I/O errors were reported after a successful replacement of the ploop images.
'ploop replace' did not clear 'abort' flag.
It was found that if a ploop image was revoked and then replaced using 'ploop replace', 'abort' flag was not cleared. As a result, subsequent I/O operations would fail.
ploop: potential data corruption due to a race between 'prepare_merge' and 'submit_alloc' operations.
vzstat shows incorrect per-CT scheduling latency (MLAT).
High order page allocations were made in neigh_probe() in certain cases.
High order page allocations were triggered by CRIU while restoring TCP sockets.
Network performance issues due to the usage of pfmemalloc reserves.
It was discovered that network drivers could allocate memory for the socket buffers from pfmemalloc memory reserves, even when it was unnecessary. As a result, the network packets were dropped by sk_filter_trim_cap() causing performance issues.
fuse_kio_pcs: kernel crash in process_pcs_init_reply() caused by a double free.
fuse_kio_pcs: kernel crash in kpcs_kill_requests().
skb drops due to the usage of pfmemalloc reserves were difficult to debug.
Additional diagnostics was introduced to make it easier to detect and analyze skb drops due to the usage of pfmemalloc reserves.
KVM did not update CPUID bits OSXSAVE and OSPKE in some cases.
It was discovered that CPUID bits OSXSAVE and OSPKE were not updated properly by KVM when the guest system rebooted. As a result, the guest system could crash.
The per-container limit on the network interfaces was too low for Docker in some cases.
It was discovered that Docker running inside a Virtuozzo container could hit the limit on the network interfaces (256) when it tried to start 50+ its containers. This fix allows changing that limit for the running containers and increases the default limit to 1024.
txqueuelen could not be changed via SIOCSIFTXQLEN ioctl on the host.
Kernel crash in ext4_clear_inode().
A large tarball with a lot of small files can fail to unpack inside a container if kmem limit is set.
It was found that unpacking a large tarball with a lot of small files could fail inside a container. This could happen because kmem limit was hit prematurely, while reclaimable memory was still available.
sr_mod: kernel crash in sr_block_revalidate_disk().