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From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>,
	kernel-janitors@vger.kernel.org, Vinod Koul <vkoul@kernel.org>,
	Jia-Ju Bai <baijiaju1990@gmail.com>,
	dmaengine <dmaengine@vger.kernel.org>,
	Dan Williams <dan.j.williams@intel.com>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] dmaengine: coh901318: Fix a double lock bug in dma_tc_handle()
Date: Mon, 17 Feb 2020 23:24:10 +0100	[thread overview]
Message-ID: <CAMuHMdWaCqZ_zcHuBetAQu4kmoffNw5jvHM5ciTi29MAxL70bg@mail.gmail.com> (raw)
In-Reply-To: <20200217144050.3i4ymbytogod4ijn@kili.mountain>

Hi Dan,

On Mon, Feb 17, 2020 at 3:41 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
> The caller is already holding the lock so this will deadlock.
>
> Fixes: 0b58828c923e ("DMAENGINE: COH 901 318 remove irq counting")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> This is the second double lock bug found using static analysis.  The
> previous one was commit 627469e4445b ("dmaengine: coh901318: Fix a
> double-lock bug").
>
> The fact that this has been broken for ten years suggests that no one
> has the hardware.

Or this only runs CONFIG_SMP=n kernels?
This seems to be used in arch/arm/boot/dts/ste-u300.dts only, and
CONFIG_ARCH_U300 is a ARCH_MULTI_V5 platform, which looks like
it doesn't support SMP?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

  reply	other threads:[~2020-02-17 22:24 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-17 14:40 [PATCH] dmaengine: coh901318: Fix a double lock bug in dma_tc_handle() Dan Carpenter
2020-02-17 22:24 ` Geert Uytterhoeven [this message]
2020-02-19  9:17   ` Vinod Koul
2020-02-19  9:20     ` Geert Uytterhoeven
2020-02-19  9:27       ` Vinod Koul
2020-02-21 14:50     ` Linus Walleij
2020-02-24 16:30       ` Vinod Koul

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