Commit Graph

55 Commits

Author SHA1 Message Date
Michael S. Tsirkin b834226b04 vhost: optimize interrupt enable/disable
As we now only update used ring after enabling
the backend, we can write flags with __put_user:
as that's done on data path, it matters.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 17:17:28 +03:00
Michael S. Tsirkin 75fd9edc10 vhost: fix zcopy reference counting
Fix get/put refcount imbalance with zero copy,
which caused qemu to hang forever on guest driver unload.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 13:28:34 +03:00
Jason Wang 2723feaa8e vhost: set log when updating used flags or avail event
We need to log writes when updating used flags and avail event
fields.  Otherwise the guest may see a stale value after migration and
miss notifying the host.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 13:28:34 +03:00
Jason Wang f59281dafb vhost: init used ring after backend was set
Move the used ring initialization after backend was set. This
makes it possible to disable the backend and tweak the used ring,
then restart. This will also make it possible to log the used ring
write correctly.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 13:28:34 +03:00
Michael S. Tsirkin bab632d69e vhost: vhost TX zero-copy support
>From: Shirley Ma <mashirle@us.ibm.com>

This adds experimental zero copy support in vhost-net,
disabled by default. To enable, set
experimental_zcopytx module option to 1.

This patch maintains the outstanding userspace buffers in the
sequence it is delivered to vhost. The outstanding userspace buffers
will be marked as done once the lower device buffers DMA has finished.
This is monitored through last reference of kfree_skb callback. Two
buffer indices are used for this purpose.

The vhost-net device passes the userspace buffers info to lower device
skb through message control. DMA done status check and guest
notification are handled by handle_tx: in the worst case is all buffers
in the vq are in pending/done status, so we need to notify guest to
release DMA done buffers first before we get any new buffers from the
vq.

One known problem is that if the guest stops submitting
buffers, buffers might never get used until some
further action, e.g. device reset. This does not
seem to affect linux guests.

Signed-off-by: Shirley <xma@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-18 10:42:32 -07:00
Michael S. Tsirkin 8ea8cf89e1 vhost: support event index
Support the new event index feature. When acked,
utilize it to reduce the # of interrupts sent to the guest.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-05-30 11:14:15 +09:30
Rob Landley 6151658751 Correct occurrences of
- Documentation/kvm/ to Documentation/virtual/kvm
- Documentation/uml/ to Documentation/virtual/uml
- Documentation/lguest/ to Documentation/virtual/lguest
throughout the kernel source tree.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
2011-05-06 09:27:55 -07:00
Michael S. Tsirkin fcc042a280 vhost: copy_from_user -> __copy_from_user
copy_from_user is pretty high on perf top profile,
replacing it with __copy_from_user helps.
It's also safe because we do access_ok checks during setup.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-08 18:03:05 +02:00
Krishna Kumar d47effe1be vhost: Cleanup vhost.c and net.c
Minor cleanup of vhost.c and net.c to match coding style.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-08 18:02:47 +02:00
Michael S. Tsirkin 0174b0c30a vhost: fix signed/unsigned comparison
To detect that a sequence number is done, we are doing math on unsigned
integers so the result is unsigned too. Not what was intended for the <=
comparison. The result is user stuck forever in flush call.
Convert to int to fix this.

Further, get rid of ({}) to make code clearer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-01-10 10:03:39 +02:00
Michael S. Tsirkin 28831ee60b vhost: better variable name in logging
We really store a page offset in write_address,
so rename it write_page to avoid confusion.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-12-09 16:00:10 +02:00
Michael S. Tsirkin 3bf9be40ff vhost: correctly set bits of dirty pages
Fix two bugs in dirty page logging:
When counting pages we should increase address by 1 instead of
VHOST_PAGE_SIZE. Make log_write() correctly process requests
that cross pages with write_address not starting at page boundary.

Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-12-09 15:39:17 +02:00
Michael S. Tsirkin bf5e0bd27f vhost: remove unused include
vhost.c does not need to know about sockets,
don't include sock.h

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-12-09 15:39:13 +02:00
Michael S. Tsirkin 8b7347aab6 vhost: get/put_user -> __get/__put_user
We do access_ok checks on all ring values on an ioctl,
so we don't need to redo them on each access.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-11-04 13:22:12 +02:00
Michael S. Tsirkin dfe5ac5b18 vhost: copy_to_user -> __copy_to_user
We do access_ok checks at setup time, so we don't need to
redo them on each access.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-11-04 13:22:11 +02:00
Michael S. Tsirkin 64e1c80748 vhost-net: batch use/unuse mm
Move use/unuse mm to vhost.c which makes it possible to batch these
operations.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-11-04 13:22:11 +02:00
Michael S. Tsirkin 533a19b4b8 vhost: put mm after thread stop
makes it possible to batch use/unuse mm

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-11-04 13:22:10 +02:00
Julia Lawall 3fcedec752 drivers/vhost/vhost.c: delete double assignment
Delete successive assignments to the same location.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression i;
@@

*i = ...;
 i = ...;
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-10-26 20:39:30 +02:00
Linus Torvalds 5f05647dd8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1699 commits)
  bnx2/bnx2x: Unsupported Ethtool operations should return -EINVAL.
  vlan: Calling vlan_hwaccel_do_receive() is always valid.
  tproxy: use the interface primary IP address as a default value for --on-ip
  tproxy: added IPv6 support to the socket match
  cxgb3: function namespace cleanup
  tproxy: added IPv6 support to the TPROXY target
  tproxy: added IPv6 socket lookup function to nf_tproxy_core
  be2net: Changes to use only priority codes allowed by f/w
  tproxy: allow non-local binds of IPv6 sockets if IP_TRANSPARENT is enabled
  tproxy: added tproxy sockopt interface in the IPV6 layer
  tproxy: added udp6_lib_lookup function
  tproxy: added const specifiers to udp lookup functions
  tproxy: split off ipv6 defragmentation to a separate module
  l2tp: small cleanup
  nf_nat: restrict ICMP translation for embedded header
  can: mcp251x: fix generation of error frames
  can: mcp251x: fix endless loop in interrupt handler if CANINTF_MERRF is set
  can-raw: add msg_flags to distinguish local traffic
  9p: client code cleanup
  rds: make local functions/variables static
  ...

Fix up conflicts in net/core/dev.c, drivers/net/pcmcia/smc91c92_cs.c and
drivers/net/wireless/ath/ath9k/debug.c as per David
2010-10-23 11:47:02 -07:00
David S. Miller 2198a10b50 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	net/core/dev.c
2010-10-21 08:43:05 -07:00
Dan Carpenter 6d97e55f71 vhost: fix return code for log_access_ok()
access_ok() returns 1 if it's OK otherwise it should return 0.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-10-12 14:32:28 +02:00
Ingo Molnar 556ef63255 Merge commit 'v2.6.36-rc7' into core/rcu
Merge reason: Update from -rc3 to -rc7.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-07 09:43:45 +02:00
Ingo Molnar d4f8f217b8 Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu into core/rcu 2010-10-07 09:43:11 +02:00
Jason Wang e0e9b40647 vhost: max s/g to match qemu
Qemu supports up to UIO_MAXIOV s/g so we have to match that because guest
drivers may rely on this.

Allocate indirect and log arrays dynamically to avoid using too much contigious
memory and make the length of hdr array to match the header length since each
iovec entry has a least one byte.

Test with copying large files w/ and w/o migration in both linux and windows
guests.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-10-05 13:33:43 +02:00
Michael S. Tsirkin 5786aee8bf vhost: fix log ctx signalling
The log eventfd signalling got put in dead code.
We didn't notice because qemu currently does polling
instead of eventfd select.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-09-22 16:21:33 +02:00
Michael S. Tsirkin 615cc2211c vhost: error handling fix
vhost should set worker to NULL on cgroups attach failure,
so that we won't try to destroy the worker again on close.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-09-06 09:49:39 +03:00
Michael S. Tsirkin 87d6a412bd vhost: fix attach to cgroups regression
Since 2.6.36-rc1, non-root users of vhost-net fail to attach
if they are in any cgroups.

The reason is that when qemu uses vhost, vhost wants to attach
its thread to all cgroups that qemu has.  But we got the API backwards,
so a non-priveledged process (Qemu) tried to control
the priveledged one (vhost), which fails.

Fix this by switching to the new cgroup_attach_task_all,
and running it from the vhost thread.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-09-06 09:49:31 +03:00
Eric Dumazet 78b620ce9e vhost: stop worker only if created
Its currently illegal to call kthread_stop(NULL)

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-01 14:26:13 -07:00
Arnd Bergmann 28457ee69c vhost: add __rcu annotations
Also add rcu_dereference_protected() for code paths where locks are held.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
2010-08-21 16:27:36 -07:00
David Stevens 8dd014adfe vhost-net: mergeable buffers support
This adds support for mergeable buffers in vhost-net: this is needed
for older guests without indirect buffer support, as well
as for zero copy with some devices.

Includes changes by Michael S. Tsirkin to make the
patch as low risk as possible (i.e., close to no changes
when feature is disabled).

Signed-off-by: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-07-28 15:45:36 +03:00
Michael S. Tsirkin 9e3d195720 vhost: apply cgroup to vhost workers
Apply the cgroup of the owner task to the created vhost worker.

Based on patches from Sridhar Samudrala's and Tejun Heo.
Later we'll need to also apply cpumask and probably priority
of the owner process.

Discussion on the best way to do this is still ongoing.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Sridhar Samudrala <samudrala.sridhar@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2010-07-28 15:45:18 +03:00
Tejun Heo c23f3445e6 vhost: replace vhost_workqueue with per-vhost kthread
Replace vhost_workqueue with per-vhost kthread.  Other than callback
argument change from struct work_struct * to struct vhost_work *,
there's no visible change to vhost_poll_*() interface.

This conversion is to make each vhost use a dedicated kthread so that
resource control via cgroup can be applied.

Partially based on Sridhar Samudrala's patch.

* Updated to use sub structure vhost_work instead of directly using
  vhost_poll at Michael's suggestion.

* Added flusher wake_up() optimization at Michael's suggestion.

Changes by MST:
* Converted atomics/barrier use to a spinlock.
* Create thread on SET_OWNER
* Fix flushing

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Sridhar Samudrala <samudrala.sridhar@gmail.com>
2010-07-28 15:44:53 +03:00
David S. Miller 597e608a84 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2010-07-07 15:59:38 -07:00
Michael S. Tsirkin 7b3384fc30 vhost: add unlikely annotations to error path
patch 'break out of polling loop on error' caused
a minor performance regression on my machine: recover
that performance by adding a bunch of unlikely annotations
in the error handling.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-07-01 19:25:40 +03:00
Michael S. Tsirkin d5675bd204 vhost: break out of polling loop on error
When ring parsing fails, we currently handle this
as ring empty condition. This means that we enable
kicks and recheck ring empty: if this not empty,
we re-start polling which of course will fail again.

Instead, let's return a negative error code and stop polling.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-06-27 11:52:25 +03:00
David S. Miller 0dea7c12fc Merge branch 'vhost-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost 2010-06-02 08:26:36 -07:00
Linus Torvalds 72da3bc0cb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (22 commits)
  netlink: bug fix: wrong size was calculated for vfinfo list blob
  netlink: bug fix: don't overrun skbs on vf_port dump
  xt_tee: use skb_dst_drop()
  netdev/fec: fix ifconfig eth0 down hang issue
  cnic: Fix context memory init. on 5709.
  drivers/net: Eliminate a NULL pointer dereference
  drivers/net/hamradio: Eliminate a NULL pointer dereference
  be2net: Patch removes redundant while statement in loop.
  ipv6: Add GSO support on forwarding path
  net: fix __neigh_event_send()
  vhost: fix the memory leak which will happen when memory_access_ok fails
  vhost-net: fix to check the return value of copy_to/from_user() correctly
  vhost: fix to check the return value of copy_to/from_user() correctly
  vhost: Fix host panic if ioctl called with wrong index
  net: fix lock_sock_bh/unlock_sock_bh
  net/iucv: Add missing spin_unlock
  net: ll_temac: fix checksum offload logic
  net: ll_temac: fix interrupt bug when interrupt 0 is used
  sctp: dubious bitfields in sctp_transport
  ipmr: off by one in __ipmr_fill_mroute()
  ...
2010-05-28 10:18:40 -07:00
Takuya Yoshikawa a02c37891a vhost: fix the memory leak which will happen when memory_access_ok fails
We need to free newmem when vhost_set_memory() fails to complete.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-05-27 13:55:17 +03:00
Takuya Yoshikawa 7ad9c9d270 vhost: fix to check the return value of copy_to/from_user() correctly
copy_to/from_user() returns the number of bytes that could not be copied.

So we need to check if it is not zero, and in that case, we should return
the error number -EFAULT rather than directly return the return value from
copy_to/from_user().

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-05-27 13:54:59 +03:00
Michael S. Tsirkin f8322fbe04 vhost: whitespace fix
Fix up whitespace in vq_memory_access_ok.

Reported-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-05-27 12:28:03 +03:00
Krishna Kumar 0f3d9a1746 vhost: Fix host panic if ioctl called with wrong index
Missed a boundary value check in vhost_set_vring. The host panics if
idx == nvqs is used in ioctl commands in vhost_virtqueue_init.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-05-27 12:19:02 +03:00
Alexey Dobriyan 4be929be34 kernel-wide: replace USHORT_MAX, SHORT_MAX and SHORT_MIN with USHRT_MAX, SHRT_MAX and SHRT_MIN
- C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not
  USHORT_MAX/SHORT_MAX/SHORT_MIN.

- Make SHRT_MIN of type s16, not int, for consistency.

[akpm@linux-foundation.org: fix drivers/dma/timb_dma.c]
[akpm@linux-foundation.org: fix security/keys/keyring.c]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:02 -07:00
David S. Miller 6811d58fc1 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	include/linux/if_link.h
2010-05-16 22:26:58 -07:00
Michael S. Tsirkin 0d4993563b vhost: fix barrier pairing
According to memory-barriers.txt, an smp memory barrier in guest
should always be paired with an smp memory barrier in host,
and I quote "a lack of appropriate pairing is almost certainly an
error". In case of vhost, failure to flush out used index
update before looking at the interrupt disable flag
could result in missed interrupts, resulting in
networking hang under stress.

This might happen when flags read bypasses used index write.
So we see interrupts disabled and do not interrupt, at the
same time guest writes flags value to enable interrupt,
reads an old used index value, thinks that
used ring is empty and waits for interrupt.

Note: the barrier we pair with here is in
drivers/virtio/virtio_ring.c, function
vring_enable_cb.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Juan Quintela <quintela@redhat.com>
2010-05-12 18:04:04 +03:00
David S. Miller fea0691526 Merge branch 'vhost' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost 2010-04-14 22:52:46 -07:00
Christoph Hellwig a8d3782f9e vhost: fix sparse warnings
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-04-14 11:52:08 +03:00
David S. Miller 4a1032faac Merge branch 'master' of /home/davem/src/GIT/linux-2.6/ 2010-04-11 02:44:30 -07:00
Jeff Dike 179b284e2f vhost-net: fix vq_memory_access_ok error checking
vq_memory_access_ok needs to check whether mem == NULL

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-04-07 17:04:45 +03:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Michael S. Tsirkin 535297a6ae vhost: fix error handling in vring ioctls
Stanse found a locking problem in vhost_set_vring:
several returns from VHOST_SET_VRING_KICK, VHOST_SET_VRING_CALL,
VHOST_SET_VRING_ERR with the vq->mutex held.
Fix these up.

Reported-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Laurent Chavey <chavey@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-03-17 23:07:35 +02:00