Re: [Qemu-devel] [PULL v2 00/40] ivshmem: Fixes, cleanups, device model split

[Markus Armbruster]

Peter Maydell <address@hidden> writes:

> On 21 March 2016 at 20:43, Markus Armbruster <address@hidden> wrote:
>> Major issues addressed by this series:
>>
>> * The specification document is incomplete and vague.  Rewritten.
>>
>> * When a peer goes away, and its ID gets reused for another one,
>>   interrupts don't work.
>>
>> * When configured for interrupts, we receive shared memory from the
>>   server some time after realize().  This creates a (usually
>>   short-lived) "no shared memory, yet" state.  If the guest wins the
>>   race, it is exposed to this state (known issue, if you count burying
>>   in docs/specs/ as "known").  If migration wins the race, it fails or
>>   corrupts memory.
>>
>> * Interrupts are unreliable in a (usually small) time window after the
>>   destination peer connects.  I believe fixing this will require
>>   changing the client/server protocol, so just document it for now.
>>
>> * The device isn't capable to tell guest software whether it is
>>   configured for interrupts.  Fix that in a new, backwards-compatible
>>   revision of the guest ABI, and bump the PCI revision.  Deprecate the
>>   old revision.
>>
>> * The device properties are a confusing mess and badly checked.
>>   Clean that up.
>>
>> * Migration with interrupts relies on server behavior not guaranteed
>>   by the specification.  Tighten the specification.
>>
>> v2:
>> * PATCH 05: Include ivshmem-test only in configurations that include
>>   the device
>> * PATCH 36: Fix ivshmem-plain not to assert its nonexistent INTx
>
> Hi -- this appears to be missing the git URL to pull from?

Cover letter edit fail, sorry.  Here's output of git-request-pull:

The following changes since commit 6741d38ad0f2405a6e999ebc9550801b01aca479:

  Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging 
(2016-03-17 15:59:42 +0000)

are available in the git repository at:

  git://repo.or.cz/qemu/armbru.git tags/pull-ivshmem-2016-03-18

for you to fetch changes up to a335c6f204eefba8ff935bcee8f31f51d2174119:

  contrib/ivshmem-server: Print "not for production" warning (2016-03-21 
21:29:03 +0100)

----------------------------------------------------------------
ivshmem: Fixes, cleanups, device model split

----------------------------------------------------------------
Markus Armbruster (40):
      target-ppc: Document TOCTTOU in hugepage support
      ivshmem-server: Fix and clean up command line help
      ivshmem-server: Don't overload POSIX shmem and file name
      qemu-doc: Fix ivshmem huge page example
      event_notifier: Make event_notifier_init_fd() #ifdef CONFIG_EVENTFD
      tests/libqos/pci-pc: Fix qpci_pc_iomap() to map BARs aligned
      ivshmem-test: Improve test case /ivshmem/single
      ivshmem-test: Clean up wait for devices to become operational
      ivshmem-test: Improve test cases /ivshmem/server-*
      ivshmem: Rewrite specification document
      ivshmem: Add missing newlines to debug printfs
      ivshmem: Compile debug prints unconditionally to prevent bit-rot
      ivshmem: Clean up after commit 9940c32
      ivshmem: Drop ivshmem_event() stub
      ivshmem: Don't destroy the chardev on version mismatch
      ivshmem: Fix harmless misuse of Error
      ivshmem: Failed realize() can leave migration blocker behind
      ivshmem: Clean up register callbacks
      ivshmem: Clean up MSI-X conditions
      ivshmem: Leave INTx alone when using MSI-X
      ivshmem: Assert interrupts are set up once
      ivshmem: Simplify rejection of invalid peer ID from server
      ivshmem: Disentangle ivshmem_read()
      ivshmem: Plug leaks on unplug, fix peer disconnect
      ivshmem: Receive shared memory synchronously in realize()
      ivshmem: Propagate errors through ivshmem_recv_setup()
      ivshmem: Rely on server sending the ID right after the version
      ivshmem: Drop the hackish test for UNIX domain chardev
      ivshmem: Simplify how we cope with short reads from server
      ivshmem: Tighten check of property "size"
      ivshmem: Implement shm=... with a memory backend
      ivshmem: Simplify memory regions for BAR 2 (shared memory)
      ivshmem: Inline check_shm_size() into its only caller
      qdev: New DEFINE_PROP_ON_OFF_AUTO
      ivshmem: Replace int role_val by OnOffAuto master
      ivshmem: Split ivshmem-plain, ivshmem-doorbell off ivshmem
      ivshmem: Clean up after the previous commit
      ivshmem: Drop ivshmem property x-memdev
      ivshmem: Require master to have ID zero
      contrib/ivshmem-server: Print "not for production" warning

 contrib/ivshmem-server/ivshmem-server.c |   56 +-
 contrib/ivshmem-server/ivshmem-server.h |    4 +-
 contrib/ivshmem-server/main.c           |   98 +--
 default-configs/pci.mak                 |    2 +-
 docs/specs/ivshmem-spec.txt             |  254 +++++++
 docs/specs/ivshmem_device_spec.txt      |  161 -----
 hw/core/qdev-properties.c               |   10 +
 hw/misc/ivshmem.c                       | 1104 +++++++++++++++++--------------
 include/hw/qdev-properties.h            |    3 +
 qemu-doc.texi                           |   47 +-
 target-ppc/kvm.c                        |    6 +
 tests/Makefile                          |    2 +-
 tests/ivshmem-test.c                    |   99 +--
 tests/libqos/pci-pc.c                   |    8 +-
 util/event_notifier-posix.c             |    6 +
 15 files changed, 1031 insertions(+), 829 deletions(-)
 create mode 100644 docs/specs/ivshmem-spec.txt
 delete mode 100644 docs/specs/ivshmem_device_spec.txt