Re: [Qemu-devel] [PATCH] e1000e: Do not auto-clear ICR bits which aren't set in EIAC

[Peter Maydell <peter.maydell@linaro.org>]

On 16 April 2018 at 16:25, Jan Kiszka <jan.kiszka@siemens.com> wrote:
> On 2018-04-01 23:17, Jan Kiszka wrote:
>> From: Jan Kiszka <jan.kiszka@siemens.com>
>>
>> The spec does not justify clearing of any E1000_ICR_OTHER_CAUSES when
>> E1000_ICR_OTHER is set in EIAC. In fact, removing this code fixes the
>> issue the Linux driver runs into since 4aea7a5c5e94 ("e1000e: Avoid
>> receiver overrun interrupt bursts") and was worked around by
>> 745d0bd3af99 ("e1000e: Remove Other from EIAC").
>>
>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>> ---
>>
>> This resolves the issue I reported on February 18 ("e1000e: MSI-X
>> problem with recent Linux drivers").
>>
>>  hw/net/e1000e_core.c | 4 ----
>>  1 file changed, 4 deletions(-)
>>
>> diff --git a/hw/net/e1000e_core.c b/hw/net/e1000e_core.c
>> index ecf9b15555..d38f025c0f 100644
>> --- a/hw/net/e1000e_core.c
>> +++ b/hw/net/e1000e_core.c
>> @@ -2022,10 +2022,6 @@ e1000e_msix_notify_one(E1000ECore *core, uint32_t cause, uint32_t int_cfg)
>>
>>      effective_eiac = core->mac[EIAC] & cause;
>>
>> -    if (effective_eiac == E1000_ICR_OTHER) {
>> -        effective_eiac |= E1000_ICR_OTHER_CAUSES;
>> -    }
>> -
>>      core->mac[ICR] &= ~effective_eiac;
>>
>>      if (!(core->mac[CTRL_EXT] & E1000_CTRL_EXT_IAME)) {
>>
>
> Ping for this - as well as https://patchwork.ozlabs.org/patch/895476.
>
> Given that q35 uses e1000e by default and many Linux kernel versions no
> longer work, this should likely go into upcoming and stable versions

I'd rather not put it into 2.12 at this point in the release
cycle unless it's a regression from 2.11, I think.

thanks
-- PMM