diff options
Diffstat (limited to 'arch/parisc/mm')
| -rw-r--r-- | arch/parisc/mm/fault.c | 89 | ||||
| -rw-r--r-- | arch/parisc/mm/init.c | 9 |
2 files changed, 93 insertions, 5 deletions
diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c index e9eabf8f14d7..f114e102aaf2 100644 --- a/arch/parisc/mm/fault.c +++ b/arch/parisc/mm/fault.c @@ -425,3 +425,92 @@ out_of_memory: } pagefault_out_of_memory(); } + +/* Handle non-access data TLB miss faults. + * + * For probe instructions, accesses to userspace are considered allowed + * if they lie in a valid VMA and the access type matches. We are not + * allowed to handle MM faults here so there may be situations where an + * actual access would fail even though a probe was successful. + */ +int +handle_nadtlb_fault(struct pt_regs *regs) +{ + unsigned long insn = regs->iir; + int breg, treg, xreg, val = 0; + struct vm_area_struct *vma, *prev_vma; + struct task_struct *tsk; + struct mm_struct *mm; + unsigned long address; + unsigned long acc_type; + + switch (insn & 0x380) { + case 0x280: + /* FDC instruction */ + fallthrough; + case 0x380: + /* PDC and FIC instructions */ + if (printk_ratelimit()) { + pr_warn("BUG: nullifying cache flush/purge instruction\n"); + show_regs(regs); + } + if (insn & 0x20) { + /* Base modification */ + breg = (insn >> 21) & 0x1f; + xreg = (insn >> 16) & 0x1f; + if (breg && xreg) + regs->gr[breg] += regs->gr[xreg]; + } + regs->gr[0] |= PSW_N; + return 1; + + case 0x180: + /* PROBE instruction */ + treg = insn & 0x1f; + if (regs->isr) { + tsk = current; + mm = tsk->mm; + if (mm) { + /* Search for VMA */ + address = regs->ior; + mmap_read_lock(mm); + vma = find_vma_prev(mm, address, &prev_vma); + mmap_read_unlock(mm); + + /* + * Check if access to the VMA is okay. + * We don't allow for stack expansion. + */ + acc_type = (insn & 0x40) ? VM_WRITE : VM_READ; + if (vma + && address >= vma->vm_start + && (vma->vm_flags & acc_type) == acc_type) + val = 1; + } + } + if (treg) + regs->gr[treg] = val; + regs->gr[0] |= PSW_N; + return 1; + + case 0x300: + /* LPA instruction */ + if (insn & 0x20) { + /* Base modification */ + breg = (insn >> 21) & 0x1f; + xreg = (insn >> 16) & 0x1f; + if (breg && xreg) + regs->gr[breg] += regs->gr[xreg]; + } + treg = insn & 0x1f; + if (treg) + regs->gr[treg] = 0; + regs->gr[0] |= PSW_N; + return 1; + + default: + break; + } + + return 0; +} diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c index 1ae31db9988f..1dc2e88e7b04 100644 --- a/arch/parisc/mm/init.c +++ b/arch/parisc/mm/init.c @@ -337,9 +337,9 @@ static void __init setup_bootmem(void) static bool kernel_set_to_readonly; -static void __init map_pages(unsigned long start_vaddr, - unsigned long start_paddr, unsigned long size, - pgprot_t pgprot, int force) +static void __ref map_pages(unsigned long start_vaddr, + unsigned long start_paddr, unsigned long size, + pgprot_t pgprot, int force) { pmd_t *pmd; pte_t *pg_table; @@ -449,7 +449,7 @@ void __init set_kernel_text_rw(int enable_read_write) flush_tlb_all(); } -void __ref free_initmem(void) +void free_initmem(void) { unsigned long init_begin = (unsigned long)__init_begin; unsigned long init_end = (unsigned long)__init_end; @@ -463,7 +463,6 @@ void __ref free_initmem(void) /* The init text pages are marked R-X. We have to * flush the icache and mark them RW- * - * This is tricky, because map_pages is in the init section. * Do a dummy remap of the data section first (the data * section is already PAGE_KERNEL) to pull in the TLB entries * for map_kernel */ |