linux-kernel - Re: [PATCH 1/3] kexec: Do not map the kexec area as decrypted when SEV is active

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Message-ID: <20190325063742.GA12016@zn.tnic>
Date:   Mon, 25 Mar 2019 07:37:42 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     lijiang <lijiang@...hat.com>
Cc:     linux-kernel@...r.kernel.org, kexec@...ts.infradead.org,
        tglx@...utronix.de, mingo@...hat.com, x86@...nel.org,
        hpa@...or.com, akpm@...ux-foundation.org, dyoung@...hat.com,
        brijesh.singh@....com, thomas.lendacky@....com, bhe@...hat.com
Subject: Re: [PATCH 1/3] kexec: Do not map the kexec area as decrypted when
 SEV is active

On Mon, Mar 25, 2019 at 09:58:07AM +0800, lijiang wrote:
> For the SEV virtual machine, it maps the kexec memroy area as
> encrypted, so, no need to invoke this function to change anything.

Look at the code:

set_memory_decrypted->__set_memory_enc_dec

It already *does* invoke this function.

> > 	if (!mem_encrypt_active())
> > 
> > and heads will spin from all the checking of memory encryption aspects.
> > 
> > So this would need a rework so that there are no multiple confusing
> > checks.
> 
> About the three functions, here i copied their comment from the arch/x86/mm/mem_encrypt.c
> Please refer to it.

I know that comment - I have asked for it. Now you go and look at the
code again with your patch applied.

-- 
Regards/Gruss,
    Boris.

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