Re: [Qemu-devel] [PATCH 0/3] ahci: fix completion race condition

[Philippe Mathieu-Daudé]

Hi Bruce,

On 05/31/2018 09:21 AM, Bruce Rogers wrote:
>>>> On 5/30/2018 at 6:43 PM, John Snow <address@hidden> wrote:
>> Commit d759c951f changed the main thread lock release/reacquisition,
>> and in so doing apparently jostled loose a race condition in the AHCI
>> code.
>>
>> Patch 2 should be sufficient to fix this, and patches 1 and 3 are just
>> little trivial fixes.
>>
>> This might be sufficient to fix the bug as reported at
>> https://bugs.launchpad.net/qemu/+bug/1769189 
>> but the nature of the timing changes make it difficult to confirm,
>> so I am posting this patchset for the reporters to help test.
>>
>> John Snow (3):
>>   ahci: trim signatures on raise/lower
>>   ahci: fix PxCI register race
>>   ahci: don't schedule unnecessary BH
>>
>>  hw/ide/ahci.c | 24 +++++++++++‑‑‑‑‑‑‑‑‑‑‑‑‑
>>  1 file changed, 11 insertions(+), 13 deletions(‑)
>>
>> ‑‑ 
>> 2.14.3
> 
> In my case, I applied these 3 patches on top of v2.12 qemu under which
> I can fairly reliably reproduce Windows10 disk delays. With these patches,
> after quite a number of attempts, I no longer can reproduce the failure
> case, so from my perspective it solves the issue.

Does that implicitly mean John can use your "Tested-by: Bruce Rogers
<address@hidden>" tag?