Date:   Wed, 24 Nov 2021 14:28:49 +0100
From:   Joerg Roedel <jroedel@suse.de>
To:     Michael Sterritt <sterritt@google.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        linux-coco@lists.linux.dev, Paolo Bonzini <pbonzini@redhat.com>,
        marcorr@google.com, pgonda@google.com
Subject: Re: [PATCH v2] x86/sev-es: Fix SEV-ES INS/OUTS instructions for
 word, dword, and qword
Message-ID: <YZ4+EYF8dhrzRy2h@suse.de>
References: <20211119232757.176201-1-sterritt@google.com>
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On Fri, Nov 19, 2021 at 03:27:57PM -0800, Michael Sterritt wrote:
> Properly type the operands being passed to __put_user()/__get_user().
> Otherwise, these routines truncate data for dependent instructions
> (e.g., INSW) and only read/write one byte.
> 
> Tested: Tested by sending a string with `REP OUTSW` to a port and then
> reading it back in with `REP INSW` on the same port. Previous behavior
> was to only send and receive the first char of the size. For example,
> word operations for "abcd" would only read/write "ac". With change, the
> full string is now written and read back.
> 
> Fixes: f980f9c31a923 (x86/sev-es: Compile early handler code into kernel image)
> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> Reviewed-by: Marc Orr <marcorr@google.com>
> Reviewed-by: Peter Gonda <pgonda@google.com>
> Signed-off-by: Michael Sterritt <sterritt@google.com>

Reviewed-by: Joerg Roedel <jroedel@suse.de>