From:   madvenka@linux.microsoft.com
To:     jpoimboe@redhat.com, peterz@infradead.org, chenzhongjin@huawei.com,
        mark.rutland@arm.com, broonie@kernel.org, nobuta.keiya@fujitsu.com,
        sjitindarsingh@gmail.com, catalin.marinas@arm.com, will@kernel.org,
        jamorris@linux.microsoft.com, linux-arm-kernel@lists.infradead.org,
        live-patching@vger.kernel.org, linux-kernel@vger.kernel.org,
        madvenka@linux.microsoft.com
Subject: [RFC PATCH v3 16/22] arm64: Add unwind hints to exception handlers
Date:   Thu,  2 Feb 2023 01:40:30 -0600
Message-Id: <20230202074036.507249-17-madvenka@linux.microsoft.com>
In-Reply-To: <20230202074036.507249-1-madvenka@linux.microsoft.com>
References: <0337266cf19f4c98388e3f6d09f590d9de258dc7>
 <20230202074036.507249-1-madvenka@linux.microsoft.com>
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From: "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com>

Add unwind hints to Interrupt and Exception handlers.

Signed-off-by: Madhavan T. Venkataraman <madvenka@linux.microsoft.com>
---
 arch/arm64/kernel/entry.S | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index e28137d64b76..d73bed56f0e6 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -28,6 +28,7 @@
 #include <asm/thread_info.h>
 #include <asm/asm-uaccess.h>
 #include <asm/unistd.h>
+#include <asm/unwind_hints.h>
 
 	.macro	clear_gp_regs
 	.irp	n,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29
@@ -560,6 +561,7 @@ SYM_CODE_START_LOCAL(el\el\ht\()_\regsize\()_\label)
 	.if \el == 0
 	b	ret_to_user
 	.else
+	UNWIND_HINT_REGS PT_REGS_SIZE
 	b	ret_to_kernel
 	.endif
 SYM_CODE_END(el\el\ht\()_\regsize\()_\label)
@@ -887,6 +889,7 @@ SYM_FUNC_START(call_on_irq_stack)
 	/* Move to the new stack and call the function there */
 	mov	sp, x16
 	blr	x1
+	UNWIND_HINT_IRQ 16
 
 	/*
 	 * Restore the SP from the FP, and restore the FP and LR from the frame
-- 
2.25.1