently harmless because the packet->ramblock field is never
touched again on the source side. The destination side reads only up
to the field's size from the stream and forces the last byte to be 0.

We're still open to a programming error in the future in case this
field is ever passed into a function that expects a null-terminated
string.

Change from strncpy to QEMU's pstrcpy, which puts a '\0' at the end of
the string and doesn't fill the extra space with zeros.

(there's no spillage between iterations of fill_packet because after
commit 87bb9e953e ("migration/multifd: Isolate ram pages packet data")
the packet is always zeroed before filling)

Resolves: Coverity CID 1560071
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240919150611.17074-1-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: fix -Werror=maybe-uninitialized false-positive

../migration/ram.c:1873:23: error: ‘dirty’ may be used uninitialized [-Werror=maybe-uninitialized]

When 'block' != NULL, 'dirty' is initial

migration: fix -Werror=maybe-uninitialized false-positive

../migration/ram.c:1873:23: error: ‘dirty’ may be used uninitialized [-Werror=maybe-uninitialized]

When 'block' != NULL, 'dirty' is initialized.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>

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migration: fix -Werror=maybe-uninitialized false-positives

../migration/dirtyrate.c:186:5: error: ‘records’ may be used uninitialized [-Werror=maybe-uninitialized]
../migration/dirtyrate.c:168:12: e

migration: fix -Werror=maybe-uninitialized false-positives

../migration/dirtyrate.c:186:5: error: ‘records’ may be used uninitialized [-Werror=maybe-uninitialized]
../migration/dirtyrate.c:168:12: error: ‘gen_id’ may be used uninitialized [-Werror=maybe-uninitialized]
../migration/migration.c:2273:5: error: ‘file’ may be used uninitialized [-Werror=maybe-uninitialized]

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Hyman Huang <yong.huang@smartx.com>

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migration: remove return after g_assert_not_reached()

This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
assertion me

migration: remove return after g_assert_not_reached()

This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
assertion mechanisms.

Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240919044641.386068-31-pierrick.bouvier@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>

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migration: replace assert(false) with g_assert_not_reached()

This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
asser

migration: replace assert(false) with g_assert_not_reached()

This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
assertion mechanisms.

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-ID: <20240919044641.386068-14-pierrick.bouvier@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>

show more ...

migration: replace assert(0) with g_assert_not_reached()

This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
assertion

migration: replace assert(0) with g_assert_not_reached()

This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
assertion mechanisms.

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240919044641.386068-5-pierrick.bouvier@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>

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migration/multifd: Fix rb->receivedmap cleanup race

Fix a segmentation fault in multifd when rb->receivedmap is cleared
too early.

After commit 5ef7e26bdb ("migration/multifd: solve zero page causi

migration/multifd: Fix rb->receivedmap cleanup race

Fix a segmentation fault in multifd when rb->receivedmap is cleared
too early.

After commit 5ef7e26bdb ("migration/multifd: solve zero page causing
multiple page faults"), multifd started using the rb->receivedmap
bitmap, which belongs to ram.c and is initialized and *freed* from the
ram SaveVMHandlers.

Multifd threads are live until migration_incoming_state_destroy(),
which is called after qemu_loadvm_state_cleanup(), leading to a crash
when accessing rb->receivedmap.

process_incoming_migration_co() ...
qemu_loadvm_state() multifd_nocomp_recv()
qemu_loadvm_state_cleanup() ramblock_recv_bitmap_set_offset()
rb->receivedmap = NULL set_bit_atomic(..., rb->receivedmap)
...
migration_incoming_state_destroy()
multifd_recv_cleanup()
multifd_recv_terminate_threads(NULL)

Move the loadvm cleanup into migration_incoming_state_destroy(), after
multifd_recv_cleanup() to ensure multifd threads have already exited
when rb->receivedmap is cleared.

Adjust the postcopy listen thread comment to indicate that we still
want to skip the cpu synchronization.

CC: qemu-stable@nongnu.org
Fixes: 5ef7e26bdb ("migration/multifd: solve zero page causing multiple page faults")
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240917185802.15619-3-farosas@suse.de
[peterx: added comment in migration_incoming_state_destroy()]
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration/savevm: Remove extra load cleanup calls

There are two qemu_loadvm_state_cleanup() calls that were introduced
when qemu_loadvm_state_setup() was still called before loading the
configuratio

migration/savevm: Remove extra load cleanup calls

There are two qemu_loadvm_state_cleanup() calls that were introduced
when qemu_loadvm_state_setup() was still called before loading the
configuration section, so there was state to be cleaned up if the
header checks failed.

However, commit 9e14b84908 ("migration/savevm: load_header before
load_setup") has moved that configuration section part to
qemu_loadvm_state_header() which now happens before
qemu_loadvm_state_setup().

Remove the cleanup calls that are now misplaced.

Note that we didn't use Fixes because it's benign to cleanup() even if
setup() is not invoked. So this patch is not needed for stable, as it
falls into cleanup category.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240917185802.15619-2-farosas@suse.de
[peterx: added last paragraph of commit message]
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration/multifd: Fix loop conditions in multifd_zstd_send_prepare and multifd_zstd_recv

GitHub's CodeQL reports four critical errors which are fixed by this commit:

Unsigned difference expres

migration/multifd: Fix loop conditions in multifd_zstd_send_prepare and multifd_zstd_recv

GitHub's CodeQL reports four critical errors which are fixed by this commit:

Unsigned difference expression compared to zero

An expression (u - v > 0) with unsigned values u, v is only false if u == v,
so all changed expressions did not work as expected.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Link: https://lore.kernel.org/r/20240910054138.1458555-1-sw@weilnetz.de
[peterx: Fix mangled email for author]
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration/multifd: Fix build for qatzip

The qatzip series was based on an older commit, it applied cleanly even
though it has conflicts. Neither CI nor myself found the build will break
as it's ski

migration/multifd: Fix build for qatzip

The qatzip series was based on an older commit, it applied cleanly even
though it has conflicts. Neither CI nor myself found the build will break
as it's skipped by default when qatzip library was missing.

Fix the build issues. No need to copy stable as it just landed 9.2.

Cc: Yichen Wang <yichen.wang@bytedance.com>
Cc: Bryan Zhang <bryan.zhang@bytedance.com>
Cc: Hao Xiang <hao.xiang@linux.dev>
Cc: Yuan Liu <yuan1.liu@intel.com>
Fixes: 80484f9459 ("migration: Introduce 'qatzip' compression method")
Link: https://lore.kernel.org/r/20240910210450.3835123-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Introduce 'qatzip' compression method

Adds support for 'qatzip' as an option for the multifd compression
method parameter, and implements using QAT for 'qatzip' compression and
decompress

migration: Introduce 'qatzip' compression method

Adds support for 'qatzip' as an option for the multifd compression
method parameter, and implements using QAT for 'qatzip' compression and
decompression.

Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Prasad Pandit <pjp@fedoraproject.org>
Signed-off-by: Bryan Zhang <bryan.zhang@bytedance.com>
Signed-off-by: Hao Xiang <hao.xiang@linux.dev>
Signed-off-by: Yichen Wang <yichen.wang@bytedance.com>
Link: https://lore.kernel.org/r/20240830232722.58272-5-yichen.wang@bytedance.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration: Add migration parameters for QATzip

Adds support for migration parameters to control QATzip compression
level.

Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Bryan Zhang

migration: Add migration parameters for QATzip

Adds support for migration parameters to control QATzip compression
level.

Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Bryan Zhang <bryan.zhang@bytedance.com>
Signed-off-by: Hao Xiang <hao.xiang@linux.dev>
Signed-off-by: Yichen Wang <yichen.wang@bytedance.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Prasad Pandit <pjp@fedoraproject.org>
Link: https://lore.kernel.org/r/20240830232722.58272-4-yichen.wang@bytedance.com
Signed-off-by: Peter Xu <peterx@redhat.com>

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migration/multifd: Add documentation for multifd methods

Add documentation clarifying the usage of the multifd methods. The
general idea is that the client code calls into multifd to trigger
send/re

migration/multifd: Add documentation for multifd methods

Add documentation clarifying the usage of the multifd methods. The
general idea is that the client code calls into multifd to trigger
send/recv of data and multifd then calls these hooks back from the
worker threads at opportune moments so the client can process a
portion of the data.

Suggested-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>

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