[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 08 Aug 2012 11:35:26 +0200
From: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
To: "Suzuki K. Poulose" <suzuki@...ibm.com>
CC: linux-kernel@...r.kernel.org, x86@...nel.org,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
Roland McGrath <roland@...hat.com>,
Oleg Nesterov <oleg@...hat.com>,
Srikar Dronamraju <srikar@...ux.vnet.ibm.com>,
Ananth N Mavinakaynahalli <ananth@...ibm.com>,
stan_shebs@...tor.com
Subject: Re: [PATCH 3/5] uprobes: remove check for uprobe variable in handle_swbp()
On 08/08/2012 11:10 AM, Suzuki K. Poulose wrote:
>> --- a/kernel/events/uprobes.c
>> +++ b/kernel/events/uprobes.c
>> @@ -1528,17 +1528,15 @@ cleanup_ret:
>> utask->active_uprobe = NULL;
>> utask->state = UTASK_RUNNING;
>> }
>> - if (uprobe) {
>> - if (!(uprobe->flags & UPROBE_SKIP_SSTEP))
>> + if (!(uprobe->flags & UPROBE_SKIP_SSTEP))
>>
> Shouldn't we check uprobe != NULL before we check the uprobe->flags ?
> i.e, shouldn't the above line be :
>
> if (uprobe && ! (uprobe->flags & UPROBE_SKIP_SSTEP)) ?
The function starts like this:
if (!uprobe) {
if (is_swbp > 0) {
send_sig(SIGTRAP, current, 0);
} else {
instruction_pointer_set(regs, bp_vaddr);
}
return;
}
Which makes uprobe != NULL by the time we get there, no?
Sebastian
--
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/
Powered by blists - more mailing lists