Re: [Qemu-devel] [PATCH for 2.6 v4 0/3] ide: fix loss of the dma/atapi state during migration

["Denis V. Lunev" <den@openvz.org>]

On 04/12/2016 12:47 AM, John Snow wrote:
>
> On 04/11/2016 10:12 AM, Denis V. Lunev wrote:
>> On 04/06/2016 09:40 AM, Denis V. Lunev wrote:
>>> This patch set fixes bugs in the IDE DMA and the IDE ATAPI on
>>> operations to
>>> save/restore the state.
>>>
>>>   From the user point of view this results in IDE timeouts in the guest
>>> when the user reads from the DVD like the following:
>>>
>>> [424332.169229] ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action
>>> 0x6 frozen
>>> [424332.170423] sr 0:0:0:0: [sr0] CDB:
>>> [424332.171234] Read(10): 28 00 00 00 02 e4 00 00 01 00
>>> [424332.172418] ata1.00: cmd a0/01:00:00:00:08/00:00:00:00:00/a0 tag 0
>>> dma 2048 in
>>>            res 40/00:02:00:0c:00/00:00:00:00:00/a0 Emask 0x4 (timeout)
>>> [424332.174877] ata1.00: status: { DRDY }
>>> [424337.212099] ata1: link is slow to respond, please be patient
>>> (ready=0)
>>> [424342.220084] ata1: device not ready (errno=-16), forcing hardreset
>>> [424342.222700] ata1: soft resetting link
>>> [424342.381059] ata1.00: configured for MWDMA2
>>> [424342.383693] ata1: EH complete
>>>
>>> Another similar nasty effects are possible.
>>>
>>> Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
>>> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
>>> Signed-off-by: Denis V. Lunev <den@openvz.org>
>>> CC: John Snow <jsnow@redhat.com>
>>>
>>> Changes from v1:
>>> - added converter of IDE_DMA_* to IDE_RETRY_* (1)
>>> - fixed handling of the IDE_RETRY_HBA at the ide_restart_bh function (3)
>>>
>>> Changes from v2:
>>> - fixed enumeration value ‘IDE_DMA_ATAPI’ not handled in switch for
>>> macio.c (3)
>>>
>>> Changes from v3:
>>> - move the IDE_DMA_ATAPI setting in the cmd_packet func (3)
>>>
>>> Pavel Butsykin (3):
>>>     ide: don't lose pending dma state
>>>     ide: restart atapi dma by re-evaluating command packet
>>>     ide: really restart pending and in-flight atapi dma
>>>
>>>    hw/ide/atapi.c    | 26 ++++++++++++--------------
>>>    hw/ide/core.c     | 39 ++++++++++++++++-----------------------
>>>    hw/ide/internal.h | 36 ++++++++++++++++++++++++++++++++++++
>>>    hw/ide/macio.c    |  2 ++
>>>    hw/ide/pci.c      |  4 ++++
>>>    5 files changed, 70 insertions(+), 37 deletions(-)
>>>
>> ping
> Sorry, I don't appear to have been CC'd on the actual patch emails, so I
> missed them. The individual patch emails also miss the "v4" tag which
> makes them hard to spot.... and it's hard to figure out what's been
> changed or not since my reviewed-by was added to all three patches, even
> though I only acknowledged the first 2/3.
>
this is strange for me - you R-b: was added only to patches 1-2, here is 
a quote

"The patch fixes the restart of both in-flight and pending ATAPI DMA,
following the scheme similar to that of IDE DMA.

Signed-off-by: Pavel Butsykin<pbutsykin@virtuozzo.com>
Signed-off-by: Denis V. Lunev<den@openvz.org>
---
  hw/ide/atapi.c    | 13 ++++++-------
  hw/ide/core.c     | 30 +++++++++++++++---------------
  hw/ide/internal.h | 21 +++++++++++++++++++++
  hw/ide/macio.c    |  2 ++
  4 files changed, 44 insertions(+), 22 deletions(-)"

this letter was sent at "04/06/2016 09:40 AM"

Den