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Date: Tue, 14 Dec 2004 12:31:24 -0800
From: Chris Wright <chrisw@osdl.org>
To: ramos_fabiano@yahoo.com.br
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: Re: help with access_process_vm
Message-ID: <20041214123124.R469@build.pdx.osdl.net>
References: <5afb2c65041214112577ff4a18@mail.gmail.com>
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In-Reply-To: <5afb2c65041214112577ff4a18@mail.gmail.com>; from fabiano.ramos@gmail.com on Tue, Dec 14, 2004 at 05:25:23PM -0200
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* Fabiano Ramos (fabiano.ramos@gmail.com) wrote:
> But the first time a call access_process_vm, dmesg shows me:
>      
> Debug: sleeping function called from invalid context at include/linux/rwsem.h:43
> in_atomic():0, irqs_disabled():1
>  [<c01145ac>] __might_sleep+0x8c/0xa0
>  [<c011c69b>] access_process_vm+0x4b/0x1d0
>  [<c010c830>] do_debug_new+0xd0/0x190
>  [<c038c755>] schedule+0x275/0x460
>  [<c0105c2d>] error_code+0x2d/0x40
> 
> What I am missing?

The access_process_vm() call is doing down_read(), which could sleep,
with irqs disabled.  That's what's wrong.

thanks,
-chris