Currently the check functions are stubbed out at EL2. Implement
versions suitable for the constrained EL2 environment.
Signed-off-by: Keir Fraser <[email protected]>
---
arch/arm64/kvm/hyp/nvhe/Makefile | 3 +-
arch/arm64/kvm/hyp/nvhe/list_debug.c | 54 ++++++++++++++++++++++++++++
arch/arm64/kvm/hyp/nvhe/stub.c | 22 ------------
3 files changed, 56 insertions(+), 23 deletions(-)
create mode 100644 arch/arm64/kvm/hyp/nvhe/list_debug.c
delete mode 100644 arch/arm64/kvm/hyp/nvhe/stub.c
diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
index 24b2c2425b38..f9fe4dc21b1f 100644
--- a/arch/arm64/kvm/hyp/nvhe/Makefile
+++ b/arch/arm64/kvm/hyp/nvhe/Makefile
@@ -13,10 +13,11 @@ lib-objs := clear_page.o copy_page.o memcpy.o memset.o
lib-objs := $(addprefix ../../../lib/, $(lib-objs))
obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
- hyp-main.o hyp-smp.o psci-relay.o early_alloc.o stub.o page_alloc.o \
+ hyp-main.o hyp-smp.o psci-relay.o early_alloc.o page_alloc.o \
cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o
obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o
+obj-$(CONFIG_DEBUG_LIST) += list_debug.o
obj-y += $(lib-objs)
##
diff --git a/arch/arm64/kvm/hyp/nvhe/list_debug.c b/arch/arm64/kvm/hyp/nvhe/list_debug.c
new file mode 100644
index 000000000000..d68abd7ea124
--- /dev/null
+++ b/arch/arm64/kvm/hyp/nvhe/list_debug.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 - Google LLC
+ * Author: Keir Fraser <[email protected]>
+ */
+
+#include <linux/list.h>
+#include <linux/bug.h>
+
+static inline __must_check bool nvhe_check_data_corruption(bool v)
+{
+ return v;
+}
+
+#define NVHE_CHECK_DATA_CORRUPTION(condition) \
+ nvhe_check_data_corruption(({ \
+ bool corruption = unlikely(condition); \
+ if (corruption) { \
+ if (IS_ENABLED(CONFIG_BUG_ON_DATA_CORRUPTION)) { \
+ BUG_ON(1); \
+ } else \
+ WARN_ON(1); \
+ } \
+ corruption; \
+ }))
+
+/* The predicates checked here are taken from lib/list_debug.c. */
+
+bool __list_add_valid(struct list_head *new, struct list_head *prev,
+ struct list_head *next)
+{
+ if (NVHE_CHECK_DATA_CORRUPTION(next->prev != prev) ||
+ NVHE_CHECK_DATA_CORRUPTION(prev->next != next) ||
+ NVHE_CHECK_DATA_CORRUPTION(new == prev || new == next))
+ return false;
+
+ return true;
+}
+
+bool __list_del_entry_valid(struct list_head *entry)
+{
+ struct list_head *prev, *next;
+
+ prev = entry->prev;
+ next = entry->next;
+
+ if (NVHE_CHECK_DATA_CORRUPTION(next == LIST_POISON1) ||
+ NVHE_CHECK_DATA_CORRUPTION(prev == LIST_POISON2) ||
+ NVHE_CHECK_DATA_CORRUPTION(prev->next != entry) ||
+ NVHE_CHECK_DATA_CORRUPTION(next->prev != entry))
+ return false;
+
+ return true;
+}
diff --git a/arch/arm64/kvm/hyp/nvhe/stub.c b/arch/arm64/kvm/hyp/nvhe/stub.c
deleted file mode 100644
index c0aa6bbfd79d..000000000000
--- a/arch/arm64/kvm/hyp/nvhe/stub.c
+++ /dev/null
@@ -1,22 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Stubs for out-of-line function calls caused by re-using kernel
- * infrastructure at EL2.
- *
- * Copyright (C) 2020 - Google LLC
- */
-
-#include <linux/list.h>
-
-#ifdef CONFIG_DEBUG_LIST
-bool __list_add_valid(struct list_head *new, struct list_head *prev,
- struct list_head *next)
-{
- return true;
-}
-
-bool __list_del_entry_valid(struct list_head *entry)
-{
- return true;
-}
-#endif
--
2.35.0.rc2.247.g8bbb082509-goog
On Mon, 31 Jan 2022 12:40:53 +0000, Keir Fraser wrote:
> Currently the check functions are stubbed out at EL2. Implement
> versions suitable for the constrained EL2 environment.
Applied to next, thanks!
[1/1] KVM: arm64: pkvm: Implement CONFIG_DEBUG_LIST at Hyp
commit: 4c68d6c0a1757139c791ccf1a781cbd81e35a063
Cheers,
M.
--
Without deviation from the norm, progress is not possible.