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

[Jan Kiszka]

On 2018-04-01 23:17, Jan Kiszka wrote:
> From: Jan Kiszka <address@hidden>
> 
> 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 <address@hidden>
> ---
> 
> 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

Jan

-- 
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux