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mm: pass VMA instead of MM to follow_pte()

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... and centralize the VM_IO/VM_PFNMAP sanity check in there. We'll
now also perform these sanity checks for direct follow_pte()
invocations.

For generic_access_phys(), we might now check multiple times: nothing to
worry about, really.

Link: https://lkml.kernel.org/r/20240410155527.474777-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Sean Christopherson <seanjc@google.com>	[KVM]
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Fei Li <fei1.li@intel.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Yonghua Huang <yonghua.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
David Hildenbrand 2024-04-10 17:55:26 +02:00 committed by Andrew Morton
parent 3d6586008f
commit 29ae7d96d1
7 changed files with 17 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/s390/pci/pci_mmio.c
View File

@ -169,7 +169,7 @@ SYSCALL_DEFINE3(s390_pci_mmio_write, unsigned long, mmio_addr,
if (!(vma->vm_flags & VM_WRITE)) if (!(vma->vm_flags & VM_WRITE))
goto out_unlock_mmap; goto out_unlock_mmap;
ret = follow_pte(vma->vm_mm, mmio_addr, &ptep, &ptl); ret = follow_pte(vma, mmio_addr, &ptep, &ptl);
if (ret) if (ret)
goto out_unlock_mmap; goto out_unlock_mmap;
@ -308,7 +308,7 @@ SYSCALL_DEFINE3(s390_pci_mmio_read, unsigned long, mmio_addr,
if (!(vma->vm_flags & VM_WRITE)) if (!(vma->vm_flags & VM_WRITE))
goto out_unlock_mmap; goto out_unlock_mmap;
ret = follow_pte(vma->vm_mm, mmio_addr, &ptep, &ptl); ret = follow_pte(vma, mmio_addr, &ptep, &ptl);
if (ret) if (ret)
goto out_unlock_mmap; goto out_unlock_mmap;

5
arch/x86/mm/pat/memtype.c
View File

@ -954,10 +954,7 @@ static int follow_phys(struct vm_area_struct *vma, unsigned long *prot,
pte_t *ptep, pte; pte_t *ptep, pte;
spinlock_t *ptl; spinlock_t *ptl;
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) if (follow_pte(vma, vma->vm_start, &ptep, &ptl))
return -EINVAL;
if (follow_pte(vma->vm_mm, vma->vm_start, &ptep, &ptl))
return -EINVAL; return -EINVAL;
pte = ptep_get(ptep); pte = ptep_get(ptep);

4
drivers/vfio/vfio_iommu_type1.c
View File

@ -518,7 +518,7 @@ static int follow_fault_pfn(struct vm_area_struct *vma, struct mm_struct *mm,
spinlock_t *ptl; spinlock_t *ptl;
int ret; int ret;
ret = follow_pte(vma->vm_mm, vaddr, &ptep, &ptl); ret = follow_pte(vma, vaddr, &ptep, &ptl);
if (ret) { if (ret) {
bool unlocked = false; bool unlocked = false;
@ -532,7 +532,7 @@ static int follow_fault_pfn(struct vm_area_struct *vma, struct mm_struct *mm,
if (ret) if (ret)
return ret; return ret;
ret = follow_pte(vma->vm_mm, vaddr, &ptep, &ptl); ret = follow_pte(vma, vaddr, &ptep, &ptl);
if (ret) if (ret)
return ret; return ret;
} }

3
drivers/virt/acrn/mm.c
View File

@ -187,8 +187,7 @@ int acrn_vm_ram_map(struct acrn_vm *vm, struct acrn_vm_memmap *memmap)
} }
for (i = 0; i < nr_pages; i++) { for (i = 0; i < nr_pages; i++) {
ret = follow_pte(vma->vm_mm, ret = follow_pte(vma, memmap->vma_base + i * PAGE_SIZE,
memmap->vma_base + i * PAGE_SIZE,
&ptep, &ptl); &ptep, &ptl);
if (ret) if (ret)
break; break;

2
include/linux/mm.h
View File

@ -2420,7 +2420,7 @@ void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
unsigned long end, unsigned long floor, unsigned long ceiling); unsigned long end, unsigned long floor, unsigned long ceiling);
int int
copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma); copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma);
int follow_pte(struct mm_struct *mm, unsigned long address, int follow_pte(struct vm_area_struct *vma, unsigned long address,
pte_t **ptepp, spinlock_t **ptlp); pte_t **ptepp, spinlock_t **ptlp);
int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
void *buf, int len, int write); void *buf, int len, int write);

15
mm/memory.c
View File

@ -5926,7 +5926,7 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
/** /**
* follow_pte - look up PTE at a user virtual address * follow_pte - look up PTE at a user virtual address
* @mm: the mm_struct of the target address space * @vma: the memory mapping
* @address: user virtual address * @address: user virtual address
* @ptepp: location to store found PTE * @ptepp: location to store found PTE
* @ptlp: location to store the lock for the PTE * @ptlp: location to store the lock for the PTE
@ -5945,15 +5945,19 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
* *
* Return: zero on success, -ve otherwise. * Return: zero on success, -ve otherwise.
*/ */
int follow_pte(struct mm_struct *mm, unsigned long address, int follow_pte(struct vm_area_struct *vma, unsigned long address,
pte_t **ptepp, spinlock_t **ptlp) pte_t **ptepp, spinlock_t **ptlp)
{ {
struct mm_struct *mm = vma->vm_mm;
pgd_t *pgd; pgd_t *pgd;
p4d_t *p4d; p4d_t *p4d;
pud_t *pud; pud_t *pud;
pmd_t *pmd; pmd_t *pmd;
pte_t *ptep; pte_t *ptep;
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
goto out;
pgd = pgd_offset(mm, address); pgd = pgd_offset(mm, address);
if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd))) if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
goto out; goto out;
@ -6007,11 +6011,8 @@ int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
int offset = offset_in_page(addr); int offset = offset_in_page(addr);
int ret = -EINVAL; int ret = -EINVAL;
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
return -EINVAL;
retry: retry:
if (follow_pte(vma->vm_mm, addr, &ptep, &ptl)) if (follow_pte(vma, addr, &ptep, &ptl))
return -EINVAL; return -EINVAL;
pte = ptep_get(ptep); pte = ptep_get(ptep);
pte_unmap_unlock(ptep, ptl); pte_unmap_unlock(ptep, ptl);
@ -6026,7 +6027,7 @@ retry:
if (!maddr) if (!maddr)
return -ENOMEM; return -ENOMEM;
if (follow_pte(vma->vm_mm, addr, &ptep, &ptl)) if (follow_pte(vma, addr, &ptep, &ptl))
goto out_unmap; goto out_unmap;
if (!pte_same(pte, ptep_get(ptep))) { if (!pte_same(pte, ptep_get(ptep))) {

4
virt/kvm/kvm_main.c
View File

@ -2902,7 +2902,7 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma,
spinlock_t *ptl; spinlock_t *ptl;
int r; int r;
r = follow_pte(vma->vm_mm, addr, &ptep, &ptl); r = follow_pte(vma, addr, &ptep, &ptl);
if (r) { if (r) {
/* /*
* get_user_pages fails for VM_IO and VM_PFNMAP vmas and does * get_user_pages fails for VM_IO and VM_PFNMAP vmas and does
@ -2917,7 +2917,7 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma,
if (r) if (r)
return r; return r;
r = follow_pte(vma->vm_mm, addr, &ptep, &ptl); r = follow_pte(vma, addr, &ptep, &ptl);
if (r) if (r)
return r; return r;
} }