Pull virtio,vhost,vdpa updates from Michael Tsirkin:
- Doorbell remapping for ifcvf, mlx5
- virtio_vdpa support for mlx5
- Validate device input in several drivers (for SEV and friends)
- ZONE_MOVABLE aware handling in virtio-mem
- Misc fixes, cleanups
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (48 commits)
virtio-mem: prioritize unplug from ZONE_MOVABLE in Big Block Mode
virtio-mem: simplify high-level unplug handling in Big Block Mode
virtio-mem: prioritize unplug from ZONE_MOVABLE in Sub Block Mode
virtio-mem: simplify high-level unplug handling in Sub Block Mode
virtio-mem: simplify high-level plug handling in Sub Block Mode
virtio-mem: use page_zonenum() in virtio_mem_fake_offline()
virtio-mem: don't read big block size in Sub Block Mode
virtio/vdpa: clear the virtqueue state during probe
vp_vdpa: allow set vq state to initial state after reset
virtio-pci library: introduce vp_modern_get_driver_features()
vdpa: support packed virtqueue for set/get_vq_state()
virtio-ring: store DMA metadata in desc_extra for split virtqueue
virtio: use err label in __vring_new_virtqueue()
virtio_ring: introduce virtqueue_desc_add_split()
virtio_ring: secure handling of mapping errors
virtio-ring: factor out desc_extra allocation
virtio_ring: rename vring_desc_extra_packed
virtio-ring: maintain next in extra state for packed virtqueue
vdpa/mlx5: Clear vq ready indication upon device reset
vdpa/mlx5: Add support for doorbell bypassing
...
Let's handle unplug in Big Block Mode similar to Sub Block Mode --
prioritize memory blocks onlined to ZONE_MOVABLE.
We won't care further about big blocks with mixed zones, as it's
rather a corner case that won't matter in practice.
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-8-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Let's simplify high-level big block selection when unplugging in
Big Block Mode.
Combine handling of offline and online blocks. We can get rid of
virtio_mem_bbm_bb_is_offline() and simply use
virtio_mem_bbm_offline_remove_and_unplug_bb(), as that already tolerates
offline parts.
We can race with concurrent onlining/offlining either way, so we don;t
have to be super correct by failing if an offline big block we'd like to
unplug just got (partially) onlined.
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-7-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Until now, memory provided by a single virtio-mem device was usually
either onlined completely to ZONE_MOVABLE (online_movable) or to
ZONE_NORMAL (online_kernel); however, that will change in the future.
There are two reasons why we want to track to which zone a memory blocks
belongs to and prioritize ZONE_MOVABLE blocks:
1) Memory managed by ZONE_MOVABLE can more likely get unplugged, therefore,
resulting in a faster memory hotunplug process. Further, we can more
reliably unplug and remove complete memory blocks, removing metadata
allocated for the whole memory block.
2) We want to avoid corner cases where unplugging with the current scheme
(highest to lowest address) could result in accidential zone imbalances,
whereby we remove too much ZONE_NORMAL memory for ZONE_MOVABLE memory
of the same device.
Let's track the zone via memory block states and try unplug from
ZONE_MOVABLE first. Rename VIRTIO_MEM_SBM_MB_ONLINE* to
VIRTIO_MEM_SBM_MB_KERNEL* to avoid even longer state names.
In commit 27f852795a ("virtio-mem: don't special-case ZONE_MOVABLE"),
we removed slightly similar tracking for fully plugged memory blocks to
support unplugging from ZONE_MOVABLE at all -- as we didn't allow partially
plugged memory blocks in ZONE_MOVABLE before that. That commit already
mentioned "In the future, we might want to remember the zone again and use
the information when (un)plugging memory."
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-6-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Let's simplify by introducing a new virtio_mem_sbm_unplug_any_sb(),
similar to virtio_mem_sbm_plug_any_sb(), to simplify high-level memory
block selection when unplugging in Sub Block Mode.
Rename existing virtio_mem_sbm_unplug_any_sb() to
virtio_mem_sbm_unplug_any_sb_raw().
The only change is that we now temporarily unlock the hotplug mutex around
cond_resched() when processing offline memory blocks, which doesn't
make a real difference as we already have to temporarily unlock in
virtio_mem_sbm_unplug_any_sb_offline() when removing a memory block.
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-5-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Let's simplify high-level memory block selection when plugging in Sub
Block Mode.
No need for two separate loops when selecting memory blocks for plugging
memory. Avoid passing the "online" state by simply obtaining the state
in virtio_mem_sbm_plug_any_sb().
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-4-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We are reading a Big Block Mode value while in Sub Block Mode
when initializing. Fortunately, vm->bbm.bb_size maps to some counter
in the vm->sbm.mb_count array, which is 0 at that point in time.
No harm done; still, this was unintended and is not future-proof.
Fixes: 4ba50cd335 ("virtio-mem: Big Block Mode (BBM) memory hotplug")
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20210602185720.31821-2-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Merge more updates from Andrew Morton:
"118 patches:
- The rest of MM.
Includes kfence - another runtime memory validator. Not as thorough
as KASAN, but it has unmeasurable overhead and is intended to be
usable in production builds.
- Everything else
Subsystems affected by this patch series: alpha, procfs, sysctl,
misc, core-kernel, MAINTAINERS, lib, bitops, checkpatch, init,
coredump, seq_file, gdb, ubsan, initramfs, and mm (thp, cma,
vmstat, memory-hotplug, mlock, rmap, zswap, zsmalloc, cleanups,
kfence, kasan2, and pagemap2)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
MIPS: make userspace mapping young by default
initramfs: panic with memory information
ubsan: remove overflow checks
kgdb: fix to kill breakpoints on initmem after boot
scripts/gdb: fix list_for_each
x86: fix seq_file iteration for pat/memtype.c
seq_file: document how per-entry resources are managed.
fs/coredump: use kmap_local_page()
init/Kconfig: fix a typo in CC_VERSION_TEXT help text
init: clean up early_param_on_off() macro
init/version.c: remove Version_<LINUX_VERSION_CODE> symbol
checkpatch: do not apply "initialise globals to 0" check to BPF progs
checkpatch: don't warn about colon termination in linker scripts
checkpatch: add kmalloc_array_node to unnecessary OOM message check
checkpatch: add warning for avoiding .L prefix symbols in assembly files
checkpatch: improve TYPECAST_INT_CONSTANT test message
checkpatch: prefer ftrace over function entry/exit printks
checkpatch: trivial style fixes
checkpatch: ignore warning designated initializers using NR_CPUS
checkpatch: improve blank line after declaration test
...
Let's try to unplug completely offline big blocks first. Then, (if
enabled via unplug_offline) try to offline and remove whole big blocks.
No locking necessary - we can deal with concurrent onlining/offlining
just fine.
Note1: This is sub-optimal and might be dangerous in some environments: we
could end up in an infinite loop when offlining (e.g., long-term pinnings),
similar as with DIMMs. We'll introduce safe memory hotunplug via
fake-offlining next, and use this basic mode only when explicitly enabled.
Note2: Without ZONE_MOVABLE, memory unplug will be extremely unreliable
with bigger block sizes.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-29-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Currently, we do not support device block sizes that exceed the Linux
memory block size. For example, having a device block size of 1 GiB (e.g.,
gigantic pages in the hypervisor) won't work with 128 MiB Linux memory
blocks.
Let's implement Big Block Mode (BBM), whereby we add/remove at least
one Linux memory block at a time. With a 1 GiB device block size, a Big
Block (BB) will cover 8 Linux memory blocks.
We'll keep registering the online_page_callback machinery, it will be used
for safe memory hotunplug in BBM next.
Note: BBM is properly prepared for variable-sized Linux memory
blocks that we might see in the future. So we won't care how many Linux
memory blocks a big block actually spans, and how the memory notifier is
called.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-26-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Let's use wrappers for the low-level functions that dev_dbg/dev_warn
and work on addr + size, such that we can reuse them for adding/removing
in other granularity.
We only warn when adding memory failed, because that's something to pay
attention to. We won't warn when removing failed, we'll reuse that in
racy context soon (and we do have proper BUG_ON() statements in the
current cases where it must never happen).
Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-25-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We don't want to add too much memory when it's not getting onlined
immediately, to avoid running OOM. Generalize the handling, to avoid
making use of memory block states. Use a threshold of 1 GiB for now.
Properly adjust the offline size when adding/removing memory. As we are
not always protected by a lock when touching the offline size, use an
atomic64_t. We don't care about races (e.g., someone offlining memory
while we are adding more), only about consistent values.
(1 GiB needs a memmap of ~16MiB - which sounds reasonable even for
setups with little boot memory and (possibly) one virtio-mem device per
node)
We don't want to retrigger when onlining is caused immediately by our
action (e.g., adding memory which immediately gets onlined), so use a
flag to indicate if the workqueue is active and use that as an
indicator whether to trigger a retry. This will also be especially relevant
for Big Block Mode (BBM), whereby we might re-online memory in case
offlining of another memory block failed.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-17-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Let's trigger from offlining code only when we're not allowed to unplug
online memory. Handle the other case (memmap possibly freeing up another
memory block) when actually removing memory. We now also properly handle
the case when removing already offline memory blocks via
virtio_mem_mb_remove(). When removing via virtio_mem_remove(), when
unloading the driver, virtio_mem_retry() is a NOP and safe to use.
While at it, move retry handling when offlining out of
virtio_mem_notify_offline(), to share it with Big Block Mode (BBM)
soon.
This is a preparation for Big Block Mode (BBM), whereby we can see some
temporary offlining of memory blocks without actually making progress.
Imagine you have a Big Block that spans to Linux memory blocks. Assume
the first Linux memory blocks has no unmovable data on it. When we would
call offline_and_remove_memory() on the big block, we would
1. Try to offline the first block. Works, notifiers triggered.
virtio_mem_retry() called.
2. Try to offline the second block. Does not work.
3. Re-online first block.
4. Exit to main loop, exit workqueue.
5. Retry immediately (due to virtio_mem_retry()), go to 1.
The result are endless retries.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-16-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Pull virtio updates from Michael Tsirkin:
"vhost, vdpa, and virtio cleanups and fixes
A very quiet cycle, no new features"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
MAINTAINERS: add URL for virtio-mem
vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call
vringh: fix __vringh_iov() when riov and wiov are different
vdpa/mlx5: Setup driver only if VIRTIO_CONFIG_S_DRIVER_OK
s390: virtio: PV needs VIRTIO I/O device protection
virtio: let arch advertise guest's memory access restrictions
vhost_vdpa: Fix duplicate included kernel.h
vhost: reduce stack usage in log_used
virtio-mem: Constify mem_id_table
virtio_input: Constify id_table
virtio-balloon: Constify id_table
vdpa/mlx5: Fix failure to bring link up
vdpa/mlx5: Make use of a specific 16 bit endianness API
virtio-mem adds memory in memory block granularity, to be able to remove
it in the same granularity again later, and to grow slowly on demand.
This, however, results in quite a lot of resources when adding a lot of
memory. Resources are effectively stored in a list-based tree. Having a
lot of resources not only wastes memory, it also makes traversing that
tree more expensive, and makes /proc/iomem explode in size (e.g.,
requiring kexec-tools to manually merge resources later when e.g., trying
to create a kdump header).
Before this patch, we get (/proc/iomem) when hotplugging 2G via virtio-mem
on x86-64:
[...]
100000000-13fffffff : System RAM
140000000-33fffffff : virtio0
140000000-147ffffff : System RAM (virtio_mem)
148000000-14fffffff : System RAM (virtio_mem)
150000000-157ffffff : System RAM (virtio_mem)
158000000-15fffffff : System RAM (virtio_mem)
160000000-167ffffff : System RAM (virtio_mem)
168000000-16fffffff : System RAM (virtio_mem)
170000000-177ffffff : System RAM (virtio_mem)
178000000-17fffffff : System RAM (virtio_mem)
180000000-187ffffff : System RAM (virtio_mem)
188000000-18fffffff : System RAM (virtio_mem)
190000000-197ffffff : System RAM (virtio_mem)
198000000-19fffffff : System RAM (virtio_mem)
1a0000000-1a7ffffff : System RAM (virtio_mem)
1a8000000-1afffffff : System RAM (virtio_mem)
1b0000000-1b7ffffff : System RAM (virtio_mem)
1b8000000-1bfffffff : System RAM (virtio_mem)
3280000000-32ffffffff : PCI Bus 0000:00
With this patch, we get (/proc/iomem):
[...]
fffc0000-ffffffff : Reserved
100000000-13fffffff : System RAM
140000000-33fffffff : virtio0
140000000-1bfffffff : System RAM (virtio_mem)
3280000000-32ffffffff : PCI Bus 0000:00
Of course, with more hotplugged memory, it gets worse. When unplugging
memory blocks again, try_remove_memory() (via offline_and_remove_memory())
will properly split the resource up again.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Grall <julien@xen.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Leonardo Bras <leobras.c@gmail.com>
Cc: Libor Pechacek <lpechacek@suse.cz>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Lynch <nathanl@linux.ibm.com>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Roger Pau Monné <roger.pau@citrix.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Wei Liu <wei.liu@kernel.org>
Link: https://lkml.kernel.org/r/20200911103459.10306-7-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather
unclear, which is why we special-cased ZONE_MOVABLE such that partially
plugged blocks would never end up in ZONE_MOVABLE.
Now that the semantics are much clearer (and will be documented in a
follow-up patch including the new virtio-mem behavior), let's allow to
online partially plugged memory blocks to ZONE_MOVABLE and also consider
memory blocks that were onlined to ZONE_MOVABLE when unplugging memory.
While unplugged memory pages are, in general, unmovable, they can be
skipped when offlining memory.
virtio-mem only unplugs fairly big chunks (in the megabyte range) and
rather tries to shrink the memory region than randomly choosing memory.
In theory, if all other pages in the movable zone would be movable,
virtio-mem would only shrink that zone and not create any kind of
fragmentation.
In the future, we might want to remember the zone again and use the
information when (un)plugging memory. For now, let's keep it simple.
Note: Support for defragmentation is planned, to deal with fragmentation
after unplug due to memory chunks within memory blocks that could not get
unplugged before (e.g., somebody pinning pages within ZONE_MOVABLE for a
longer time).
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/20200816125333.7434-6-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
