Hello, CPU team could improve the tlbop_*. Eg: Design a hardware internal flag bit for SR_TLB_VPN, tlbop_* will invalid it and mtsr SR_TLB_VPN will valid it. So: On Wed, Dec 13, 2017 at 05:03:33PM +0800, Greentime Hu wrote: > mtsr addr1 NDS32_SR_TLB_VPN > interrupt coming > mtsr addr2 NDS32_SR_TLB_VPN <- TLB_VPN has been set to addr2 mtsr SR_TLB_VPN will valid the flag bit > tlbop_rwr(*pte); tlbop_rwr will invalid SR_TLB_VPN flag bit > interrupt finish > tlbop_rwr(*pte); <- it will use the wrong TLB_VPN Because SR_TLB_VPN is in a invalid state, no operation happen on tlbop_rwr. Then they are atomic safe ,no spin_lock_irq need. :) Guo Ren -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html