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Date: Thu, 2 Nov 2017 12:07:13 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Ingo Molnar <mingo@kernel.org>
cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>,
        Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
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Subject: Re: [PATCH v10 02/13] x86/insn-eval: Compute linear address in
 several utility functions
In-Reply-To: <20171102085108.pgiem4kplrcmbzh6@gmail.com>
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References: <1509148310-30862-1-git-send-email-ricardo.neri-calderon@linux.intel.com> <1509148310-30862-3-git-send-email-ricardo.neri-calderon@linux.intel.com> <20171102085108.pgiem4kplrcmbzh6@gmail.com>
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On Thu, 2 Nov 2017, Ingo Molnar wrote:
 
> * Ricardo Neri <ricardo.neri-calderon@linux.intel.com> wrote:
> 
> > +	/*
> > +	 * -EDOM means that we must ignore the address_offset. In such a case,
> > +	 * in 64-bit mode the effective address relative to the RIP of the
> > +	 * following instruction.
> > +	 */
> > +	if (*regoff == -EDOM) {
> > +		if (user_64bit_mode(regs))
> > +			tmp = (long)regs->ip + insn->length;
> > +		else
> > +			tmp = 0;
> > +	} else if (*regoff < 0) {
> > +		return -EINVAL;
> > +	} else {
> > +		tmp = (long)regs_get_register(regs, *regoff);
> > +	}
> 
> > +	else
> > +		indx = (long)regs_get_register(regs, indx_offset);
> 
> This and subsequent patches include a disgustly insane amount of type casts - why?
> 
> For example here 'tmp' is 'long', while regs_get_register() returns
> 'unsigned long', but no type cast is necessary for that.
> 
> > +			ret = get_eff_addr_modrm(insn, regs, &addr_offset,
> > +						 &eff_addr);
> 
> Also, please don't break lines slightly longer than 80 cols just to pacify 
> checkpatch (and this holds for other patches as well) - the cure is worse than the 
> illness!

The right thing to do here is to split out stuff into a helper function
which removes the indentation levels or restructure the code to avoid them.

Thanks,

	tglx