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[kvm-unit-tests,v1,09/18] arm/arm64: Zero secondary CPUs' stack

Message ID 20231130090722.2897974-10-shahuang@redhat.com (mailing list archive)
State New, archived
Headers show
Series arm/arm64: Rework cache maintenance at boot | expand

Commit Message

Shaoqin Huang Nov. 30, 2023, 9:07 a.m. UTC 
From: Alexandru Elisei <alexandru.elisei@arm.com>

For the boot CPU, the entire stack is zeroed in the entry code. For the
secondaries, only struct thread_info, which lives at the bottom of the
stack, is zeroed in thread_info_init().

Be consistent and zero the entire stack for the secondaries. This should
also improve reproducibility of the testsuite, as all the stacks will start
with the same contents, which is zero. And now that all the stacks are
zeroed in the entry code, there is no need to explicitely zero struct
thread_info in thread_info_init().

Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Shaoqin Huang <shahuang@redhat.com>
---
 arm/cstart.S          |  6 ++++++
 arm/cstart64.S        | 11 +++++++----
 lib/arm/processor.c   |  1 -
 lib/arm64/processor.c |  1 -
 4 files changed, 13 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/arm/cstart.S b/arm/cstart.S
index b24ecabc..2ecebd1d 100644
--- a/arm/cstart.S
+++ b/arm/cstart.S
@@ -151,7 +151,13 @@  secondary_entry:
 	 */
 	ldr	r1, =secondary_data
 	ldr	r0, [r1]
+	mov	r2, r0
+	lsr	r2, #THREAD_SHIFT
+	lsl	r2, #THREAD_SHIFT
+	add	r3, r2, #THREAD_SIZE
+	zero_range r2, r3, r4, r5
 	mov	sp, r0
+
 	bl	exceptions_init
 	bl	enable_vfp
 
diff --git a/arm/cstart64.S b/arm/cstart64.S
index a8ad6dc8..5ba2fb27 100644
--- a/arm/cstart64.S
+++ b/arm/cstart64.S
@@ -14,10 +14,6 @@ 
 #include <asm/thread_info.h>
 #include <asm/sysreg.h>
 
-#ifdef CONFIG_EFI
-#include "efi/crt0-efi-aarch64.S"
-#else
-
 .macro zero_range, tmp1, tmp2
 9998:	cmp	\tmp1, \tmp2
 	b.eq	9997f
@@ -26,6 +22,10 @@ 
 9997:
 .endm
 
+#ifdef CONFIG_EFI
+#include "efi/crt0-efi-aarch64.S"
+#else
+
 .section .init
 
 /*
@@ -162,6 +162,9 @@  secondary_entry:
 	/* set the stack */
 	adrp	x0, secondary_data
 	ldr	x0, [x0, :lo12:secondary_data]
+	and	x1, x0, #THREAD_MASK
+	add	x2, x1, #THREAD_SIZE
+	zero_range x1, x2
 	mov	sp, x0
 
 	/* finish init in C code */
diff --git a/lib/arm/processor.c b/lib/arm/processor.c
index 9d575968..ceff1c0a 100644
--- a/lib/arm/processor.c
+++ b/lib/arm/processor.c
@@ -117,7 +117,6 @@  void do_handle_exception(enum vector v, struct pt_regs *regs)
 
 void thread_info_init(struct thread_info *ti, unsigned int flags)
 {
-	memset(ti, 0, sizeof(struct thread_info));
 	ti->cpu = mpidr_to_cpu(get_mpidr());
 	ti->flags = flags;
 }
diff --git a/lib/arm64/processor.c b/lib/arm64/processor.c
index 5bcad679..a8ef8c59 100644
--- a/lib/arm64/processor.c
+++ b/lib/arm64/processor.c
@@ -233,7 +233,6 @@  void install_vector_handler(enum vector v, vector_fn fn)
 
 static void __thread_info_init(struct thread_info *ti, unsigned int flags)
 {
-	memset(ti, 0, sizeof(struct thread_info));
 	ti->cpu = mpidr_to_cpu(get_mpidr());
 	ti->flags = flags;
 }