[PATCH] KVM: arm64: Unregister HYP sections from kmemleak in protected mode

[Marc Zyngier]

Booting a KVM host in protected mode with kmemleak quickly results
in a pretty bad crash, as kmemleak doesn't know that the HYP sections
have been taken away.

Make the unregistration from kmemleak part of marking the sections
as HYP-private. The rest of the HYP-specific data is obtained via
the page allocator, which is not subjected to kmemleak.

Fixes: 90134ac9cabb ("KVM: arm64: Protect the .hyp sections from the host")
Signed-off-by: Marc Zyngier <maz at kernel.org>
Cc: Quentin Perret <qperret at google.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: stable at vger.kernel.org # 5.13
---
 arch/arm64/kvm/arm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index e9a2b8f27792..23f12e602878 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -15,6 +15,7 @@
 #include <linux/fs.h>
 #include <linux/mman.h>
 #include <linux/sched.h>
+#include <linux/kmemleak.h>
 #include <linux/kvm.h>
 #include <linux/kvm_irqfd.h>
 #include <linux/irqbypass.h>
@@ -1960,8 +1961,12 @@ static inline int pkvm_mark_hyp(phys_addr_t start, phys_addr_t end)
 }
 
 #define pkvm_mark_hyp_section(__section)		\
+({							\
+	u64 sz = __section##_end - __section##_start;	\
+	kmemleak_free_part(__section##_start, sz);	\
 	pkvm_mark_hyp(__pa_symbol(__section##_start),	\
-			__pa_symbol(__section##_end))
+		      __pa_symbol(__section##_end));	\
+})
 
 static int finalize_hyp_mode(void)
 {
-- 
2.30.2