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Message-ID: <d64e6e9f-27b9-9bbb-aaf8-fca1681eada5@intel.com>
Date:   Thu, 6 Oct 2022 13:45:56 -0700
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Subject: Re: [PATCH] x86/sgx: Replace kmap/kunmap_atomic calls
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To:     "Fabio M. De Francesco" <fmdefrancesco@gmail.com>,
        linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org,
        Jarkko Sakkinen <jarkko@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
        Kristen Carlson Accardi <kristen@linux.intel.com>
Cc:     ira.weiny@intel.com
References: <20220929160647.362798-1-kristen@linux.intel.com>
 <3694452.kQq0lBPeGt@mypc>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <3694452.kQq0lBPeGt@mypc>
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On 10/6/22 13:37, Fabio M. De Francesco wrote:
> kmap() were not suited in those cases because it might sleep. If the intents 
> of the author are simply map a page while in atomic, so to avoid sleeping in 
> atomic bugs, your conversions looks good. 
> 
> For the reasons above, can you please say something more about why this code 
> needed a kmap_atomic() instead of calling kmap()?

This question is backwards.  kmap_atomic() is the default that folks
use.  You use kmap_atomic() *always* unless you _need_ to sleep or one
of the other kmap()-only things.

Folks don't and shouldn't have to explain why this was using kmap_atomic().