[PATCH v4 08/20] arm64: entry: organise entry handlers consistently

Mark Rutland mark.rutland at arm.com
Mon Jun 7 02:46:12 PDT 2021


In entry.S we have two comments which distinguish EL0 and EL1 exception
handlers, but the code isn't actually laid out to match, and there are a
few other inconsistencies that would be good to clear up.

This patch organizes the entry handers consistently:

* The handlers are laid out in order of the vectors, to make them easier
  to navigate.

* The inconsistently-applied alignment is removed

* The handlers are consistently marked with SYM_CODE_START_LOCAL()
  rather than SYM_CODE_START_LOCAL_NOALIGN(), giving them the same
  default alignment as other assembly code snippets.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Acked-by: Catalin Marinas <catalin.marinas at arm.com>
Acked-by: Marc Zyngier <maz at kernel.org>
Reviewed-by: Joey Gouly <joey.gouly at arm.com>
Cc: James Morse <james.morse at arm.com>
Cc: Will Deacon <will at kernel.org>
---
 arch/arm64/kernel/entry.S | 78 ++++++++++++++++++++++-------------------------
 1 file changed, 36 insertions(+), 42 deletions(-)

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 8eb3a0a51413..ed7c55d57afe 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -607,65 +607,88 @@ SYM_CODE_END(el1_error_invalid)
 /*
  * EL1 mode handlers.
  */
-	.align	6
-SYM_CODE_START_LOCAL_NOALIGN(el1_sync)
+SYM_CODE_START_LOCAL(el1_sync)
 	kernel_entry 1
 	mov	x0, sp
 	bl	el1_sync_handler
 	kernel_exit 1
 SYM_CODE_END(el1_sync)
 
-	.align	6
-SYM_CODE_START_LOCAL_NOALIGN(el1_irq)
+SYM_CODE_START_LOCAL(el1_irq)
 	kernel_entry 1
 	mov	x0, sp
 	bl	el1_irq_handler
 	kernel_exit 1
 SYM_CODE_END(el1_irq)
 
-SYM_CODE_START_LOCAL_NOALIGN(el1_fiq)
+SYM_CODE_START_LOCAL(el1_fiq)
 	kernel_entry 1
 	mov	x0, sp
 	bl	el1_fiq_handler
 	kernel_exit 1
 SYM_CODE_END(el1_fiq)
 
+SYM_CODE_START_LOCAL(el1_error)
+	kernel_entry 1
+	mov	x0, sp
+	bl	el1_error_handler
+	kernel_exit 1
+SYM_CODE_END(el1_error)
+
 /*
  * EL0 mode handlers.
  */
-	.align	6
-SYM_CODE_START_LOCAL_NOALIGN(el0_sync)
+SYM_CODE_START_LOCAL(el0_sync)
 	kernel_entry 0
 	mov	x0, sp
 	bl	el0_sync_handler
 	b	ret_to_user
 SYM_CODE_END(el0_sync)
 
+SYM_CODE_START_LOCAL(el0_irq)
+	kernel_entry 0
+	mov	x0, sp
+	bl	el0_irq_handler
+	b	ret_to_user
+SYM_CODE_END(el0_irq)
+
+SYM_CODE_START_LOCAL(el0_fiq)
+	kernel_entry 0
+	mov	x0, sp
+	bl	el0_fiq_handler
+	b	ret_to_user
+SYM_CODE_END(el0_fiq)
+
+SYM_CODE_START_LOCAL(el0_error)
+	kernel_entry 0
+	mov	x0, sp
+	bl	el0_error_handler
+	b	ret_to_user
+SYM_CODE_END(el0_error)
+
 #ifdef CONFIG_COMPAT
-	.align	6
-SYM_CODE_START_LOCAL_NOALIGN(el0_sync_compat)
+SYM_CODE_START_LOCAL(el0_sync_compat)
 	kernel_entry 0, 32
 	mov	x0, sp
 	bl	el0_sync_compat_handler
 	b	ret_to_user
 SYM_CODE_END(el0_sync_compat)
 
-	.align	6
-SYM_CODE_START_LOCAL_NOALIGN(el0_irq_compat)
+SYM_CODE_START_LOCAL(el0_irq_compat)
 	kernel_entry 0, 32
 	mov	x0, sp
 	bl	el0_irq_compat_handler
 	b	ret_to_user
 SYM_CODE_END(el0_irq_compat)
 
-SYM_CODE_START_LOCAL_NOALIGN(el0_fiq_compat)
+SYM_CODE_START_LOCAL(el0_fiq_compat)
 	kernel_entry 0, 32
 	mov	x0, sp
 	bl	el0_fiq_compat_handler
 	b	ret_to_user
 SYM_CODE_END(el0_fiq_compat)
 
-SYM_CODE_START_LOCAL_NOALIGN(el0_error_compat)
+SYM_CODE_START_LOCAL(el0_error_compat)
 	kernel_entry 0, 32
 	mov	x0, sp
 	bl	el0_error_compat_handler
@@ -673,35 +696,6 @@ SYM_CODE_START_LOCAL_NOALIGN(el0_error_compat)
 SYM_CODE_END(el0_error_compat)
 #endif
 
-	.align	6
-SYM_CODE_START_LOCAL_NOALIGN(el0_irq)
-	kernel_entry 0
-	mov	x0, sp
-	bl	el0_irq_handler
-	b	ret_to_user
-SYM_CODE_END(el0_irq)
-
-SYM_CODE_START_LOCAL_NOALIGN(el0_fiq)
-	kernel_entry 0
-	mov	x0, sp
-	bl	el0_fiq_handler
-	b	ret_to_user
-SYM_CODE_END(el0_fiq)
-
-SYM_CODE_START_LOCAL(el1_error)
-	kernel_entry 1
-	mov	x0, sp
-	bl	el1_error_handler
-	kernel_exit 1
-SYM_CODE_END(el1_error)
-
-SYM_CODE_START_LOCAL(el0_error)
-	kernel_entry 0
-	mov	x0, sp
-	bl	el0_error_handler
-	b	ret_to_user
-SYM_CODE_END(el0_error)
-
 /*
  * "slow" syscall return path.
  */
-- 
2.11.0




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