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Message-ID: <1507135670.2532.138.camel@linux.intel.com>
Subject: Re: [PATCH v8 12/28] x86/insn-eval: Add utility functions to get
 segment selector
From: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
To: Borislav Petkov <bp@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>, Thomas Gleixner <tglx@linutronix.de>,
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Date: Wed, 04 Oct 2017 09:47:50 -0700
In-Reply-To: <20170929115611.ldpldjr7z7ygdgph@pd.tnic>
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On Fri, 2017-09-29 at 13:56 +0200, Borislav Petkov wrote:
> On Thu, Sep 28, 2017 at 11:06:42PM -0700, Ricardo Neri wrote:
> > 
> > I agree. In fact, insn_get_seg_base() does not need insn at all. All it
> > needs is
> > a INAT_SEG_REG_* index. This would make things clear. UMIP (and callers that
> > need to copy_from_user code can do insn_get_seg_base(regs, INAT_SEG_REG_CS).
> > No
> > insn needed.
> Yap.
> 
> > 
> > In fact, it is only the insn_get_addr_ref_xx() family of functions that does
> I think you mean get_addr_ref_xx() here.

Yes.

> 
> > 
> > Do you think the pseudocode above addresses your concerns?
> > 
> > *insn_get_seg_base() will take a INAT_SEG_REG_* index
> > *insn_get_ref_xx() receives an initialized insn that can check for NULL
> > value.
> > *a reworked resolve_seg_reg_idx will clearly check if it can use segment
> > override prefixes and obtain them. If not, it will use default values.
> Makes sense, but send me the final version to take a look at it too.

I just sent a v9 with all these changes as they impacted several patches in the
series.

Thanks and BR,
Ricardo