06 Jan, 2015
4 commits
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The reason we defer kfree until release function is because it's a
general rule for kobjects: kfree of the reference counter itself is only
legal in the release function.Previous patch didn't make this clear, document this in code.
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin -
A struct device which has just been unregistered can live on past the
point at which a driver decides to drop it's initial reference to the
kobject gained on allocation.This implies that when releasing a virtio device, we can't free a struct
virtio_device until the underlying struct device has been released,
which might not happen immediately on device_unregister().Unfortunately, this is exactly what virtio pci does:
it has an empty release callback, and frees memory immediately
after unregistering the device.This causes an easy to reproduce crash if CONFIG_DEBUG_KOBJECT_RELEASE
it enabled.To fix, free the memory only once we know the device is gone in the release
callback.Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin
Signed-off-by: Michael S. Tsirkin -
It turns out we need to add device-specific code
in release callback. Move it to virtio_pci_legacy.c.Signed-off-by: Michael S. Tsirkin
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Our code calls del_vqs multiple times, assuming
it's idempotent.commit 3ec7a77bb3089bb01032fdbd958eb5c29da58b49
virtio_pci: free up vq->priv
broke this assumption, by adding kfree there,
so multiple calls cause double free.Fix it up.
Fixes: 3ec7a77bb3089bb01032fdbd958eb5c29da58b49
Reported-by: Sasha Levin
Signed-off-by: Michael S. Tsirkin
19 Dec, 2014
1 commit
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Pull virtio fixes from Michael S Tsirkin:
"virtio 1.0 related fixesMost importantly, this fixes using virtio_pci as a module.
Further, the big virtio 1.0 conversion missed a couple of places.
This fixes them up.This isn't 100% sparse-clean yet because on many architectures
get_user triggers sparse warnings when used with __bitwise tag (when
same tag is on both pointer and value read).I posted a patchset to fix it up by adding __force on all arches that
don't already have it (many do), when that's merged these warnings
will go away"* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_pci: restore module attributes
mic/host: fix up virtio 1.0 APIs
vringh: update for virtio 1.0 APIs
vringh: 64 bit features
tools/virtio: add virtio 1.0 in vringh_test
tools/virtio: add virtio 1.0 in virtio_test
tools/virtio: enable -Werror
tools/virtio: 64 bit features
tools/virtio: fix vringh test
tools/virtio: more stubs
virtio: core support for config generation
virtio_pci: add VIRTIO_PCI_NO_LEGACY
virtio_pci: move probe to common file
virtio_pci_common.h: drop VIRTIO_PCI_NO_LEGACY
virtio_config: fix virtio_cread_bytes
virtio: set VIRTIO_CONFIG_S_FEATURES_OK on restore
18 Dec, 2014
1 commit
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Pull virtio updates from Rusty Russell:
"A balloon enhancement, and a minor race-on-module-unload theoretical
bug which doesn't merit cc: stable.All the exciting stuff went via MST this cycle"
* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
virtio_balloon: free some memory from balloon on OOM
virtio_balloon: return the amount of freed memory from leak_balloon()
virtio_blk: fix race at module removal
virtio: Fix comment typo 'CONFIG_S_FAILED'
17 Dec, 2014
1 commit
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When the virtio_pci driver was moved into virtio_pci_legacy.c the module
licence and other attributes went AWOL. This patch restores them.Signed-off-by: Herbert Xu
Signed-off-by: Michael S. Tsirkin
15 Dec, 2014
1 commit
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Pull driver core update from Greg KH:
"Here's the set of driver core patches for 3.19-rc1.They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes,
just removing a line in a structure.Other than that, a few minor driver core and debugfs changes. There
are some ath9k patches coming in through this tree that have been
acked by the wireless maintainers as they relied on the debugfs
changes.Everything has been in linux-next for a while"
* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
fs: debugfs: add forward declaration for struct device type
firmware class: Deletion of an unnecessary check before the function call "vunmap"
firmware loader: fix hung task warning dump
devcoredump: provide a one-way disable function
device: Add dev__once variants
ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
ath: use seq_file api for ath9k debugfs files
debugfs: add helper function to create device related seq_file
drivers/base: cacheinfo: remove noisy error boot message
Revert "core: platform: add warning if driver has no owner"
drivers: base: support cpu cache information interface to userspace via sysfs
drivers: base: add cpu_device_create to support per-cpu devices
topology: replace custom attribute macros with standard DEVICE_ATTR*
cpumask: factor out show_cpumap into separate helper function
driver core: Fix unbalanced device reference in drivers_probe
driver core: fix race with userland in device_add()
sysfs/kernfs: make read requests on pre-alloc files use the buffer.
sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
fs: sysfs: return EGBIG on write if offset is larger than file size
...
14 Dec, 2014
1 commit
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It turns out this make everything easier.
Signed-off-by: Michael S. Tsirkin
12 Dec, 2014
2 commits
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Legacy drivers use virtio_pci_common.h too, we should not
define VIRTIO_PCI_NO_LEGACY there.Signed-off-by: Michael S. Tsirkin
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virtio 1.0 devices require that drivers set VIRTIO_CONFIG_S_FEATURES_OK
after finalizing features.
virtio core missed doing this on restore, fix it up.Signed-off-by: Michael S. Tsirkin
Reviewed-by: Cornelia Huck
10 Dec, 2014
12 commits
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kbuild does not seem to like it when we name source
files same as the module.
Let's rename virtio_pci -> virtio_pci_common,
and get rid of #include-ing c files.Signed-off-by: Michael S. Tsirkin
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There's been a lot of changes since 2007.
List main authors, add Red Hat copyright.Signed-off-by: Michael S. Tsirkin
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Move everything dealing with legacy devices out to virtio_pci_legacy.c.
Expose common code APIs in virtio_pci.hSigned-off-by: Michael S. Tsirkin
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config vector setup is version specific, do it indirectly.
Signed-off-by: Michael S. Tsirkin
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VQ setup is mostly version-specific, add another level of indirection to
split the version-independent code out.Signed-off-by: Michael S. Tsirkin
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VQ deletion is mostly version-specific, add another level of indirection
to split the version-independent code out.Signed-off-by: Michael S. Tsirkin
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slightly reduce the amount of pointer chasing this needs to do.
More importantly, this will easily generalize to virtio 1.0.Signed-off-by: Michael S. Tsirkin
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We don't need to go from vq to vq info on
data path, so using direct vq->priv pointer for that
seems like a waste.Let's build an array of vq infos, then we can use vq->index
for that lookup.Signed-off-by: Michael S. Tsirkin
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should be
struct foo {
}not
struct foo
{
}Signed-off-by: Michael S. Tsirkin
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Use isr field instead of direct access to ioaddr.
This way generalizes easily to virtio 1.0.Signed-off-by: Michael S. Tsirkin
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legacy_only flag is now unused, drop it from core.
Signed-off-by: Michael S. Tsirkin
Acked-by: Cornelia Huck -
we have blacklisted balloon in core, no need
for a driver flag.Signed-off-by: Michael S. Tsirkin
Acked-by: Cornelia Huck
09 Dec, 2014
12 commits
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This will make it easy for transports to validate features and return
failure.Signed-off-by: Michael S. Tsirkin
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transports need to be able to detect legacy-only
devices (ATM balloon only) to use legacy path
to drive them.Add a core API to do just that.
The implementation just blacklists balloon:
not too pretty, but let's not over-engineer.Signed-off-by: Michael S. Tsirkin
Acked-by: Cornelia Huck -
Activate VIRTIO_F_VERSION_1 automatically unless legacy_only
is set.Signed-off-by: Michael S. Tsirkin
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We have no plans to support virtio 1.0 in balloon driver. Add an
explicit flag to mark it legacy only.This will be used by follow-up patches.
Signed-off-by: Michael S. Tsirkin
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virtio-blk has some legacy feature bits that modern drivers
must not negotiate, but are needed for old legacy hosts
(that e.g. don't support virtio-scsi).
Allow a separate legacy feature table for such cases.Signed-off-by: Michael S. Tsirkin
Reviewed-by: Cornelia Huck -
Now that we use u64 for bits, we can simply & them together.
Signed-off-by: Michael S. Tsirkin
Reviewed-by: David Hildenbrand
Reviewed-by: Cornelia Huck -
set FEATURES_OK as per virtio 1.0 spec
Signed-off-by: Michael S. Tsirkin
Reviewed-by: Cornelia Huck -
For virtio-1, we can theoretically have a more complex virtqueue
layout with avail and used buffers not on a contiguous memory area
with the descriptor table. For now, it's fine for a transport driver
to stay with the old layout: It needs, however, a way to access
the locations of the avail/used rings so it can register them with
the host.Reviewed-by: David Hildenbrand
Signed-off-by: Cornelia HuckSigned-off-by: Michael S. Tsirkin
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Use virtioXX_to_cpu and friends for access to
all multibyte structures in memory.Note: this is intentionally mechanical.
A follow-up patch will split long lines etc.Signed-off-by: Michael S. Tsirkin
Reviewed-by: Cornelia Huck -
At this point, no transports set any of the high 32 feature bits.
Since transports generally can't (yet) cope with such bits, add BUG_ON
checks to make sure they are not set by mistake.Based on rproc patch by Rusty.
Signed-off-by: Rusty Russell
Signed-off-by: Michael S. Tsirkin
Reviewed-by: David Hildenbrand
Reviewed-by: Cornelia Huck -
Change u32 to u64, and use BIT_ULL and 1ULL everywhere.
Note: transports are unchanged, and only set low 32 bit.
This guarantees that no transport sets e.g. VERSION_1
by mistake without proper support.Based on patch by Rusty.
Signed-off-by: Rusty Russell
Signed-off-by: Cornelia Huck
Signed-off-by: Michael S. Tsirkin
Reviewed-by: David Hildenbrand
Reviewed-by: Cornelia Huck -
It seemed like a good idea to use bitmap for features
in struct virtio_device, but it's actually a pain,
and seems to become even more painful when we get more
than 32 feature bits. Just change it to a u32 for now.Based on patch by Rusty.
Suggested-by: David Hildenbrand
Signed-off-by: Rusty Russell
Signed-off-by: Cornelia Huck
Signed-off-by: Michael S. Tsirkin
Reviewed-by: Cornelia Huck
11 Nov, 2014
2 commits
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Excessive virtio_balloon inflation can cause invocation of OOM-killer,
when Linux is under severe memory pressure. Various mechanisms are
responsible for correct virtio_balloon memory management. Nevertheless
it is often the case that these control tools does not have enough time
to react on fast changing memory load. As a result OS runs out of memory
and invokes OOM-killer. The balancing of memory by use of the virtio
balloon should not cause the termination of processes while there are
pages in the balloon. Now there is no way for virtio balloon driver to
free some memory at the last moment before some process will be get
killed by OOM-killer.This does not provide a security breach as balloon itself is running
inside guest OS and is working in the cooperation with the host. Thus
some improvements from guest side should be considered as normal.To solve the problem, introduce a virtio_balloon callback which is
expected to be called from the oom notifier call chain in out_of_memory()
function. If virtio balloon could release some memory, it will make
the system to return and retry the allocation that forced the out of
memory killer to run.Allocate virtio feature bit for this: it is not set by default,
the the guest will not deflate virtio balloon on OOM without explicit
permission from host.Signed-off-by: Raushaniya Maksudova
Signed-off-by: Denis V. Lunev
Acked-by: Michael S. Tsirkin
Signed-off-by: Rusty Russell -
This value would be useful in the next patch to provide the amount of
the freed memory for OOM killer.Signed-off-by: Raushaniya Maksudova
Signed-off-by: Denis V. Lunev
CC: Rusty Russell
CC: Michael S. Tsirkin
Signed-off-by: Rusty Russell
20 Oct, 2014
1 commit
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A platform_driver does not need to set an owner, it will be populated by the
driver core.Signed-off-by: Wolfram Sang
19 Oct, 2014
1 commit
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Pull virtio updates from Rusty Russell:
"One cc: stable commit, the rest are a series of minor cleanups which
have been sitting in MST's tree during my vacation. I changed a
function name and made one trivial change, then they spent two days in
linux-next"* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (25 commits)
virtio-rng: refactor probe error handling
virtio_scsi: drop scan callback
virtio_balloon: enable VQs early on restore
virtio_scsi: fix race on device removal
virito_scsi: use freezable WQ for events
virtio_net: enable VQs early on restore
virtio_console: enable VQs early on restore
virtio_scsi: enable VQs early on restore
virtio_blk: enable VQs early on restore
virtio_scsi: move kick event out from virtscsi_init
virtio_net: fix use after free on allocation failure
9p/trans_virtio: enable VQs early
virtio_console: enable VQs early
virtio_blk: enable VQs early
virtio_net: enable VQs early
virtio: add API to enable VQs early
virtio_net: minor cleanup
virtio-net: drop config_mutex
virtio_net: drop config_enable
virtio-blk: drop config_mutex
...
15 Oct, 2014
1 commit
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virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after resume returns, virtio balloon
violated this rule by adding bufs, which causes the VQ to be used
directly within restore.To fix, call virtio_device_ready before using VQ.
Signed-off-by: Michael S. Tsirkin
Signed-off-by: Rusty Russell