Commit Graph

75174 Commits

Author SHA1 Message Date
Eric Auger
cfb42188b2 virtio-iommu: Implement attach/detach command
This patch implements the endpoint attach/detach to/from
a domain.

Domain and endpoint internal datatypes are introduced.
Both are stored in RB trees. The domain owns a list of
endpoints attached to it. Also helpers to get/put
end points and domains are introduced.

As for the IOMMU memory regions, a callback is called on
PCI bus enumeration that initializes for a given device
on the bus hierarchy an IOMMU memory region. The PCI bus
hierarchy is stored locally in IOMMUPciBus and IOMMUDevice
objects.

At the time of the enumeration, the bus number may not be
computed yet.

So operations that will need to retrieve the IOMMUdevice
and its IOMMU memory region from the bus number and devfn,
once the bus number is garanteed to be frozen, use an array
of IOMMUPciBus, lazily populated.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>

Message-Id: <20200214132745.23392-4-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-27 03:46:10 -05:00
Eric Auger
5442b854ea virtio-iommu: Decode the command payload
This patch adds the command payload decoding and
introduces the functions that will do the actual
command handling. Those functions are not yet implemented.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>

Message-Id: <20200214132745.23392-3-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-27 03:46:10 -05:00
Eric Auger
22c37a10f3 virtio-iommu: Add skeleton
This patchs adds the skeleton for the virtio-iommu device.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>

Message-Id: <20200214132745.23392-2-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-27 03:46:10 -05:00
Stefan Hajnoczi
abdd16f468 virtio: gracefully handle invalid region caches
The virtqueue code sets up MemoryRegionCaches to access the virtqueue
guest RAM data structures.  The code currently assumes that
VRingMemoryRegionCaches is initialized before device emulation code
accesses the virtqueue.  An assertion will fail in
vring_get_region_caches() when this is not true.  Device fuzzing found a
case where this assumption is false (see below).

Virtqueue guest RAM addresses can also be changed from a vCPU thread
while an IOThread is accessing the virtqueue.  This breaks the same
assumption but this time the caches could become invalid partway through
the virtqueue code.  The code fetches the caches RCU pointer multiple
times so we will need to validate the pointer every time it is fetched.

Add checks each time we call vring_get_region_caches() and treat invalid
caches as a nop: memory stores are ignored and memory reads return 0.

The fuzz test failure is as follows:

  $ qemu -M pc -device virtio-blk-pci,id=drv0,drive=drive0,addr=4.0 \
         -drive if=none,id=drive0,file=null-co://,format=raw,auto-read-only=off \
         -drive if=none,id=drive1,file=null-co://,file.read-zeroes=on,format=raw \
         -display none \
         -qtest stdio
  endianness
  outl 0xcf8 0x80002020
  outl 0xcfc 0xe0000000
  outl 0xcf8 0x80002004
  outw 0xcfc 0x7
  write 0xe0000000 0x24 0x00ffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffab5cffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffabffffffab0000000001
  inb 0x4
  writew 0xe000001c 0x1
  write 0xe0000014 0x1 0x0d

The following error message is produced:

  qemu-system-x86_64: /home/stefanha/qemu/hw/virtio/virtio.c:286: vring_get_region_caches: Assertion `caches != NULL' failed.

The backtrace looks like this:

  #0  0x00007ffff5520625 in raise () at /lib64/libc.so.6
  #1  0x00007ffff55098d9 in abort () at /lib64/libc.so.6
  #2  0x00007ffff55097a9 in _nl_load_domain.cold () at /lib64/libc.so.6
  #3  0x00007ffff5518a66 in annobin_assert.c_end () at /lib64/libc.so.6
  #4  0x00005555559073da in vring_get_region_caches (vq=<optimized out>) at qemu/hw/virtio/virtio.c:286
  #5  vring_get_region_caches (vq=<optimized out>) at qemu/hw/virtio/virtio.c:283
  #6  0x000055555590818d in vring_used_flags_set_bit (mask=1, vq=0x5555575ceea0) at qemu/hw/virtio/virtio.c:398
  #7  virtio_queue_split_set_notification (enable=0, vq=0x5555575ceea0) at qemu/hw/virtio/virtio.c:398
  #8  virtio_queue_set_notification (vq=vq@entry=0x5555575ceea0, enable=enable@entry=0) at qemu/hw/virtio/virtio.c:451
  #9  0x0000555555908512 in virtio_queue_set_notification (vq=vq@entry=0x5555575ceea0, enable=enable@entry=0) at qemu/hw/virtio/virtio.c:444
  #10 0x00005555558c697a in virtio_blk_handle_vq (s=0x5555575c57e0, vq=0x5555575ceea0) at qemu/hw/block/virtio-blk.c:775
  #11 0x0000555555907836 in virtio_queue_notify_aio_vq (vq=0x5555575ceea0) at qemu/hw/virtio/virtio.c:2244
  #12 0x0000555555cb5dd7 in aio_dispatch_handlers (ctx=ctx@entry=0x55555671a420) at util/aio-posix.c:429
  #13 0x0000555555cb67a8 in aio_dispatch (ctx=0x55555671a420) at util/aio-posix.c:460
  #14 0x0000555555cb307e in aio_ctx_dispatch (source=<optimized out>, callback=<optimized out>, user_data=<optimized out>) at util/async.c:260
  #15 0x00007ffff7bbc510 in g_main_context_dispatch () at /lib64/libglib-2.0.so.0
  #16 0x0000555555cb5848 in glib_pollfds_poll () at util/main-loop.c:219
  #17 os_host_main_loop_wait (timeout=<optimized out>) at util/main-loop.c:242
  #18 main_loop_wait (nonblocking=<optimized out>) at util/main-loop.c:518
  #19 0x00005555559b20c9 in main_loop () at vl.c:1683
  #20 0x0000555555838115 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4441

Reported-by: Alexander Bulekov <alxndr@bu.edu>
Cc: Michael Tsirkin <mst@redhat.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200207104619.164892-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-27 03:45:54 -05:00
Pan Nengyuan
38e245a42c vhost-user-blk: convert to new virtio_delete_queue
use the new virtio_delete_queue function to cleanup.

Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Message-Id: <20200224041336.30790-3-pannengyuan@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:32:56 -05:00
Pan Nengyuan
13e5468127 vhost-user-blk: delete virtioqueues in unrealize to fix memleaks
virtio queues forgot to delete in unrealize, and aslo error path in
realize, this patch fix these memleaks, the leak stack is as follow:

Direct leak of 114688 byte(s) in 16 object(s) allocated from:
    #0 0x7f24024fdbf0 in calloc (/lib64/libasan.so.3+0xcabf0)
    #1 0x7f2401642015 in g_malloc0 (/lib64/libglib-2.0.so.0+0x50015)
    #2 0x55ad175a6447 in virtio_add_queue /mnt/sdb/qemu/hw/virtio/virtio.c:2327
    #3 0x55ad17570cf9 in vhost_user_blk_device_realize /mnt/sdb/qemu/hw/block/vhost-user-blk.c:419
    #4 0x55ad175a3707 in virtio_device_realize /mnt/sdb/qemu/hw/virtio/virtio.c:3509
    #5 0x55ad176ad0d1 in device_set_realized /mnt/sdb/qemu/hw/core/qdev.c:876
    #6 0x55ad1781ff9d in property_set_bool /mnt/sdb/qemu/qom/object.c:2080
    #7 0x55ad178245ae in object_property_set_qobject /mnt/sdb/qemu/qom/qom-qobject.c:26
    #8 0x55ad17821eb4 in object_property_set_bool /mnt/sdb/qemu/qom/object.c:1338
    #9 0x55ad177aeed7 in virtio_pci_realize /mnt/sdb/qemu/hw/virtio/virtio-pci.c:1801

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200224041336.30790-2-pannengyuan@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:32:45 -05:00
Pan Nengyuan
d56e1c8256 virtio-crypto: do delete ctrl_vq in virtio_crypto_device_unrealize
Similar to other virtio-deivces, ctrl_vq forgot to delete in virtio_crypto_device_unrealize, this patch fix it.
This device has aleardy maintained vq pointers. Thus, we use the new virtio_delete_queue function directly to do the cleanup.

The leak stack:
Direct leak of 10752 byte(s) in 3 object(s) allocated from:
    #0 0x7f4c024b1970 in __interceptor_calloc (/lib64/libasan.so.5+0xef970)
    #1 0x7f4c018be49d in g_malloc0 (/lib64/libglib-2.0.so.0+0x5249d)
    #2 0x55a2f8017279 in virtio_add_queue /mnt/sdb/qemu-new/qemu_test/qemu/hw/virtio/virtio.c:2333
    #3 0x55a2f8057035 in virtio_crypto_device_realize /mnt/sdb/qemu-new/qemu_test/qemu/hw/virtio/virtio-crypto.c:814
    #4 0x55a2f8005d80 in virtio_device_realize /mnt/sdb/qemu-new/qemu_test/qemu/hw/virtio/virtio.c:3531
    #5 0x55a2f8497d1b in device_set_realized /mnt/sdb/qemu-new/qemu_test/qemu/hw/core/qdev.c:891
    #6 0x55a2f8b48595 in property_set_bool /mnt/sdb/qemu-new/qemu_test/qemu/qom/object.c:2238
    #7 0x55a2f8b54fad in object_property_set_qobject /mnt/sdb/qemu-new/qemu_test/qemu/qom/qom-qobject.c:26
    #8 0x55a2f8b4de2c in object_property_set_bool /mnt/sdb/qemu-new/qemu_test/qemu/qom/object.c:1390
    #9 0x55a2f80609c9 in virtio_crypto_pci_realize /mnt/sdb/qemu-new/qemu_test/qemu/hw/virtio/virtio-crypto-pci.c:58

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Cc: "Gonglei (Arei)" <arei.gonglei@huawei.com>
Message-Id: <20200225075554.10835-5-pannengyuan@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:32:45 -05:00
Pan Nengyuan
9861546e1d virtio-pmem: do delete rq_vq in virtio_pmem_unrealize
Similar to other virtio-devices, rq_vq forgot to delete in
virtio_pmem_unrealize, this patch fix it.  This device has already
maintained a vq pointer, thus we use the new virtio_delete_queue
function directly to do the cleanup.

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Message-Id: <20200225075554.10835-4-pannengyuan@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:32:45 -05:00
Pan Nengyuan
2e5bc65935 vhost-user-fs: convert to the new virtio_delete_queue function
use the new virtio_delete_queue function to cleanup.

Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200225075554.10835-3-pannengyuan@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:32:45 -05:00
Pan Nengyuan
ba07cf5d3f vhost-user-fs: do delete virtio_queues in unrealize
Similar to other virtio device(https://patchwork.kernel.org/patch/11399237/), virtio queues forgot to delete in unrealize, and aslo error path in realize, this patch fix these memleaks, the leak stack is as follow:
Direct leak of 57344 byte(s) in 1 object(s) allocated from:
    #0 0x7f15784fb970 in __interceptor_calloc (/lib64/libasan.so.5+0xef970)
    #1 0x7f157790849d in g_malloc0 (/lib64/libglib-2.0.so.0+0x5249d)
    #2 0x55587a1bf859 in virtio_add_queue /mnt/sdb/qemu-new/qemu_test/qemu/hw/virtio/virtio.c:2333
    #3 0x55587a2071d5 in vuf_device_realize /mnt/sdb/qemu-new/qemu_test/qemu/hw/virtio/vhost-user-fs.c:212
    #4 0x55587a1ae360 in virtio_device_realize /mnt/sdb/qemu-new/qemu_test/qemu/hw/virtio/virtio.c:3531
    #5 0x55587a63fb7b in device_set_realized /mnt/sdb/qemu-new/qemu_test/qemu/hw/core/qdev.c:891
    #6 0x55587acf03f5 in property_set_bool /mnt/sdb/qemu-new/qemu_test/qemu/qom/object.c:2238
    #7 0x55587acfce0d in object_property_set_qobject /mnt/sdb/qemu-new/qemu_test/qemu/qom/qom-qobject.c:26
    #8 0x55587acf5c8c in object_property_set_bool /mnt/sdb/qemu-new/qemu_test/qemu/qom/object.c:1390
    #9 0x55587a8e22a2 in pci_qdev_realize /mnt/sdb/qemu-new/qemu_test/qemu/hw/pci/pci.c:2095
    #10 0x55587a63fb7b in device_set_realized /mnt/sdb/qemu-new/qemu_test/qemu/hw/core/qdev.c:891
    #11 0x55587acf03f5 in property_set_bool /mnt/sdb/qemu-new/qemu_test/qemu/qom/object.c:2238
    #12 0x55587acfce0d in object_property_set_qobject /mnt/sdb/qemu-new/qemu_test/qemu/qom/qom-qobject.c:26
    #13 0x55587acf5c8c in object_property_set_bool /mnt/sdb/qemu-new/qemu_test/qemu/qom/object.c:1390
    #14 0x55587a496d65 in qdev_device_add /mnt/sdb/qemu-new/qemu_test/qemu/qdev-monitor.c:679

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200225075554.10835-2-pannengyuan@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:32:45 -05:00
Michael S. Tsirkin
6ab425d8a1 rebuild-expected-aml.sh: remind about the process
Remind users of rebuild-expected-aml.sh about the process
to follow. Suppress the warning if allowed file list exists -
that's a big hint user is already aware of the process.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:23:18 -05:00
Michael S. Tsirkin
34b1429ca9 bios-tables-test: default diff command
Most people probably just want diff -u. So let's use that
as the default.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:23:18 -05:00
Michael S. Tsirkin
c01e905f3a bios-tables-test: fix up DIFF generation
Turns out it goes to stdout which is suppressed even with V=1.
Force DIFF output to stderr to make it visible.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-25 08:23:18 -05:00
Michael S. Tsirkin
a7b4384fef bios-tables-test: tell people how to update
For now just a pointer to the source file.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
2020-02-25 08:23:18 -05:00
Peter Maydell
9a8abceb5f * create a new 'tools' manual, and move the documentation for
qemu-img, qemu-nbd, virtfs-proxy-helper, qemu-trace-stap and
    virtiofsd to it
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Merge remote-tracking branch 'remotes/pmaydell/tags/pull-docs-20200225' into staging

 * create a new 'tools' manual, and move the documentation for
   qemu-img, qemu-nbd, virtfs-proxy-helper, qemu-trace-stap and
   virtiofsd to it

# gpg: Signature made Tue 25 Feb 2020 11:00:16 GMT
# gpg:                using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE
# gpg:                issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [ultimate]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-docs-20200225:
  docs: Move tools documentation to tools manual
  docs: Move qemu-option-trace.rst.inc to docs/
  docs: Create new 'tools' manual

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-02-25 11:03:47 +00:00
Peter Maydell
a08b4a9fe6 docs: Move tools documentation to tools manual
Move the following tools documentation files to the new tools manual:

 docs/interop/qemu-img.rst
 docs/interop/qemu-nbd.rst
 docs/interop/virtfs-proxy-helper.rst
 docs/interop/qemu-trace-stap.rst
 docs/interop/virtiofsd.rst

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20200217155415.30949-4-peter.maydell@linaro.org
2020-02-25 10:48:06 +00:00
Peter Maydell
bb43ee6c4f docs: Move qemu-option-trace.rst.inc to docs/
The qemu-option-trace.rst.inc file contains a rST documentation
fragment which describes trace options common to qemu-nbd and
qemu-img.  We put this file into interop/, but we'd like to move the
qemu-nbd and qemu-img files into the tools/ manual.  We could move
the .rst.inc file along with them, but we're eventually going to want
to use it for the main QEMU binary options documentation too, and
that will be in system/.  So move qemu-option-trace.rst.inc to the
top-level docs/ directory, where all these files can include it via

   .. include:: ../qemu-option-trace.rst.inc

This does have the slight downside that we now need to explicitly
tell Make which manuals use this file rather than relying on
a wildcard for all .rst.inc in the manual.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20200217155415.30949-3-peter.maydell@linaro.org
2020-02-25 10:48:05 +00:00
Peter Maydell
65c3542b1f docs: Create new 'tools' manual
Some of the documentation for QEMU "tools" which are standalone
binaries like qemu-img is an awkward fit in our current 5-manual
split. We've put it into "interop", but they're not really
about interoperability.

Create a new top level manual "tools" which will be a better
home for this documentation. This commit creates an empty
initial manual; we will move the relevant documentation
files in a subsequent commit.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20200217155415.30949-2-peter.maydell@linaro.org
2020-02-25 10:48:04 +00:00
Peter Maydell
c1e667d259 Pull request
This pull request contains a virtio-blk/scsi performance optimization, event
 loop scalability improvements, and a qtest-based device fuzzing framework.  I
 am including the fuzzing patches because I have reviewed them and Thomas Huth
 is currently away on leave.
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Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Pull request

This pull request contains a virtio-blk/scsi performance optimization, event
loop scalability improvements, and a qtest-based device fuzzing framework.  I
am including the fuzzing patches because I have reviewed them and Thomas Huth
is currently away on leave.

# gpg: Signature made Sat 22 Feb 2020 08:50:05 GMT
# gpg:                using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request: (31 commits)
  fuzz: add documentation to docs/devel/
  fuzz: add virtio-scsi fuzz target
  fuzz: add virtio-net fuzz target
  fuzz: add i440fx fuzz targets
  fuzz: add configure flag --enable-fuzzing
  fuzz: add target/fuzz makefile rules
  fuzz: add support for qos-assisted fuzz targets
  fuzz: support for fork-based fuzzing.
  main: keep rcu_atfork callback enabled for qtest
  exec: keep ram block across fork when using qtest
  fuzz: add fuzzer skeleton
  libqos: move useful qos-test funcs to qos_external
  libqos: split qos-test and libqos makefile vars
  libqos: rename i2c_send and i2c_recv
  qtest: add in-process incoming command handler
  libqtest: make bufwrite rely on the TransportOps
  libqtest: add a layer of abstraction to send/recv
  qtest: add qtest_server_send abstraction
  fuzz: add FUZZ_TARGET module type
  module: check module wasn't already initialized
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-02-24 11:38:54 +00:00
Alexander Bulekov
e5c59355ae fuzz: add documentation to docs/devel/
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-23-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
472a07a6e2 fuzz: add virtio-scsi fuzz target
The virtio-scsi fuzz target sets up and fuzzes the available virtio-scsi
queues. After an element is placed on a queue, the fuzzer can select
whether to perform a kick, or continue adding elements.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-22-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
b1db8c6316 fuzz: add virtio-net fuzz target
The virtio-net fuzz target feeds inputs to all three virtio-net
virtqueues, and uses forking to avoid leaking state between fuzz runs.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-21-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
04f713242d fuzz: add i440fx fuzz targets
These three targets should simply fuzz reads/writes to a couple ioports,
but they mostly serve as examples of different ways to write targets.
They demonstrate using qtest and qos for fuzzing, as well as using
rebooting and forking to reset state, or not resetting it at all.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-20-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
adc28027ff fuzz: add configure flag --enable-fuzzing
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-19-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
c621dc3e01 fuzz: add target/fuzz makefile rules
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200220041118.23264-18-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
275ab39d86 fuzz: add support for qos-assisted fuzz targets
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-17-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
cb06fdad05 fuzz: support for fork-based fuzzing.
fork() is a simple way to ensure that state does not leak in between
fuzzing runs. Unfortunately, the fuzzer mutation engine relies on
bitmaps which contain coverage information for each fuzzing run, and
these bitmaps should be copied from the child to the parent(where the
mutation occurs). These bitmaps are created through compile-time
instrumentation and they are not shared with fork()-ed processes, by
default. To address this, we create a shared memory region, adjust its
size and map it _over_ the counter region. Furthermore, libfuzzer
doesn't generally expose the globals that specify the location of the
counters/coverage bitmap. As a workaround, we rely on a custom linker
script which forces all of the bitmaps we care about to be placed in a
contiguous region, which is easy to locate and mmap over.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-16-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
d6919e4cb6 main: keep rcu_atfork callback enabled for qtest
The qtest-based fuzzer makes use of forking to reset-state between
tests. Keep the callback enabled, so the call_rcu thread gets created
within the child process.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200220041118.23264-15-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
a028edeaa6 exec: keep ram block across fork when using qtest
Ram blocks were marked MADV_DONTFORK breaking fuzzing-tests which
execute each test-input in a forked process.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-14-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
5f6fd09a97 fuzz: add fuzzer skeleton
tests/fuzz/fuzz.c serves as the entry point for the virtual-device
fuzzer. Namely, libfuzzer invokes the LLVMFuzzerInitialize and
LLVMFuzzerTestOneInput functions, both of which are defined in this
file. This change adds a "FuzzTarget" struct, along with the
fuzz_add_target function, which should be used to define new fuzz
targets.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-13-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
f62a0bff6a libqos: move useful qos-test funcs to qos_external
The moved functions are not specific to qos-test and might be useful
elsewhere. For example the virtual-device fuzzer makes use of them for
qos-assisted fuzz-targets.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-12-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
92ecf9be90 libqos: split qos-test and libqos makefile vars
Most qos-related objects were specified in the qos-test-obj-y variable.
qos-test-obj-y also included qos-test.o which defines a main().
This made it difficult to repurpose qos-test-obj-y to link anything
beside tests/qos-test against libqos. This change separates objects that
are libqos-specific and ones that are qos-test specific into different
variables.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200220041118.23264-11-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
39397a9a76 libqos: rename i2c_send and i2c_recv
The names i2c_send and i2c_recv collide with functions defined in
hw/i2c/core.c. This causes an error when linking against libqos and
softmmu simultaneously (for example when using qtest inproc). Rename the
libqos functions to avoid this.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-id: 20200220041118.23264-10-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
0bd9aef89b qtest: add in-process incoming command handler
The handler allows a qtest client to send commands to the server by
directly calling a function, rather than using a file/CharBackend

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-9-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:48 +00:00
Alexander Bulekov
ca5d464151 libqtest: make bufwrite rely on the TransportOps
When using qtest "in-process" communication, qtest_sendf directly calls
a function in the server (qtest.c). Previously, bufwrite used
socket_send, which bypasses the TransportOps enabling the call into
qtest.c. This change replaces the socket_send calls with ops->send,
maintaining the benefits of the direct socket_send call, while adding
support for in-process qtest calls.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-8-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Alexander Bulekov
075334810b libqtest: add a layer of abstraction to send/recv
This makes it simple to swap the transport functions for qtest commands
to and from the qtest client. For example, now it is possible to
directly pass qtest commands to a server handler that exists within the
same process, without the standard way of writing to a file descriptor.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-7-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Alexander Bulekov
e731d083e3 qtest: add qtest_server_send abstraction
qtest_server_send is a function pointer specifying the handler used to
transmit data to the qtest client. In the standard configuration, this
calls the CharBackend handler, but now it is possible for other types of
handlers, e.g direct-function calls if the qtest client and server
exist within the same process (inproc)

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-id: 20200220041118.23264-6-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Alexander Bulekov
e785e50a5e fuzz: add FUZZ_TARGET module type
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-5-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Alexander Bulekov
46a07579eb module: check module wasn't already initialized
The virtual-device fuzzer must initialize QOM, prior to running
vl:qemu_init, so that it can use the qos_graph to identify the arguments
required to initialize a guest for libqos-assisted fuzzing. This change
prevents errors when vl:qemu_init tries to (re)initialize the previously
initialized QOM module.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200220041118.23264-4-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Alexander Bulekov
7b73386222 softmmu: split off vl.c:main() into main.c
A program might rely on functions implemented in vl.c, but implement its
own main(). By placing main into a separate source file, there are no
complaints about duplicate main()s when linking against vl.o. For
example, the virtual-device fuzzer uses a main() provided by libfuzzer,
and needs to perform some initialization before running the softmmu
initialization. Now, main simply calls three vl.c functions which
handle the guest initialization, main loop and cleanup.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-3-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Alexander Bulekov
bac068e064 softmmu: move vl.c to softmmu/
Move vl.c to a separate directory, similar to linux-user/
Update the chechpatch and get_maintainer scripts, since they relied on
/vl.c for top_of_tree checks.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-2-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Stefan Hajnoczi
7391d34c3c aio-posix: make AioHandler dispatch O(1) with epoll
File descriptor monitoring is O(1) with epoll(7), but
aio_dispatch_handlers() still scans all AioHandlers instead of
dispatching just those that are ready.  This makes aio_poll() O(n) with
respect to the total number of registered handlers.

Add a local ready_list to aio_poll() so that each nested aio_poll()
builds a list of handlers ready to be dispatched.  Since file descriptor
polling is level-triggered, nested aio_poll() calls also see fds that
were ready in the parent but not yet dispatched.  This guarantees that
nested aio_poll() invocations will dispatch all fds, even those that
became ready before the nested invocation.

Since only handlers ready to be dispatched are placed onto the
ready_list, the new aio_dispatch_ready_handlers() function provides O(1)
dispatch.

Note that AioContext polling is still O(n) and currently cannot be fully
disabled.  This still needs to be fixed before aio_poll() is fully O(1).

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20200214171712.541358-6-stefanha@redhat.com
[Fix compilation error on macOS where there is no epoll(87).  The
aio_epoll() prototype was out of date and aio_add_ready_list() needed to
be moved outside the ifdef.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Stefan Hajnoczi
4749079ce0 aio-posix: make AioHandler deletion O(1)
It is not necessary to scan all AioHandlers for deletion.  Keep a list
of deleted handlers instead of scanning the full list of all handlers.

The AioHandler->deleted field can be dropped.  Let's check if the
handler has been inserted into the deleted list instead.  Add a new
QLIST_IS_INSERTED() API for this check.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20200214171712.541358-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Stefan Hajnoczi
195ed8cb36 qemu/queue.h: add QLIST_SAFE_REMOVE()
QLIST_REMOVE() assumes the element is in a list.  It also leaves the
element's linked list pointers dangling.

Introduce a safe version of QLIST_REMOVE() and convert open-coded
instances of this pattern.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20200214171712.541358-4-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Stefan Hajnoczi
ca8c6b2275 aio-posix: don't pass ns timeout to epoll_wait()
Don't pass the nanosecond timeout into epoll_wait(), which expects
milliseconds.

The epoll_wait() timeout value does not matter if qemu_poll_ns()
determined that the poll fd is ready, but passing a value in the wrong
units is still ugly.  Pass a 0 timeout to epoll_wait() instead.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20200214171712.541358-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Stefan Hajnoczi
ff29ed3a33 aio-posix: fix use after leaving scope in aio_poll()
epoll_handler is a stack variable and must not be accessed after it goes
out of scope:

      if (aio_epoll_check_poll(ctx, pollfds, npfd, timeout)) {
          AioHandler epoll_handler;
          ...
          add_pollfd(&epoll_handler);
          ret = aio_epoll(ctx, pollfds, npfd, timeout);
      } ...

  ...

  /* if we have any readable fds, dispatch event */
  if (ret > 0) {
      for (i = 0; i < npfd; i++) {
          nodes[i]->pfd.revents = pollfds[i].revents;
      }
  }

nodes[0] is &epoll_handler, which has already gone out of scope.

There is no need to use pollfds[] for epoll.  We don't need an
AioHandler for the epoll fd.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20200214171712.541358-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Stefan Hajnoczi
8c6b0356b5 util/async: make bh_aio_poll() O(1)
The ctx->first_bh list contains all created BHs, including those that
are not scheduled.  The list is iterated by the event loop and therefore
has O(n) time complexity with respected to the number of created BHs.

Rewrite BHs so that only scheduled or deleted BHs are enqueued.
Only BHs that actually require action will be iterated.

One semantic change is required: qemu_bh_delete() enqueues the BH and
therefore invokes aio_notify().  The
tests/test-aio.c:test_source_bh_delete_from_cb() test case assumed that
g_main_context_iteration(NULL, false) returns false after
qemu_bh_delete() but it now returns true for one iteration.  Fix up the
test case.

This patch makes aio_compute_timeout() and aio_bh_poll() drop from a CPU
profile reported by perf-top(1).  Previously they combined to 9% CPU
utilization when AioContext polling is commented out and the guest has 2
virtio-blk,num-queues=1 and 99 virtio-blk,num-queues=32 devices.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20200221093951.1414693-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Paolo Bonzini
8c3570e339 rcu_queue: add QSLIST functions
QSLIST is the only family of lists for which we do not have RCU-friendly accessors,
add them.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200220103828.24525-1-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Stefan Hajnoczi
f25c0b5479 aio-posix: avoid reacquiring rcu_read_lock() when polling
The first rcu_read_lock/unlock() is expensive.  Nested calls are cheap.

This optimization increases IOPS from 73k to 162k with a Linux guest
that has 2 virtio-blk,num-queues=1 and 99 virtio-blk,num-queues=32
devices.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20200218182708.914552-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Denis Plotnikov
c9b7d9ec21 virtio: increase virtqueue size for virtio-scsi and virtio-blk
The goal is to reduce the amount of requests issued by a guest on
1M reads/writes. This rises the performance up to 4% on that kind of
disk access pattern.

The maximum chunk size to be used for the guest disk accessing is
limited with seg_max parameter, which represents the max amount of
pices in the scatter-geather list in one guest disk request.

Since seg_max is virqueue_size dependent, increasing the virtqueue
size increases seg_max, which, in turn, increases the maximum size
of data to be read/write from a guest disk.

More details in the original problem statment:
https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg03721.html

Suggested-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
Message-id: 20200214074648.958-1-dplotnikov@virtuozzo.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00