Taking the mutex every time for each dirty bit to clear is too slow, especially
we'll take/release even if the dirty bit is cleared. So far it's only used to
sync with special cases with qemu_guest_free_page_hint() against migration
thread, nothing really that serious yet. Let's move the lock to be upper.
There're two callers of migration_bitmap_clear_dirty().
For migration, move it into ram_save_iterate(). With the help of MAX_WAIT
logic, we'll only run ram_save_iterate() for no more than 50ms-ish time, so
taking the lock once there at the entry. It also means any call sites to
qemu_guest_free_page_hint() can be delayed; but it should be very rare, only
during migration, and I don't see a problem with it.
For COLO, move it up to colo_flush_ram_cache(). I think COLO forgot to take
that lock even when calling ramblock_sync_dirty_bitmap(), where another example
is migration_bitmap_sync() who took it right. So let the mutex cover both the
ramblock_sync_dirty_bitmap() and migration_bitmap_clear_dirty() calls.
It's even possible to drop the lock so we use atomic operations upon rb->bmap
and the variable migration_dirty_pages. I didn't do it just to still be safe,
also not predictable whether the frequent atomic ops could bring overhead too
e.g. on huge vms when it happens very often. When that really comes, we can
keep a local counter and periodically call atomic ops. Keep it simple for now.
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hailiang Zhang <zhang.zhanghailiang@huawei.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: Leonardo Bras Soares Passos <lsoaresp@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210630200805.280905-1-peterx@redhat.com>
Reviewed-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
For each "migrate" command, remember to clear the s->error before going on.
For one reason, when there's a new error it'll be still remembered; see
migrate_set_error() who only sets the error if error==NULL. Meanwhile if a
failed migration completes (e.g., postcopy recovered and finished), we
shouldn't dump an error when calling migrate_fd_cleanup() at last.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210708190653.252961-4-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Below process could crash qemu with postcopy recovery:
1. (hmp) migrate -d ..
2. (hmp) migrate_start_postcopy
3. [network down, postcopy paused]
4. (hmp) migrate -r $WRONG_PORT
when try the recover on an invalid $WRONG_PORT, cleanup_bh will be cleared
5. (hmp) migrate -r $RIGHT_PORT
[qemu crash on assert(cleanup_bh)]
The thing is we shouldn't cleanup if it's postcopy resume; the error is set
mostly because the channel is wrong, so we return directly waiting for the user
to retry.
migrate_fd_cleanup() should only be called when migration is cancelled or
completed.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210708190653.252961-3-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
When postcopy pause triggered, we rely on the migration thread to cleanup the
to_dst_file handle, and the return path thread to cleanup the from_dst_file
handle (which is stored in the local variable "rp").
Within the process, from_dst_file cleanup (qemu_fclose) is postponed until it's
setup again due to a postcopy recovery.
It used to work before yank was born; after yank is introduced we rely on the
refcount of IOC to correctly unregister yank function in channel_close(). If
without the early and on-time release of from_dst_file handle the yank function
will be leftover during paused postcopy.
Without this patch, below steps (quoted from Xiaohui) could trigger qemu src
crash:
1.Boot vm on src host
2.Boot vm on dst host
3.Enable postcopy on src&dst host
4.Load stressapptest in vm and set postcopy speed to 50M
5.Start migration from src to dst host, change into postcopy mode when migration is active.
6.When postcopy is active, down the network card(do migration via this network) on dst host.
7.Wait untill postcopy is paused on src&dst host.
8.Before up network card, recover migration on dst host, will get error like following.
9.Ignore the error of step 8, go on recovering migration on src host:
After step 9, qemu on src host will core dump after some seconds:
qemu-kvm: ../util/yank.c:107: yank_unregister_instance: Assertion `QLIST_EMPTY(&entry->yankfns)' failed.
1.sh: line 38: 44662 Aborted (core dumped)
Reported-by: Li Xiaohui <xiaohli@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210708190653.252961-2-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
When the migration fails or is canceled we wait the end of the unplug
operation to be able to plug it back. But if the unplug operation
is never finished we stop to wait and QEMU emits a warning to inform
the user.
Based-on: 20210629155007.629086-1-lvivier@redhat.com
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20210701131458.112036-1-lvivier@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
backtrace:
'0x00007ffff5f44ec2 in __ibv_dereg_mr_1_1 (mr=0x7fff1007d390) at /home/lizhijian/rdma-core/libibverbs/verbs.c:478
478 void *addr = mr->addr;
(gdb) bt
#0 0x00007ffff5f44ec2 in __ibv_dereg_mr_1_1 (mr=0x7fff1007d390) at /home/lizhijian/rdma-core/libibverbs/verbs.c:478
#1 0x0000555555891fcc in rdma_delete_block (block=<optimized out>, rdma=0x7fff38176010) at ../migration/rdma.c:691
#2 qemu_rdma_cleanup (rdma=0x7fff38176010) at ../migration/rdma.c:2365
#3 0x00005555558925b0 in qio_channel_rdma_close_rcu (rcu=0x555556b8b6c0) at ../migration/rdma.c:3073
#4 0x0000555555d652a3 in call_rcu_thread (opaque=opaque@entry=0x0) at ../util/rcu.c:281
#5 0x0000555555d5edf9 in qemu_thread_start (args=0x7fffe88bb4d0) at ../util/qemu-thread-posix.c:541
#6 0x00007ffff54c73f9 in start_thread () at /lib64/libpthread.so.0
#7 0x00007ffff53f3b03 in clone () at /lib64/libc.so.6 '
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210708144521.1959614-1-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes commit 3d0684b2ad ("ram: Update
all functions comments")
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210708162159.18045-1-olaf@aepfle.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Since the prior calls are successful, in this case a errno doesn't
indicate a real error which would just make us confused.
before:
(qemu) migrate -d rdma:192.168.22.23:8888
source_resolve_host RDMA Device opened: kernel name rxe_eth0 uverbs device name uverbs2, infiniband_verbs class device path /sys/class/infiniband_verbs/uverbs2, infiniband class device path /sys/class/infiniband/rxe_eth0, transport: (2) Ethernet
rdma_get_cm_event != EVENT_ESTABLISHED after rdma_connect: No space left on device
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210628071959.23455-1-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
If the user cancels the migration in the unplug-wait state,
QEMU will try to plug back the card and this fails because the card
is partially unplugged.
To avoid the problem, continue to wait the card unplug, but to
allow the migration to be canceled if the card never finishes to unplug
use a timeout.
Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1976852
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210629155007.629086-3-lvivier@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
The loop is used in migration_thread() and bg_migration_thread(),
so we can move it to its own function and call it from these both places.
Moreover, in migration_thread() we have a wrong state transition from
SETUP to ACTIVE while state could be WAIT_UNPLUG. This is correctly
managed in bg_migration_thread() so use this code instead.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20210629155007.629086-2-lvivier@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
It's possible qemu_start_incoming_migration() failed at any point, when it
happens we should reset postcopy_recover_triggered to false so that the user
can still retry with a saner incoming port.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210629181356.217312-3-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Starting from commit b5eea99ec2, qmp_migrate_recover() calls unregister
before calling qemu_start_incoming_migration(). I believe it wanted to mitigate
the next call to yank_register_instance(), but I think that's wrong.
Firstly, if during recover, we should keep the yank instance there, not
"quickly removing and adding it back".
Meanwhile, calling qmp_migrate_recover() twice with b5eea99ec2 will directly
crash the dest qemu (right now it can't; but it'll start to work right after
the next patch) because the 1st call of qmp_migrate_recover() will unregister
permanently when the channel failed to establish, then the 2nd call of
qmp_migrate_recover() crashes at yank_unregister_instance().
This patch fixes it by moving yank ops out of qemu_start_incoming_migration()
into qmp_migrate_incoming. For qmp_migrate_recover(), drop the unregister of
yank instance too since we keep it there during the recovery phase.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210629181356.217312-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
When testing migration, a Segmentation fault qemu core is generated.
0 error_free (err=0x1)
1 0x00007f8b862df647 in qemu_fclose (f=f@entry=0x55e06c247640)
2 0x00007f8b8516d59a in migrate_fd_cleanup (s=s@entry=0x55e06c0e1ef0)
3 0x00007f8b8516d66c in migrate_fd_cleanup_bh (opaque=0x55e06c0e1ef0)
4 0x00007f8b8626a47f in aio_bh_poll (ctx=ctx@entry=0x55e06b5a16d0)
5 0x00007f8b8626e71f in aio_dispatch (ctx=0x55e06b5a16d0)
6 0x00007f8b8626a33d in aio_ctx_dispatch (source=<optimized out>, callback=<optimized out>, user_data=<optimized out>)
7 0x00007f8b866bdba4 in g_main_context_dispatch ()
8 0x00007f8b8626cde9 in glib_pollfds_poll ()
9 0x00007f8b8626ce62 in os_host_main_loop_wait (timeout=<optimized out>)
10 0x00007f8b8626cffd in main_loop_wait (nonblocking=nonblocking@entry=0)
11 0x00007f8b862ef01f in main_loop ()
Using gdb print the struct QEMUFile f = {
...,
iovcnt = 65, last_error = 21984,
last_error_obj = 0x1, shutdown = true
}
Well iovcnt is overflow, because the max size of MAX_IOV_SIZE is 64.
struct QEMUFile {
...;
struct iovec iov[MAX_IOV_SIZE];
unsigned int iovcnt;
int last_error;
Error *last_error_obj;
bool shutdown;
};
iovcnt and last_error is overwrited by add_to_iovec().
Right now, add_to_iovec() increase iovcnt before check the limit.
And it seems that add_to_iovec() assumes that iovcnt will set to zero
in qemu_fflush(). But qemu_fflush() will directly return when f->shutdown
is true.
The situation may occur when libvirtd restart during migration, after
f->shutdown is set, before calling qemu_file_set_error() in
qemu_file_shutdown().
So the safiest way is checking the iovcnt before increasing it.
Signed-off-by: Feng Lin <linfeng23@huawei.com>
Message-Id: <20210625062138.1899-1-linfeng23@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fix typo in 'writeable' which is actually misnamed 'writable'
Avoid accessing QCryptoTLSCreds internals by using
the qcrypto_tls_creds_check_endpoint() helper.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Let's introduce RAM_NORESERVE, allowing mmap'ing with MAP_NORESERVE. The
new flag has the following semantics:
"
RAM is mmap-ed with MAP_NORESERVE. When set, reserving swap space (or huge
pages if applicable) is skipped: will bail out if not supported. When not
set, the OS will do the reservation, if supported for the memory type.
"
Allow passing it into:
- memory_region_init_ram_nomigrate()
- memory_region_init_resizeable_ram()
- memory_region_init_ram_from_file()
... and teach qemu_ram_mmap() and qemu_anon_ram_alloc() about the flag.
Bail out if the flag is not supported, which is the case right now for
both, POSIX and win32. We will add Linux support next and allow specifying
RAM_NORESERVE via memory backends.
The target use case is virtio-mem, which dynamically exposes memory
inside a large, sparse memory area to the VM.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com> for memory backend and machine core
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210510114328.21835-9-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The GDateTime APIs provided by GLib avoid portability pitfalls, such
as some platforms where 'struct timeval.tv_sec' field is still 'long'
instead of 'time_t'. When combined with automatic cleanup, GDateTime
often results in simpler code too.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This is a critical failure scenario for migration that is hard to
diagnose from existing probes. Most likely it is caused by an error
from bdrv_flush(), but we're not logging the errno anywhere, hence
this new probe.
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
We can detect disk migration in migrate_prepare, if disk migration
is enabled in COLO mode, we can directly report an error.and there
is no need to disable block migration at every checkpoint.
Signed-off-by: Lei Rao <lei.rao@intel.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Tested-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Jason Wang <jasowang@redhat.com>
These two commands are missing when adding the QMP sister commands.
Add them, so developers can play with them easier.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Message-Id: <4cc0039fc3ad6145136770cf3b0f056c09a2910b.1623027729.git.huangy81@chinatelecom.cn>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
introduce optional sample-pages argument in calc-dirty-rate,
making sample page count per GB configurable so that more
accurate dirtyrate can be calculated.
Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Message-Id: <3103453a3b2796f929269c99a6ad81a9a7f1f405.1623027729.git.huangy81@chinatelecom.cn>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Wrapped a couple of long lines
Delay closing the listener until the cleanup hook at the end; mptcp
needs the listener to stay open while the other paths come in.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210421112834.107651-5-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Add a cleanup hook for incoming migration that gets called
at the end as a way for a transport to allow cleanup.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210421112834.107651-4-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210602023506.3821293-1-lizhijian@cn.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
After yank feature was introduced in migration, whenever migration
is started using TLS, the following error happens in both source and
destination hosts:
(qemu) qemu-kvm: ../util/yank.c:107: yank_unregister_instance:
Assertion `QLIST_EMPTY(&entry->yankfns)' failed.
This happens because of a missing yank_unregister_function() when using
qio-channel-tls.
Fix this by also allowing TYPE_QIO_CHANNEL_TLS object type to perform
yank_unregister_function() in channel_close() and multifd_load_cleanup().
Also, inside migration_channel_connect() and
migration_channel_process_incoming() move yank_register_function() so
it only runs once on a TLS migration.
Fixes: b5eea99ec2 ("migration: Add yank feature", 2021-01-13)
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1964326
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Changes since v2:
- Dropped all references to ioc->master
- yank_register_function() and yank_unregister_function() now only run
once in a TLS migration.
Changes since v1:
- Cast p->c to QIOChannelTLS into multifd_load_cleanup()
Message-Id: <20210601054030.1153249-1-leobras.c@gmail.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Commit e50caf4a5c ("tracing: convert documentation to rST")
converted docs/devel/tracing.txt to docs/devel/tracing.rst.
We still have several references to the old file, so let's fix them
with the following command:
sed -i s/tracing.txt/tracing.rst/ $(git grep -l docs/devel/tracing.txt)
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210517151702.109066-2-sgarzare@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Fixes for a loadvm regression from Kevin,
some virtiofsd cleanups from Vivek and Mahmoud, and
some RDMA migration fixups from Li.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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Merge remote-tracking branch 'remotes/dgilbert/tags/pull-migration-20210526a' into staging
Virtiofs, migration and hmp pull 2021-05-26
Fixes for a loadvm regression from Kevin,
some virtiofsd cleanups from Vivek and Mahmoud, and
some RDMA migration fixups from Li.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
# gpg: Signature made Wed 26 May 2021 18:43:30 BST
# gpg: using RSA key 45F5C71B4A0CB7FB977A9FA90516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>" [full]
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A 9FA9 0516 331E BC5B FDE7
* remotes/dgilbert/tags/pull-migration-20210526a:
migration/rdma: source: poll cm_event from return path
migration/rdma: destination: create the return patch after the first accept
migration/rdma: Fix rdma_addrinfo res leaks
migration/rdma: cleanup rdma in rdma_start_incoming_migration error path
migration/rdma: Fix cm_event used before being initialized
tools/virtiofsd/fuse_opt.c: Replaced a malloc with GLib's g_try_malloc
tools/virtiofsd/buffer.c: replaced a calloc call with GLib's g_try_new0
virtiofsd: Set req->reply_sent right after sending reply
virtiofsd: Check EOF before short read
virtiofsd: Simplify skip byte logic
virtiofsd: get rid of in_sg_left variable
virtiofsd: Use iov_discard_front() to skip bytes
virtiofsd: Get rid of unreachable code in read
virtiofsd: Check for EINTR in preadv() and retry
hmp: Fix loadvm to resume the VM on success instead of failure
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
source side always blocks if postcopy is only enabled at source side.
users are not able to cancel this migration in this case.
Let source side have chance to cancel this migration
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210525080552.28259-4-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Typo fix
destination side:
$ build/qemu-system-x86_64 -enable-kvm -netdev tap,id=hn0,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown -device e1000,netdev=hn0,mac=50:52:54:00:11:22 -boot c -drive if=none,file=./Fedora-rdma-server-migration.qcow2,id=drive-virtio-disk0 -device virtio-blk-pci,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,id=virtio-disk0 -m 2048 -smp 2 -device piix3-usb-uhci -device usb-tablet -monitor stdio -vga qxl -spice streaming-video=filter,port=5902,disable-ticketing -incoming rdma:192.168.1.10:8888
(qemu) migrate_set_capability postcopy-ram on
(qemu)
dest_init RDMA Device opened: kernel name rocep1s0f0 uverbs device name uverbs0, infiniband_verbs class device path /sys/class/infiniband_verbs/uverbs0, infiniband class device path /sys/class/infiniband/rocep1s0f0, transport: (2) Ethernet
Segmentation fault (core dumped)
(gdb) bt
#0 qemu_rdma_accept (rdma=0x0) at ../migration/rdma.c:3272
#1 rdma_accept_incoming_migration (opaque=0x0) at ../migration/rdma.c:3986
#2 0x0000563c9e51f02a in aio_dispatch_handler
(ctx=ctx@entry=0x563ca0606010, node=0x563ca12b2150) at ../util/aio-posix.c:329
#3 0x0000563c9e51f752 in aio_dispatch_handlers (ctx=0x563ca0606010) at ../util/aio-posix.c:372
#4 aio_dispatch (ctx=0x563ca0606010) at ../util/aio-posix.c:382
#5 0x0000563c9e4f4d9e in aio_ctx_dispatch (source=<optimized out>, callback=<optimized out>, user_data=<optimized out>) at ../util/async.c:306
#6 0x00007fe96ef3fa9f in g_main_context_dispatch () at /lib64/libglib-2.0.so.0
#7 0x0000563c9e4ffeb8 in glib_pollfds_poll () at ../util/main-loop.c:231
#8 os_host_main_loop_wait (timeout=12188789) at ../util/main-loop.c:254
#9 main_loop_wait (nonblocking=nonblocking@entry=0) at ../util/main-loop.c:530
#10 0x0000563c9e3c7211 in qemu_main_loop () at ../softmmu/runstate.c:725
#11 0x0000563c9dfd46fe in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at ../softmmu/main.c:50
The rdma return path will not be created when qemu incoming is starting
since migrate_copy() is false at that moment, then a NULL return path
rdma was referenced if the user enabled postcopy later.
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210525080552.28259-3-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
rdma_freeaddrinfo() is the reverse operation of rdma_getaddrinfo()
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210525080552.28259-2-lizhijian@cn.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
the error path after calling qemu_rdma_dest_init() should do rdma cleanup
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210520081148.17001-1-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
A segmentation fault was triggered when i try to abort a postcopy + rdma
migration.
since rdma_ack_cm_event releases a uninitialized cm_event in these case.
like below:
2496 ret = rdma_get_cm_event(rdma->channel, &cm_event);
2497 if (ret) {
2498 perror("rdma_get_cm_event after rdma_connect");
2499 ERROR(errp, "connecting to destination!");
2500 rdma_ack_cm_event(cm_event); <<<< cause segmentation fault
2501 goto err_rdma_source_connect;
2502 }
Refer to the rdma_get_cm_event() code, cm_event will be
updated/changed only if rdma_get_cm_event() returns 0. So it's okey to
remove the ack in error patch.
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210519064740.10828-1-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
The replication.h file is included from migration/colo.c and tests/unit/test-replication.c,
so it should be in include/.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The CONFIG_VFIO switch only works in target specific code. Since
migration/migration.c is common code, the #ifdef does not have
the intended behavior here. Move the related code to a separate
file now which gets compiled via specific_ss instead.
Fixes: 3710586caa ("qapi: Add VFIO devices migration stats in Migration stats")
Message-Id: <20210414112004.943383-3-thuth@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
We never read or write beyond the used_length of memory blocks when
migrating. Make this clearer by using offset_in_ramblock() consistently.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-11-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We actually want to print the used_length, against which we check.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-10-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Resizing while migrating is dangerous and does not work as expected.
The whole migration code works with the usable_length of a ram block and
does not expect this value to change at random points in time.
In the case of postcopy, relying on used_length is racy as soon as the
guest is running. Also, when used_length changes we might leave the
uffd handler registered for some memory regions, reject valid pages
when migrating and fail when sending the recv bitmap to the source.
Resizing can be trigger *after* (but not during) a reset in
ACPI code by the guest
- hw/arm/virt-acpi-build.c:acpi_ram_update()
- hw/i386/acpi-build.c:acpi_ram_update()
Let's remember the original used_length in a separate variable and
use it in relevant postcopy code. Make sure to update it when we resize
during precopy, when synchronizing the RAM block sizes with the source.
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-9-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Add two new helper functions. This will come in come handy once we want to
handle ram block resizes while postcopy is active.
Note that ram_block_from_stream() will already print proper errors.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-8-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
dgilbert: Added brackets in host_page_from_ram_block_offset
to cause uintptr_t to cast the sum, to fix armhf-cross build
In case we grow our RAM after ram_postcopy_incoming_init() (e.g., when
synchronizing the RAM block state with the migration source), the resized
part would not get discarded. Let's perform that when being notified
about a resize while postcopy has been advised, but is not listening
yet. With precopy, the process is as following:
1. VM created
- RAM blocks are created
2. Incomming migration started
- Postcopy is advised
- All pages in RAM blocks are discarded
3. Precopy starts
- RAM blocks are resized to match the size on the migration source.
- RAM pages from precopy stream are loaded
- Uffd handler is registered, postcopy starts listening
4. Guest started, postcopy running
- Pagefaults get resolved, pages get placed
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-7-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Resizing while migrating is dangerous and does not work as expected.
The whole migration code works on the usable_length of ram blocks and does
not expect this to change at random points in time.
In the case of precopy, the ram block size must not change on the source,
after syncing the RAM block list in ram_save_setup(), so as long as the
guest is still running on the source.
Resizing can be trigger *after* (but not during) a reset in
ACPI code by the guest
- hw/arm/virt-acpi-build.c:acpi_ram_update()
- hw/i386/acpi-build.c:acpi_ram_update()
Use the ram block notifier to get notified about resizes. Let's simply
cancel migration and indicate the reason. We'll continue running on the
source. No harm done.
Update the documentation. Postcopy will be handled separately.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-5-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Manual merge
Result @blocked is redundant. Unfortunately, we realized this too
close to the release to risk dropping it, so we deprecated it
instead, in commit e11ce6c06.
Since it was deprecated from the start, we can delete it without
the customary grace period. Do so.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210429140424.2802929-1-armbru@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Starting from pss->page, ram_save_host_page() will check every page
and send the dirty pages up to the end of the current host page or
the boundary of used_length of the block. If the host page size is
a huge page, the step "check" will take a lot of time.
It will improve performance to use migration_bitmap_find_dirty().
Tested on Kunpeng 920; VM parameters: 1U 4G (page size 1G)
The time of ram_save_host_page() in the last round of ram saving:
before optimize: 9250us after optimize: 34us
Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210316125716.1243-3-jiangkunkun@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
When the host page is a huge page and something is sent in the
current iteration, migration_rate_limit() should be executed.
If not, it can be omitted.
Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
Reviewed-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210316125716.1243-2-jiangkunkun@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
The bulk stage is kind of weird: migration_bitmap_find_dirty() will
indicate a dirty page, however, ram_save_host_page() will never save it, as
migration_bitmap_clear_dirty() detects that it is not dirty.
We already fill the bitmap in ram_list_init_bitmaps() with ones, marking
everything dirty - it didn't used to be that way, which is why we needed
an explicit first bulk stage.
Let's simplify: make the bitmap the single source of thuth. Explicitly
handle the "xbzrle_enabled after first round" case.
Regarding XBZRLE (implicitly handled via "ram_bulk_stage = false" right
now), there is now a slight change in behavior:
- Colo: When starting, it will be disabled (was implicitly enabled)
until the first round actually finishes.
- Free page hinting: When starting, XBZRLE will be disabled (was implicitly
enabled) until the first round actually finished.
- Snapshots: When starting, XBZRLE will be disabled. We essentially only
do a single run, so I guess it will never actually get disabled.
Postcopy seems to indirectly disable it in ram_save_page(), so there
shouldn't be really any change.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210216105039.40680-1-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Stop including cpu.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-4-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Stop including sysemu/sysemu.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-2-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Rename 'bs' to commonly used 'block' in migration/ram.c background
snapshot code.
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-5-andrey.gruzdev@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This commit solves the issue with userfault_fd WP feature that
background snapshot is based on. For any never poluated or discarded
memory page, the UFFDIO_WRITEPROTECT ioctl() would skip updating
PTE for that page, thereby loosing WP setting for it.
So we need to pre-fault pages for each RAM block to be protected
before making a userfault_fd wr-protect ioctl().
Fixes: 278e2f551a (migration: support
UFFD write fault processing in ram_save_iterate())
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-4-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
dgilbert:
Bodged ifdef __linux__ on ram_write_tracking_prepare, should really
go in a stub
The same thing as for incoming postcopy - we cannot deal with concurrent
RAM discards when using background snapshot feature in outgoing migration.
Fixes: 8518278a6a (migration: implementation
of background snapshot thread)
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-3-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
