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From: Marc Zyngier <marc.zyngier@arm.com>
To: linux-arm-kernel@lists.infradead.org,
	kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org
Cc: cdall@cs.columbia.edu, Will Deacon <will.deacon@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>
Subject: [PATCH v2 3/5] ARM: KVM: relax cache maintainance when building page tables
Date: Thu,  2 May 2013 15:39:00 +0100	[thread overview]
Message-ID: <1367505542-2231-4-git-send-email-marc.zyngier@arm.com> (raw)
In-Reply-To: <1367505542-2231-1-git-send-email-marc.zyngier@arm.com>

Patch 5a677ce044f1 (ARM: KVM: switch to a dual-step HYP init code)
introduced code that flushes page tables to the point of coherency.
This is overkill (point of unification is enough and already done),
and actually not required if running on a SMP capable platform
(the HW PTW can snoop other cpus' L1).

Remove this code and let ae8a8b9553bd (ARM: 7691/1: mm: kill unused
TLB_CAN_READ_FROM_L1_CACHE and use ALT_SMP instead) turn it into
a no-op for SMP ARMv7.

Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm/kvm/mmu.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 4a838db..d79b594 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -234,7 +234,6 @@ static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
 		pte = pte_offset_kernel(pmd, addr);
 		kvm_set_pte(pte, pfn_pte(pfn, prot));
 		get_page(virt_to_page(pte));
-		kvm_flush_dcache_to_poc(pte, sizeof(*pte));
 		pfn++;
 	} while (addr += PAGE_SIZE, addr != end);
 }
@@ -261,7 +260,6 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
 			}
 			pmd_populate_kernel(NULL, pmd, pte);
 			get_page(virt_to_page(pmd));
-			kvm_flush_dcache_to_poc(pmd, sizeof(*pmd));
 		}
 
 		next = pmd_addr_end(addr, end);
@@ -299,7 +297,6 @@ static int __create_hyp_mappings(pgd_t *pgdp,
 			}
 			pud_populate(NULL, pud, pmd);
 			get_page(virt_to_page(pud));
-			kvm_flush_dcache_to_poc(pud, sizeof(*pud));
 		}
 
 		next = pgd_addr_end(addr, end);
-- 
1.8.2.1



WARNING: multiple messages have this Message-ID (diff)
From: marc.zyngier@arm.com (Marc Zyngier)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 3/5] ARM: KVM: relax cache maintainance when building page tables
Date: Thu,  2 May 2013 15:39:00 +0100	[thread overview]
Message-ID: <1367505542-2231-4-git-send-email-marc.zyngier@arm.com> (raw)
In-Reply-To: <1367505542-2231-1-git-send-email-marc.zyngier@arm.com>

Patch 5a677ce044f1 (ARM: KVM: switch to a dual-step HYP init code)
introduced code that flushes page tables to the point of coherency.
This is overkill (point of unification is enough and already done),
and actually not required if running on a SMP capable platform
(the HW PTW can snoop other cpus' L1).

Remove this code and let ae8a8b9553bd (ARM: 7691/1: mm: kill unused
TLB_CAN_READ_FROM_L1_CACHE and use ALT_SMP instead) turn it into
a no-op for SMP ARMv7.

Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm/kvm/mmu.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 4a838db..d79b594 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -234,7 +234,6 @@ static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
 		pte = pte_offset_kernel(pmd, addr);
 		kvm_set_pte(pte, pfn_pte(pfn, prot));
 		get_page(virt_to_page(pte));
-		kvm_flush_dcache_to_poc(pte, sizeof(*pte));
 		pfn++;
 	} while (addr += PAGE_SIZE, addr != end);
 }
@@ -261,7 +260,6 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
 			}
 			pmd_populate_kernel(NULL, pmd, pte);
 			get_page(virt_to_page(pmd));
-			kvm_flush_dcache_to_poc(pmd, sizeof(*pmd));
 		}
 
 		next = pmd_addr_end(addr, end);
@@ -299,7 +297,6 @@ static int __create_hyp_mappings(pgd_t *pgdp,
 			}
 			pud_populate(NULL, pud, pmd);
 			get_page(virt_to_page(pud));
-			kvm_flush_dcache_to_poc(pud, sizeof(*pud));
 		}
 
 		next = pgd_addr_end(addr, end);
-- 
1.8.2.1

  parent reply	other threads:[~2013-05-02 14:39 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-02 14:38 [PATCH v2 0/5] ARM: KVM: various mmu related fixes for 3.10 Marc Zyngier
2013-05-02 14:38 ` Marc Zyngier
2013-05-02 14:38 ` [PATCH v2 1/5] ARM: KVM: be more thorough when invalidating TLBs Marc Zyngier
2013-05-02 14:38   ` Marc Zyngier
2013-05-02 15:13   ` Catalin Marinas
2013-05-02 15:13     ` Catalin Marinas
2013-05-08 10:46     ` Marc Zyngier
2013-05-08 10:46       ` Marc Zyngier
2013-05-02 14:38 ` [PATCH v2 2/5] ARM: KVM: remove dead prototype for __kvm_tlb_flush_vmid Marc Zyngier
2013-05-02 14:38   ` Marc Zyngier
2013-05-02 14:39 ` Marc Zyngier [this message]
2013-05-02 14:39   ` [PATCH v2 3/5] ARM: KVM: relax cache maintainance when building page tables Marc Zyngier
2013-05-02 15:00   ` Catalin Marinas
2013-05-02 15:00     ` Catalin Marinas
2013-05-02 15:03   ` Will Deacon
2013-05-02 15:03     ` Will Deacon
2013-05-02 15:15     ` Christoffer Dall
2013-05-02 15:15       ` Christoffer Dall
2013-05-02 15:17       ` Will Deacon
2013-05-02 15:17         ` Will Deacon
2013-05-13  5:17         ` Christoffer Dall
2013-05-13  5:17           ` Christoffer Dall
2013-05-13  8:58           ` Will Deacon
2013-05-13  8:58             ` Will Deacon
2013-05-14 17:05             ` Christoffer Dall
2013-05-14 17:05               ` Christoffer Dall
2013-05-02 14:39 ` [PATCH v2 4/5] ARM: KVM: get rid of S2_PGD_SIZE Marc Zyngier
2013-05-02 14:39   ` Marc Zyngier
2013-05-02 14:39 ` [PATCH v2 5/5] ARM: KVM: use phys_addr_t instead of unsigned long long for HYP PGDs Marc Zyngier
2013-05-02 14:39   ` Marc Zyngier

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