From: David Miller <davem@davemloft.net>
To: harini.katakam@xilinx.com
Cc: nicolas.ferre@microchip.com, rafalo@cadence.com,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
michal.simek@xilinx.com, harinikatakamlinux@gmail.com
Subject: Re: [PATCH] net: macb: Change interrupt and napi enable order in open
Date: Tue, 07 May 2019 12:28:49 -0700 (PDT) [thread overview]
Message-ID: <20190507.122849.1270099594432351727.davem@davemloft.net> (raw)
In-Reply-To: <1557239350-4760-1-git-send-email-harini.katakam@xilinx.com>
From: Harini Katakam <harini.katakam@xilinx.com>
Date: Tue, 7 May 2019 19:59:10 +0530
> Current order in open:
> -> Enable interrupts (macb_init_hw)
> -> Enable NAPI
> -> Start PHY
>
> Sequence of RX handling:
> -> RX interrupt occurs
> -> Interrupt is cleared and interrupt bits disabled in handler
> -> NAPI is scheduled
> -> In NAPI, RX budget is processed and RX interrupts are re-enabled
>
> With the above, on QEMU or fixed link setups (where PHY state doesn't
> matter), there's a chance macb RX interrupt occurs before NAPI is
> enabled. This will result in NAPI being scheduled before it is enabled.
> Fix this macb open by changing the order.
>
> Fixes: ae1f2a56d273 ("net: macb: Added support for many RX queues")
> Signed-off-by: Harini Katakam <harini.katakam@xilinx.com>
Applied and queued up for -stable.
prev parent reply other threads:[~2019-05-07 19:28 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-07 14:29 [PATCH] net: macb: Change interrupt and napi enable order in open Harini Katakam
2019-05-07 15:32 ` Nicolas.Ferre
2019-05-07 19:28 ` David Miller [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190507.122849.1270099594432351727.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=harini.katakam@xilinx.com \
--cc=harinikatakamlinux@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=michal.simek@xilinx.com \
--cc=netdev@vger.kernel.org \
--cc=nicolas.ferre@microchip.com \
--cc=rafalo@cadence.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).