xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

parisc: Protect huge page pte changes with spinlocks

Browse Source 
PA-RISC doesn't have atomic instructions to modify page table entries, so it
takes spinlock in the TLB handler and modifies the page table entry
non-atomically. If you modify the page table entry without the spinlock, you
may race with TLB handler on another CPU and your modification may be lost.
Protect against that with usage of purge_tlb_start() and purge_tlb_end() which
handles the TLB spinlock.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v4.4
This commit is contained in:
Helge Deller
2015-11-26 21:14:02 +01:00
parent 2c2277dc8e
commit b0e551313e
2 changed files with 52 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
arch/parisc/include/asm/hugetlb.h
View File

@@ -54,24 +54,12 @@ static inline pte_t huge_pte_wrprotect(pte_t pte)
return pte_wrprotect(pte);
}
static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
pte_t old_pte = *ptep;
set_huge_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
}
void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep);
static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
int huge_ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep,
pte_t pte, int dirty)
{
int changed = !pte_same(*ptep, pte);
if (changed) {
set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
flush_tlb_page(vma, addr);
}
return changed;
}
pte_t pte, int dirty);
static inline pte_t huge_ptep_get(pte_t *ptep)
{