linux-wireless.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Felix Fietkau <nbd@openwrt.org>
To: Sujith Manoharan <sujith@msujith.org>
Cc: linux-wireless@vger.kernel.org, kvalo@codeaurora.org
Subject: Re: [PATCH 3.19] ath9k: fix race condition in irq processing during hardware reset
Date: Thu, 15 Jan 2015 10:46:15 +0100	[thread overview]
Message-ID: <54B78C67.1030106@openwrt.org> (raw)
In-Reply-To: <21687.33741.794518.335502@gargle.gargle.HOWL>

On 2015-01-15 10:09, Sujith Manoharan wrote:
> Felix Fietkau wrote:
>> To fix invalid hardware accesses, the commit
>> "ath9k: do not access hardware on IRQs during reset" made the irq
>> handler ignore interrupts emitted after queueing a hardware reset (which
>> disables the IRQ). This left a small time window for the IRQ to get
>> re-enabled by the tasklet, which caused IRQ storms.
>> Instead of returning IRQ_NONE when ATH_OP_HW_RESET is set, disable the
>> IRQ entirely for the duration of the reset.
> 
> Doesn't this make the kill_interrupts() that was added in the earlier
> commit unnecessary now ?
I think it's still a good idea to try to silence interrupts between
queueing a reset and actually performing it.

- Felix

  reply	other threads:[~2015-01-15  9:46 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-14 13:17 [PATCH 3.19] ath9k: fix race condition in irq processing during hardware reset Felix Fietkau
2015-01-15  9:09 ` Sujith Manoharan
2015-01-15  9:46   ` Felix Fietkau [this message]
     [not found] ` <1459283661.83111.1421395216463.JavaMail.zimbra@neratec.com>
2015-01-16  8:00   ` Rico Derrer
2015-01-16 10:41     ` Felix Fietkau
     [not found]       ` <1998405401.90208.1421656011302.JavaMail.zimbra@neratec.com>
2015-01-19  8:26         ` Rico Derrer
2015-01-19 12:37           ` Kalle Valo
2015-01-19 12:36 ` Kalle Valo

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=54B78C67.1030106@openwrt.org \
    --to=nbd@openwrt.org \
    --cc=kvalo@codeaurora.org \
    --cc=linux-wireless@vger.kernel.org \
    --cc=sujith@msujith.org \
    /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).