[PATCH 10/14] KVM: arm64: Trap & emulate the ITS MAPC command

Sebastian Ene
2026-03-10T12:50:14Z

Parse the MAPC command and verify if we need to do any
updates to the shadow if the collection table is
configured with an indirect layout.

Signed-off-by: Sebastian Ene <sebastianene@google.com>
---
arch/arm64/kvm/hyp/nvhe/its_emulate.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/arch/arm64/kvm/hyp/nvhe/its_emulate.c b/arch/arm64/kvm/hyp/nvhe/its_emulate.c
index 7049d307a236..4782a9a24caa 100644
--- a/arch/arm64/kvm/hyp/nvhe/its_emulate.c
+++ b/arch/arm64/kvm/hyp/nvhe/its_emulate.c
@@ -198,6 +198,13 @@ static int process_its_vmapp(struct its_priv_state *its, struct its_cmd_block *c
return track_pfn(its, base_pfn, num_pages, remove);
}

+static int process_its_mapc(struct its_priv_state *its, struct its_cmd_block *cmd)
+{
+ u32 icid = cmd->raw_cmd[2] & GENMASK(15, 0);
+
+ return check_table_update(its, icid, GITS_BASER_TYPE_COLLECTION);
+}
+
static int parse_its_cmdq(struct its_priv_state *its, int offset, ssize_t len)
{
struct its_cmd_block *cmd = its->cmd_hyp_base + offset;
@@ -215,6 +222,10 @@ static int parse_its_cmdq(struct its_priv_state *its, int offset, ssize_t len)
case GITS_CMD_VMAPP:
ret = process_its_vmapp(its, cmd);
break;
+
+ case GITS_CMD_MAPC:
+ ret = process_its_mapc(its, cmd);
+ break;
}

cmd++;
--
2.53.0.473.g4a7958ca14-goog