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From: Mugunthan V N <mugunthanvnm@ti•com>
To: Daniel Mack <zonque@gmail•com>, <davem@davemloft•net>
Cc: <julia.lawall@lip6•fr>, <netdev@vger•kernel.org>,
	<george.cherian@ti•com>
Subject: Re: [PATCH 1/2] net: ethernet: cpsw: don't claim IRQs with devm_request_irq()
Date: Wed, 3 Sep 2014 12:57:37 +0530	[thread overview]
Message-ID: <5406C2E9.9010903@ti.com> (raw)
In-Reply-To: <1409676245-13897-1-git-send-email-zonque@gmail.com>

On Tuesday 02 September 2014 10:14 PM, Daniel Mack wrote:
> Julia Lawall spotted a problem with aa1a15e ("net: ethernet: cpsw:
> switch to devres allocations") which introduced a race condition in
> cpsw_probe() by removing explicit interrupt disable calls before
> calling free_netdev(). Hence, an interrupt can fire after free_netdev()
> was called. The same problem exists in cpsw_remove().
> 
> Fix this by reverting the IRQ part of the aforementioned patch and
> handle those resources explicitly.
> 
> Reported-by: Julia Lawall <julia.lawall@lip6•fr>
> Signed-off-by: Daniel Mack <zonque@gmail•com>

CPSW interrupts cannot be triggered as the interrupts are disabled in
priv->wr_regs->tx_en and priv->wr_regs->rx_en inside CPSW module and
these interrupts are enabled only when the device is opened.

In cpsw_remove, CPDMA controller is stopped and interrupts are disabled
in cpsw_ndo_stop(), so there is no chance that an interrupt can occur
during cpsw_remove().

Regards
Mugunthan V N

      parent reply	other threads:[~2014-09-03  7:27 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-09-02 16:44 [PATCH 1/2] net: ethernet: cpsw: don't claim IRQs with devm_request_irq() Daniel Mack
2014-09-02 16:44 ` [PATCH 2/2] net: ethernet: cpsw: fix interrupt lookup logic in cpsw_probe() Daniel Mack
2014-09-03  7:28   ` Mugunthan V N
2014-09-03  7:30     ` Daniel Mack
2014-09-03  8:22       ` Mugunthan V N
2014-09-03  8:23         ` Daniel Mack
2014-09-03  7:27 ` Mugunthan V N [this message]

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