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Date: Wed, 15 Aug 2012 18:59:31 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Subject: Re: [PATCH v3 2/2] powerpc: Uprobes port to powerpc
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Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>, peterz@infradead.org,
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On 07/26, Ananth N Mavinakayanahalli wrote:
>
> From: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
>
> This is the port of uprobes to powerpc. Usage is similar to x86.

I am just curious why this series was ignored by powerpc maintainers...

Of course I can not review this code, I know nothing about powerpc,
but the patches look simple/straightforward.

Paul, Benjamin?





Just one question... Shouldn't arch_uprobe_pre_xol() forbid to probe
UPROBE_SWBP_INSN (at least) ?

(I assume that emulate_step() can't handle this case but of course I
 do not understand arch/powerpc/lib/sstep.c)

Note that uprobe_pre_sstep_notifier() sets utask->state = UTASK_BP_HIT
without any checks. This doesn't look right if it was UTASK_SSTEP...

But again, I do not know what powepc will actually do if we try to
single-step over UPROBE_SWBP_INSN.

Oleg.