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Date:   Thu, 8 Jun 2023 14:25:46 +0300
From:   "kirill.shutemov@linux.intel.com" <kirill.shutemov@linux.intel.com>
To:     "Huang, Kai" <kai.huang@intel.com>
Cc:     "hpa@zytor.com" <hpa@zytor.com>,
        "peterz@infradead.org" <peterz@infradead.org>,
        "rostedt@goodmis.org" <rostedt@goodmis.org>,
        "jpoimboe@kernel.org" <jpoimboe@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
        "Wilk, Konrad" <konrad.wilk@oracle.com>
Subject: Re: [PATCH] x86/kexec: Add a comment to relocate_kernel() for better
 readability
Message-ID: <20230608112546.y7djwgebpuv32tzt@box.shutemov.name>
References: <20230607103910.407779-1-kai.huang@intel.com>
 <20230607111957.sppocwpkhfb2e2vf@box.shutemov.name>
 <538335b164bf8b84b8a55c5654ed15d849479388.camel@intel.com>
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On Thu, Jun 08, 2023 at 04:41:37AM +0000, Huang, Kai wrote:
> On Wed, 2023-06-07 at 14:19 +0300, kirill.shutemov@linux.intel.com wrote:
> > On Wed, Jun 07, 2023 at 10:39:10PM +1200, Kai Huang wrote:
> > > The reason to save %rcx to %r11 before calling swap_pages isn't that
> > > obvious w/o looking into the swap_pages itself.  Add a comment to
> > > improve the readability.
> > > 
> > > Signed-off-by: Kai Huang <kai.huang@intel.com>
> > > ---
> > >  arch/x86/kernel/relocate_kernel_64.S | 4 ++++
> > >  1 file changed, 4 insertions(+)
> > > 
> > > diff --git a/arch/x86/kernel/relocate_kernel_64.S b/arch/x86/kernel/relocate_kernel_64.S
> > > index 56cab1bb25f5..97deae3c5e6c 100644
> > > --- a/arch/x86/kernel/relocate_kernel_64.S
> > > +++ b/arch/x86/kernel/relocate_kernel_64.S
> > > @@ -169,6 +169,10 @@ SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
> > >  	wbinvd
> > >  1:
> > >  
> > > +	/*
> > > +	 * Save the preserve_context to %r11 as
> > > +	 * swap_pages clobbers %rcx.
> > > +	 */
> > 
> > Line split is not needed. It fits nicely under 80-characters.
> > 
> > +	/* Save the preserve_context to %r11 as swap_pages clobbers %rcx. */
> > 
> > Otherwise, LGTM.
> 
> Sure.  Will do.
> 
> With above change, may I add your Acked-by ? :)

Sure.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov