diff --git a/xen/arch/arm/include/asm/arm64/flushtlb.h b/xen/arch/arm/include/asm/arm64/flushtlb.h index 7c54315187..001ae4d1c3 100644 --- a/xen/arch/arm/include/asm/arm64/flushtlb.h +++ b/xen/arch/arm/include/asm/arm64/flushtlb.h @@ -12,8 +12,9 @@ * ARM64_WORKAROUND_REPEAT_TLBI: * Modification of the translation table for a virtual address might lead to * read-after-read ordering violation. - * The workaround repeats TLBI+DSB operation for all the TLB flush operations. - * While this is stricly not necessary, we don't want to take any risk. + * The workaround repeats TLBI+DSB ISH operation for all the TLB flush + * operations. While this is strictly not necessary, we don't want to + * take any risk. * * For Xen page-tables the ISB will discard any instructions fetched * from the old mappings. @@ -21,12 +22,17 @@ * For the Stage-2 page-tables the ISB ensures the completion of the DSB * (and therefore the TLB invalidation) before continuing. So we know * the TLBs cannot contain an entry for a mapping we may have removed. + * + * Note that for local TLB flush, using non-shareable (nsh) is sufficient + * (see D5-4929 in ARM DDI 0487H.a). Although, the memory barrier in + * for the workaround is left as inner-shareable to match with Linux + * v6.1-rc8. */ -#define TLB_HELPER(name, tlbop) \ +#define TLB_HELPER(name, tlbop, sh) \ static inline void name(void) \ { \ asm volatile( \ - "dsb ishst;" \ + "dsb " # sh "st;" \ "tlbi " # tlbop ";" \ ALTERNATIVE( \ "nop; nop;", \ @@ -34,25 +40,25 @@ static inline void name(void) \ "tlbi " # tlbop ";", \ ARM64_WORKAROUND_REPEAT_TLBI, \ CONFIG_ARM64_WORKAROUND_REPEAT_TLBI) \ - "dsb ish;" \ + "dsb " # sh ";" \ "isb;" \ : : : "memory"); \ } /* Flush local TLBs, current VMID only. */ -TLB_HELPER(flush_guest_tlb_local, vmalls12e1); +TLB_HELPER(flush_guest_tlb_local, vmalls12e1, nsh); /* Flush innershareable TLBs, current VMID only */ -TLB_HELPER(flush_guest_tlb, vmalls12e1is); +TLB_HELPER(flush_guest_tlb, vmalls12e1is, ish); /* Flush local TLBs, all VMIDs, non-hypervisor mode */ -TLB_HELPER(flush_all_guests_tlb_local, alle1); +TLB_HELPER(flush_all_guests_tlb_local, alle1, nsh); /* Flush innershareable TLBs, all VMIDs, non-hypervisor mode */ -TLB_HELPER(flush_all_guests_tlb, alle1is); +TLB_HELPER(flush_all_guests_tlb, alle1is, ish); /* Flush all hypervisor mappings from the TLB of the local processor. */ -TLB_HELPER(flush_xen_tlb_local, alle2); +TLB_HELPER(flush_xen_tlb_local, alle2, nsh); /* Flush TLB of local processor for address va. */ static inline void __flush_xen_tlb_one_local(vaddr_t va)