Re: [PATCH v2] x86/sev-es: Fix SEV-ES INS/OUTS instructions for word, dword, and qword

From: Joerg Roedel
Date: Wed Nov 24 2021 - 08:32:45 EST


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@xxxxxxxxxx>
> Reviewed-by: Marc Orr <marcorr@xxxxxxxxxx>
> Reviewed-by: Peter Gonda <pgonda@xxxxxxxxxx>
> Signed-off-by: Michael Sterritt <sterritt@xxxxxxxxxx>

Reviewed-by: Joerg Roedel <jroedel@xxxxxxx>