| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <8e8b241b-ef9d-4559-a451-e4cc1067c7fa@lanxincomputing.com>
Date: Wed, 25 Jun 2025 15:43:25 +0800
From: "Nutty Liu" <liujingqi@...xincomputing.com>
To: "Anup Patel" <apatel@...tanamicro.com>,
"Atish Patra" <atish.patra@...ux.dev>
Cc: "Palmer Dabbelt" <palmer@...belt.com>,
"Paul Walmsley" <paul.walmsley@...ive.com>,
"Alexandre Ghiti" <alex@...ti.fr>,
"Andrew Jones" <ajones@...tanamicro.com>,
"Anup Patel" <anup@...infault.org>, <kvm@...r.kernel.org>,
<kvm-riscv@...ts.infradead.org>, <linux-riscv@...ts.infradead.org>,
<linux-kernel@...r.kernel.org>, "Atish Patra" <atishp@...osinc.com>
Subject: Re: [PATCH v3 09/12] RISC-V: KVM: Introduce struct kvm_gstage_mapping
On 6/18/2025 7:35 PM, Anup Patel wrote:
> Introduce struct kvm_gstage_mapping which represents a g-stage
> mapping at a particular g-stage page table level. Also, update
> the kvm_riscv_gstage_map() to return the g-stage mapping upon
> success.
>
> Reviewed-by: Atish Patra <atishp@...osinc.com>
> Signed-off-by: Anup Patel <apatel@...tanamicro.com>
> ---
> arch/riscv/include/asm/kvm_mmu.h | 9 ++++-
> arch/riscv/kvm/mmu.c | 58 ++++++++++++++++++--------------
> arch/riscv/kvm/vcpu_exit.c | 3 +-
> 3 files changed, 43 insertions(+), 27 deletions(-)
>
> diff --git a/arch/riscv/include/asm/kvm_mmu.h b/arch/riscv/include/asm/kvm_mmu.h
> index 4e1654282ee4..91c11e692dc7 100644
> --- a/arch/riscv/include/asm/kvm_mmu.h
> +++ b/arch/riscv/include/asm/kvm_mmu.h
> @@ -8,6 +8,12 @@
>
> #include <linux/kvm_types.h>
>
> +struct kvm_gstage_mapping {
> + gpa_t addr;
> + pte_t pte;
> + u32 level;
> +};
> +
> int kvm_riscv_gstage_ioremap(struct kvm *kvm, gpa_t gpa,
> phys_addr_t hpa, unsigned long size,
> bool writable, bool in_atomic);
> @@ -15,7 +21,8 @@ void kvm_riscv_gstage_iounmap(struct kvm *kvm, gpa_t gpa,
> unsigned long size);
> int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
> struct kvm_memory_slot *memslot,
> - gpa_t gpa, unsigned long hva, bool is_write);
> + gpa_t gpa, unsigned long hva, bool is_write,
> + struct kvm_gstage_mapping *out_map);
> int kvm_riscv_gstage_alloc_pgd(struct kvm *kvm);
> void kvm_riscv_gstage_free_pgd(struct kvm *kvm);
> void kvm_riscv_gstage_update_hgatp(struct kvm_vcpu *vcpu);
> diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
> index c1a3eb076df3..806614b3e46d 100644
> --- a/arch/riscv/kvm/mmu.c
> +++ b/arch/riscv/kvm/mmu.c
> @@ -135,18 +135,18 @@ static void gstage_remote_tlb_flush(struct kvm *kvm, u32 level, gpa_t addr)
> kvm_riscv_hfence_gvma_vmid_gpa(kvm, -1UL, 0, addr, BIT(order), order);
> }
>
> -static int gstage_set_pte(struct kvm *kvm, u32 level,
> - struct kvm_mmu_memory_cache *pcache,
> - gpa_t addr, const pte_t *new_pte)
> +static int gstage_set_pte(struct kvm *kvm,
> + struct kvm_mmu_memory_cache *pcache,
> + const struct kvm_gstage_mapping *map)
> {
> u32 current_level = gstage_pgd_levels - 1;
> pte_t *next_ptep = (pte_t *)kvm->arch.pgd;
> - pte_t *ptep = &next_ptep[gstage_pte_index(addr, current_level)];
> + pte_t *ptep = &next_ptep[gstage_pte_index(map->addr, current_level)];
>
> - if (current_level < level)
> + if (current_level < map->level)
> return -EINVAL;
>
> - while (current_level != level) {
> + while (current_level != map->level) {
> if (gstage_pte_leaf(ptep))
> return -EEXIST;
>
> @@ -165,13 +165,13 @@ static int gstage_set_pte(struct kvm *kvm, u32 level,
> }
>
> current_level--;
> - ptep = &next_ptep[gstage_pte_index(addr, current_level)];
> + ptep = &next_ptep[gstage_pte_index(map->addr, current_level)];
> }
>
> - if (pte_val(*ptep) != pte_val(*new_pte)) {
> - set_pte(ptep, *new_pte);
> + if (pte_val(*ptep) != pte_val(map->pte)) {
> + set_pte(ptep, map->pte);
> if (gstage_pte_leaf(ptep))
> - gstage_remote_tlb_flush(kvm, current_level, addr);
> + gstage_remote_tlb_flush(kvm, current_level, map->addr);
> }
>
> return 0;
> @@ -181,14 +181,16 @@ static int gstage_map_page(struct kvm *kvm,
> struct kvm_mmu_memory_cache *pcache,
> gpa_t gpa, phys_addr_t hpa,
> unsigned long page_size,
> - bool page_rdonly, bool page_exec)
> + bool page_rdonly, bool page_exec,
> + struct kvm_gstage_mapping *out_map)
> {
> - int ret;
> - u32 level = 0;
> - pte_t new_pte;
> pgprot_t prot;
> + int ret;
>
> - ret = gstage_page_size_to_level(page_size, &level);
> + out_map->addr = gpa;
> + out_map->level = 0;
> +
> + ret = gstage_page_size_to_level(page_size, &out_map->level);
> if (ret)
> return ret;
>
> @@ -216,10 +218,10 @@ static int gstage_map_page(struct kvm *kvm,
> else
> prot = PAGE_WRITE;
> }
> - new_pte = pfn_pte(PFN_DOWN(hpa), prot);
> - new_pte = pte_mkdirty(new_pte);
> + out_map->pte = pfn_pte(PFN_DOWN(hpa), prot);
> + out_map->pte = pte_mkdirty(out_map->pte);
>
> - return gstage_set_pte(kvm, level, pcache, gpa, &new_pte);
> + return gstage_set_pte(kvm, pcache, out_map);
> }
>
> enum gstage_op {
> @@ -352,7 +354,6 @@ int kvm_riscv_gstage_ioremap(struct kvm *kvm, gpa_t gpa,
> phys_addr_t hpa, unsigned long size,
> bool writable, bool in_atomic)
> {
> - pte_t pte;
> int ret = 0;
> unsigned long pfn;
> phys_addr_t addr, end;
> @@ -360,22 +361,25 @@ int kvm_riscv_gstage_ioremap(struct kvm *kvm, gpa_t gpa,
> .gfp_custom = (in_atomic) ? GFP_ATOMIC | __GFP_ACCOUNT : 0,
> .gfp_zero = __GFP_ZERO,
> };
> + struct kvm_gstage_mapping map;
>
> end = (gpa + size + PAGE_SIZE - 1) & PAGE_MASK;
> pfn = __phys_to_pfn(hpa);
>
> for (addr = gpa; addr < end; addr += PAGE_SIZE) {
> - pte = pfn_pte(pfn, PAGE_KERNEL_IO);
> + map.addr = addr;
> + map.pte = pfn_pte(pfn, PAGE_KERNEL_IO);
> + map.level = 0;
>
> if (!writable)
> - pte = pte_wrprotect(pte);
> + map.pte = pte_wrprotect(map.pte);
>
> ret = kvm_mmu_topup_memory_cache(&pcache, gstage_pgd_levels);
> if (ret)
> goto out;
>
> spin_lock(&kvm->mmu_lock);
> - ret = gstage_set_pte(kvm, 0, &pcache, addr, &pte);
> + ret = gstage_set_pte(kvm, &pcache, &map);
> spin_unlock(&kvm->mmu_lock);
> if (ret)
> goto out;
> @@ -593,7 +597,8 @@ bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
>
> int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
> struct kvm_memory_slot *memslot,
> - gpa_t gpa, unsigned long hva, bool is_write)
> + gpa_t gpa, unsigned long hva, bool is_write,
> + struct kvm_gstage_mapping *out_map)
> {
> int ret;
> kvm_pfn_t hfn;
> @@ -608,6 +613,9 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
> unsigned long vma_pagesize, mmu_seq;
> struct page *page;
>
> + /* Setup initial state of output mapping */
> + memset(out_map, 0, sizeof(*out_map));
> +
> /* We need minimum second+third level pages */
> ret = kvm_mmu_topup_memory_cache(pcache, gstage_pgd_levels);
> if (ret) {
> @@ -677,10 +685,10 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
> if (writable) {
> mark_page_dirty(kvm, gfn);
> ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT,
> - vma_pagesize, false, true);
> + vma_pagesize, false, true, out_map);
> } else {
> ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT,
> - vma_pagesize, true, true);
> + vma_pagesize, true, true, out_map);
> }
>
> if (ret)
> diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c
> index 965df528de90..6b4694bc07ea 100644
> --- a/arch/riscv/kvm/vcpu_exit.c
> +++ b/arch/riscv/kvm/vcpu_exit.c
> @@ -15,6 +15,7 @@
> static int gstage_page_fault(struct kvm_vcpu *vcpu, struct kvm_run *run,
> struct kvm_cpu_trap *trap)
> {
> + struct kvm_gstage_mapping host_map;
> struct kvm_memory_slot *memslot;
> unsigned long hva, fault_addr;
> bool writable;
> @@ -43,7 +44,7 @@ static int gstage_page_fault(struct kvm_vcpu *vcpu, struct kvm_run *run,
> }
>
> ret = kvm_riscv_gstage_map(vcpu, memslot, fault_addr, hva,
> - (trap->scause == EXC_STORE_GUEST_PAGE_FAULT) ? true : false);
> + (trap->scause == EXC_STORE_GUEST_PAGE_FAULT) ? true : false, &host_map);
> if (ret < 0)
> return ret;
>
Reviewed-by: Nutty Liu <liujingqi@...xincomputing.com>
Thanks,
Nutty
Powered by blists - more mailing lists