[tip: x86/seves] x86/sev-es: Use GHCB accessor for setting the MMIO scratch buffer

[tip-bot2 for Tom Lendacky]

The following commit has been merged into the x86/seves branch of tip:

Commit-ID:     0ddfb1cf3b6b07c97cff16ea69931d986f9622ee
Gitweb:        https://git.kernel.org/tip/0ddfb1cf3b6b07c97cff16ea69931d986f9622ee
Author:        Tom Lendacky <thomas.lendacky@xxxxxxx>
AuthorDate:    Fri, 25 Sep 2020 08:38:26 -05:00
Committer:     Borislav Petkov <bp@xxxxxxx>
CommitterDate: Fri, 25 Sep 2020 17:12:41 +02:00

x86/sev-es: Use GHCB accessor for setting the MMIO scratch buffer

Use ghcb_set_sw_scratch() to set the GHCB scratch field, which will also
set the corresponding bit in the GHCB valid_bitmap field to denote that
sw_scratch is actually valid.

Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Joerg Roedel <jroedel@xxxxxxx>
Link: https://lkml.kernel.org/r/ba84deabdf44a7a880454fb351d189c6ad79d4ba.1601041106.git.thomas.lendacky@xxxxxxx
---
 arch/x86/kernel/sev-es.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 6fcfdd3..4a96726 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -751,7 +751,7 @@ static enum es_result vc_do_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt,
 	/* Can never be greater than 8 */
 	exit_info_2 = bytes;
 
-	ghcb->save.sw_scratch = ghcb_pa + offsetof(struct ghcb, shared_buffer);
+	ghcb_set_sw_scratch(ghcb, ghcb_pa + offsetof(struct ghcb, shared_buffer));
 
 	return sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, exit_info_1, exit_info_2);
 }