Dumps the pKVM hypervisor backtrace from EL1 by reading the unwinded
addresses from the shared stacktrace buffer.
Signed-off-by: Kalesh Singh <kaleshsingh@xxxxxxxxxx>
---
arch/arm64/include/asm/stacktrace/nvhe.h | 49 ++++++++++++++++++++++++
1 file changed, 49 insertions(+)
diff --git a/arch/arm64/include/asm/stacktrace/nvhe.h b/arch/arm64/include/asm/stacktrace/nvhe.h
index c3f94b10f8f0..ec1a4ee21c21 100644
--- a/arch/arm64/include/asm/stacktrace/nvhe.h
+++ b/arch/arm64/include/asm/stacktrace/nvhe.h
@@ -190,5 +190,54 @@ static int notrace unwind_next(struct unwind_state *state)
}
NOKPROBE_SYMBOL(unwind_next);
+#ifdef CONFIG_PROTECTED_NVHE_STACKTRACE
+DECLARE_KVM_NVHE_PER_CPU(unsigned long [NVHE_STACKTRACE_SIZE/sizeof(long)], pkvm_stacktrace);
+
+/**
+ * pkvm_dump_backtrace - Dump the protected nVHE HYP backtrace.
+ *
+ * @hyp_offset: hypervisor offset, used for address translation.
+ *
+ * Dumping of the pKVM HYP backtrace is done by reading the
+ * stack addresses from the shared stacktrace buffer, since the
+ * host cannot direclty access hyperviosr memory in protected
+ * mode.
+ */
+static inline void pkvm_dump_backtrace(unsigned long hyp_offset)
+{
+ unsigned long *stacktrace_pos;
+ unsigned long va_mask, pc;
+
+ stacktrace_pos = (unsigned long *)this_cpu_ptr_nvhe_sym(pkvm_stacktrace);
+ va_mask = GENMASK_ULL(vabits_actual - 1, 0);
+
+ kvm_err("Protected nVHE HYP call trace:\n");
+
+ /* The stack trace is terminated by a null entry */
+ for (; *stacktrace_pos; stacktrace_pos++) {
+ /* Mask tags and convert to kern addr */
+ pc = (*stacktrace_pos & va_mask) + hyp_offset;
+ kvm_err(" [<%016lx>] %pB\n", pc, (void *)pc);
+ }
+
+ kvm_err("---- End of Protected nVHE HYP call trace ----\n");
+}
+#else /* !CONFIG_PROTECTED_NVHE_STACKTRACE */
+static inline void pkvm_dump_backtrace(unsigned long hyp_offset)
+{
+ kvm_err("Cannot dump pKVM nVHE stacktrace: !CONFIG_PROTECTED_NVHE_STACKTRACE\n");
+}
+#endif /* CONFIG_PROTECTED_NVHE_STACKTRACE */
+
+/**
+ * kvm_nvhe_dump_backtrace - Dump KVM nVHE hypervisor backtrace.
+ *
+ * @hyp_offset: hypervisor offset, used for address translation.
+ */
+static inline void kvm_nvhe_dump_backtrace(unsigned long hyp_offset)
+{
+ if (is_protected_kvm_enabled())
+ pkvm_dump_backtrace(hyp_offset);
+}
#endif /* __KVM_NVHE_HYPERVISOR__ */
#endif /* __ASM_STACKTRACE_NVHE_H */
--
2.37.0.170.g444d1eabd0-goog
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