From acfa74f078b23d670ad04c3a2aa9cec5fbcf5afe Mon Sep 17 00:00:00 2001 From: Shell Date: Tue, 25 Jul 2023 14:07:44 +0800 Subject: [libcpu/arm] fix race condition with ldrex,strex (#7842) Signed-off-by: Shell --- libcpu/arm/cortex-a/context_gcc.S | 3 +++ libcpu/arm/cortex-a/start_gcc.S | 2 -- 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'libcpu/arm') diff --git a/libcpu/arm/cortex-a/context_gcc.S b/libcpu/arm/cortex-a/context_gcc.S index 98080de5c1..da6e6507df 100644 --- a/libcpu/arm/cortex-a/context_gcc.S +++ b/libcpu/arm/cortex-a/context_gcc.S @@ -40,6 +40,7 @@ rt_hw_interrupt_enable: */ .globl rt_hw_context_switch_to rt_hw_context_switch_to: + clrex ldr sp, [r0] @ get new task stack pointer #ifdef RT_USING_SMP @@ -76,6 +77,7 @@ _guest_switch_lvl: */ .globl rt_hw_context_switch rt_hw_context_switch: + clrex stmfd sp!, {lr} @ push pc (lr should be pushed in place of PC) stmfd sp!, {r0-r12, lr} @ push lr & register file @@ -143,6 +145,7 @@ rt_hw_context_switch: .globl rt_interrupt_to_thread .globl rt_hw_context_switch_interrupt rt_hw_context_switch_interrupt: + clrex #ifdef RT_USING_SMP /* r0 :svc_mod context * r1 :addr of from_thread's sp diff --git a/libcpu/arm/cortex-a/start_gcc.S b/libcpu/arm/cortex-a/start_gcc.S index 6ff40b1b31..606620ecfc 100644 --- a/libcpu/arm/cortex-a/start_gcc.S +++ b/libcpu/arm/cortex-a/start_gcc.S @@ -408,8 +408,6 @@ vector_fiq: .globl vector_irq vector_irq: #ifdef RT_USING_SMP - clrex - stmfd sp!, {r0, r1} cps #Mode_SVC mov r0, sp /* svc_sp */ -- cgit v1.3.1