[PATCH v6 21/33] arm64: kvm: Annotate unwind_hint for hyp entry

Chen Zhongjin chenzhongjin at huawei.com
Wed Jun 22 18:49:05 PDT 2022


Symbol __guest_enter and kvm_hyp_vector saved x0, x1 on stack.

Symbol __guest_exit and __guest_exit_panic is reached when resuming
EL2 execution, and the previous stack pointer gets restored.

Add adequate unwind hints.

Signed-off-by: Julien Thierry <jthierry at redhat.com>
Signed-off-by: Chen Zhongjin <chenzhongjin at huawei.com>
---
 arch/arm64/kvm/hyp/entry.S     | 5 +++++
 arch/arm64/kvm/hyp/hyp-entry.S | 3 +++
 2 files changed, 8 insertions(+)

diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S
index 045d4481c820..81e30d56bf28 100644
--- a/arch/arm64/kvm/hyp/entry.S
+++ b/arch/arm64/kvm/hyp/entry.S
@@ -15,6 +15,7 @@
 #include <asm/kvm_mmu.h>
 #include <asm/kvm_mte.h>
 #include <asm/kvm_ptrauth.h>
+#include <asm/unwind_hints.h>
 
 	.text
 
@@ -22,6 +23,7 @@
  * u64 __guest_enter(struct kvm_vcpu *vcpu);
  */
 SYM_CODE_START(__guest_enter)
+	UNWIND_HINT_FUNC
 	// x0: vcpu
 	// x1-x17: clobbered by macros
 	// x29: guest context
@@ -88,6 +90,7 @@ SYM_INNER_LABEL(__guest_exit_panic, SYM_L_GLOBAL)
 	// vcpu x0-x1 on the stack
 
 	// If the hyp context is loaded, go straight to hyp_panic
+	UNWIND_HINT_FUNC
 	get_loaded_vcpu x0, x1
 	cbnz	x0, 1f
 	b	hyp_panic
@@ -110,6 +113,7 @@ SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL)
 	// x1: vcpu
 	// x2-x29,lr: vcpu regs
 	// vcpu x0-x1 on the stack
+	UNWIND_HINT_FUNC sp_offset=16
 
 	add	x1, x1, #VCPU_CONTEXT
 
@@ -199,6 +203,7 @@ abort_guest_exit_end:
 	msr	daifset, #4	// Mask aborts
 	ret
 
+	UNWIND_HINT_FUNC
 	_kvm_extable	abort_guest_exit_start, 9997f
 	_kvm_extable	abort_guest_exit_end, 9997f
 9997:
diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index 4a65262a4f3a..d72143c59707 100644
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -151,6 +151,7 @@ SYM_CODE_END(\label)
 
 .macro valid_vect target
 	.align 7
+	UNWIND_HINT_FUNC
 661:
 	esb
 	stp	x0, x1, [sp, #-16]!
@@ -162,6 +163,7 @@ check_preamble_length 661b, 662b
 
 .macro invalid_vect target
 	.align 7
+	UNWIND_HINT_FUNC
 661:
 	nop
 	stp	x0, x1, [sp, #-16]!
@@ -209,6 +211,7 @@ SYM_CODE_END(__kvm_hyp_vector)
 .macro hyp_ventry	indirect, spectrev2
 	.align	7
 1:	esb
+	UNWIND_HINT_FUNC
 	.if \spectrev2 != 0
 	spectrev2_smccc_wa1_smc
 	.else
-- 
2.17.1




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