Commit 3082d33f authored by Cyan Yang's avatar Cyan Yang Committed by Wen Zhiwei
Browse files

RISCV: KVM: use raw_spinlock for critical section in imsic 

stable inclusion
from stable-v6.6.62
commit e01cac3d62845e71c84b4c89be32b2c2eb0c83cc
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IB5BUT

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=e01cac3d62845e71c84b4c89be32b2c2eb0c83cc



--------------------------------

[ Upstream commit 3ec4350d4efb5ccb6bd0e11d9cf7f2be4f47297d ]

For the external interrupt updating procedure in imsic, there was a
spinlock to protect it already. But since it should not be preempted in
any cases, we should turn to use raw_spinlock to prevent any preemption
in case PREEMPT_RT was enabled.

Signed-off-by: default avatarCyan Yang <cyan.yang@sifive.com>
Reviewed-by: default avatarYong-Xuan Wang <yongxuan.wang@sifive.com>
Reviewed-by: default avatarAnup Patel <anup@brainfault.org>
Message-ID: <20240919160126.44487-1-cyan.yang@sifive.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarWen Zhiwei <wenzhiwei@kylinos.cn>
parent d59ced19

arch/riscv/kvm/aia_imsic.c

+4 −4
Original line number Diff line number Diff line
@@ -55,7 +55,7 @@ struct imsic { 
	/* IMSIC SW-file */

	struct imsic_mrif *swfile;

	phys_addr_t swfile_pa;

	spinlock_t swfile_extirq_lock;

	raw_spinlock_t swfile_extirq_lock;

};



#define imsic_vs_csr_read(__c)			\
@@ -622,7 +622,7 @@ static void imsic_swfile_extirq_update(struct kvm_vcpu *vcpu) 
	 * interruptions between reading topei and updating pending status.

	 */



	spin_lock_irqsave(&imsic->swfile_extirq_lock, flags);

	raw_spin_lock_irqsave(&imsic->swfile_extirq_lock, flags);



	if (imsic_mrif_atomic_read(mrif, &mrif->eidelivery) &&

	    imsic_mrif_topei(mrif, imsic->nr_eix, imsic->nr_msis))
@@ -630,7 +630,7 @@ static void imsic_swfile_extirq_update(struct kvm_vcpu *vcpu) 
	else

		kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_EXT);



	spin_unlock_irqrestore(&imsic->swfile_extirq_lock, flags);

	raw_spin_unlock_irqrestore(&imsic->swfile_extirq_lock, flags);

}



static void imsic_swfile_read(struct kvm_vcpu *vcpu, bool clear,
@@ -1051,7 +1051,7 @@ int kvm_riscv_vcpu_aia_imsic_init(struct kvm_vcpu *vcpu) 
	}

	imsic->swfile = page_to_virt(swfile_page);

	imsic->swfile_pa = page_to_phys(swfile_page);

	spin_lock_init(&imsic->swfile_extirq_lock);

	raw_spin_lock_init(&imsic->swfile_extirq_lock);



	/* Setup IO device */

	kvm_iodevice_init(&imsic->iodev, &imsic_iodoev_ops);