linux-kernel - Re: Avoid needless loop in sdhci

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAA+hA=R=hZfr6Kx_5X8PQ1ck+1wD3C6LOiXyKNMN7yrqdA0YqA@mail.gmail.com>
Date:	Tue, 5 Nov 2013 14:39:43 +0800
From:	Dong Aisheng <dongas86@...il.com>
To:	Alexey Neyman <stilor@....net>
Cc:	Chris Ball <cjb@...top.org>,
	"linux-mmc@...r.kernel.org" <linux-mmc@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: Avoid needless loop in sdhci_irq() for Card Interrupt

Hi Alexey,

On Tue, Nov 5, 2013 at 2:43 AM, Alexey Neyman <stilor@....net> wrote:
> [Patch ping #3: anyone interested in making sdhci_irq a bit faster?]
>
> Hi all,
>
> I've discovered that the sdhci_irq() function needlessly iterates re-reading
> the interrupt status and doing nothing (until it runs out of max_loops) when
> it handles the "Card Interrupt" status in the interrupt status register.
>
> The reason is that the "Card Interrupt" bit is not cleared until the
> sdhci_irq() calls mmc_signal_sdio_irq(), so if Card Interrupt was asserted,
> re-reading the interrupt status will find this bit set over and over, even if
> no other bits are reported.
>
> The fix: ignore Card Interrupt bits in the interrupt status if we already know
> that mmc_signal_sdio_irq() is going to be called at the end of sdhci_irq().
>
> Signed-off-by: Alexey Neyman <stilor@....net>

I also noticed this issue.
Your fix looks correct to me.
But as following community working way, you need send out patches formerly,
not attach a diff file.
You can refer to 'git send-email' or try with gmail.

BTW, please enrich your patch commit message.

Regards
Dong Aisheng
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/