mm/huge_memory: fix vmf_insert_pfn_{pmd, pud}() crash, handle unaligned addresses
Starting with c6f3c5ee40c1 ("mm/huge_memory.c: fix modifying of page
protection by insert_pfn_pmd()") vmf_insert_pfn_pmd() internally calls
pmdp_set_access_flags(). That helper enforces a pmd aligned @address
argument via VM_BUG_ON() assertion.
Update the implementation to take a 'struct vm_fault' argument directly
and apply the address alignment fixup internally to fix crash signatures
like:
kernel BUG at arch/x86/mm/pgtable.c:515!
invalid opcode: 0000 [#1] SMP NOPTI
CPU: 51 PID: 43713 Comm: java Tainted: G OE 4.19.35 #1
[..]
RIP: 0010:pmdp_set_access_flags+0x48/0x50
[..]
Call Trace:
vmf_insert_pfn_pmd+0x198/0x350
dax_iomap_fault+0xe82/0x1190
ext4_dax_huge_fault+0x103/0x1f0
? __switch_to_asm+0x40/0x70
__handle_mm_fault+0x3f6/0x1370
? __switch_to_asm+0x34/0x70
? __switch_to_asm+0x40/0x70
handle_mm_fault+0xda/0x200
__do_page_fault+0x249/0x4f0
do_page_fault+0x32/0x110
? page_fault+0x8/0x30
page_fault+0x1e/0x30
Link: http://lkml.kernel.org/r/155741946350.372037.11148198430068238140.stgit@dwillia2-desk3.amr.corp.intel.com
Fixes: c6f3c5ee40c1 ("mm/huge_memory.c: fix modifying of page protection by insert_pfn_pmd()")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Piotr Balcer <piotr.balcer@intel.com>
Tested-by: Yan Ma <yan.ma@intel.com>
Tested-by: Pankaj Gupta <pagupta@redhat.com>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Chandan Rajendra <chandan@linux.ibm.com>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b6a34b3..c314a36 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -793,11 +793,13 @@ static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
pte_free(mm, pgtable);
}
-vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
- pmd_t *pmd, pfn_t pfn, bool write)
+vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write)
{
+ unsigned long addr = vmf->address & PMD_MASK;
+ struct vm_area_struct *vma = vmf->vma;
pgprot_t pgprot = vma->vm_page_prot;
pgtable_t pgtable = NULL;
+
/*
* If we had pmd_special, we could avoid all these restrictions,
* but we need to be consistent with PTEs and architectures that
@@ -820,7 +822,7 @@ vm_fault_t vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
track_pfn_insert(vma, &pgprot, pfn);
- insert_pfn_pmd(vma, addr, pmd, pfn, pgprot, write, pgtable);
+ insert_pfn_pmd(vma, addr, vmf->pmd, pfn, pgprot, write, pgtable);
return VM_FAULT_NOPAGE;
}
EXPORT_SYMBOL_GPL(vmf_insert_pfn_pmd);
@@ -869,10 +871,12 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
spin_unlock(ptl);
}
-vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
- pud_t *pud, pfn_t pfn, bool write)
+vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write)
{
+ unsigned long addr = vmf->address & PUD_MASK;
+ struct vm_area_struct *vma = vmf->vma;
pgprot_t pgprot = vma->vm_page_prot;
+
/*
* If we had pud_special, we could avoid all these restrictions,
* but we need to be consistent with PTEs and architectures that
@@ -889,7 +893,7 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr,
track_pfn_insert(vma, &pgprot, pfn);
- insert_pfn_pud(vma, addr, pud, pfn, pgprot, write);
+ insert_pfn_pud(vma, addr, vmf->pud, pfn, pgprot, write);
return VM_FAULT_NOPAGE;
}
EXPORT_SYMBOL_GPL(vmf_insert_pfn_pud);
