diff options
| -rw-r--r-- | arch/um/kernel/trap_kern.c | 28 |
1 files changed, 13 insertions, 15 deletions
diff --git a/arch/um/kernel/trap_kern.c b/arch/um/kernel/trap_kern.c index bef8abd5ea9..b5fc89fe9ea 100644 --- a/arch/um/kernel/trap_kern.c +++ b/arch/um/kernel/trap_kern.c @@ -26,6 +26,7 @@ #include "mem.h" #include "mem_kern.h" +/* Note this is constrained to return 0, -EFAULT, -EACCESS, -ENOMEM by segv(). */ int handle_page_fault(unsigned long address, unsigned long ip, int is_write, int is_user, int *code_out) { @@ -35,7 +36,6 @@ int handle_page_fault(unsigned long address, unsigned long ip, pud_t *pud; pmd_t *pmd; pte_t *pte; - unsigned long page; int err = -EFAULT; *code_out = SEGV_MAPERR; @@ -52,7 +52,7 @@ int handle_page_fault(unsigned long address, unsigned long ip, else if(expand_stack(vma, address)) goto out; - good_area: +good_area: *code_out = SEGV_ACCERR; if(is_write && !(vma->vm_flags & VM_WRITE)) goto out; @@ -60,9 +60,8 @@ int handle_page_fault(unsigned long address, unsigned long ip, if(!(vma->vm_flags & (VM_READ | VM_EXEC))) goto out; - page = address & PAGE_MASK; do { - survive: +survive: switch (handle_mm_fault(mm, vma, address, is_write)){ case VM_FAULT_MINOR: current->min_flt++; @@ -79,16 +78,16 @@ int handle_page_fault(unsigned long address, unsigned long ip, default: BUG(); } - pgd = pgd_offset(mm, page); - pud = pud_offset(pgd, page); - pmd = pmd_offset(pud, page); - pte = pte_offset_kernel(pmd, page); + pgd = pgd_offset(mm, address); + pud = pud_offset(pgd, address); + pmd = pmd_offset(pud, address); + pte = pte_offset_kernel(pmd, address); } while(!pte_present(*pte)); err = 0; *pte = pte_mkyoung(*pte); if(pte_write(*pte)) *pte = pte_mkdirty(*pte); - flush_tlb_page(vma, page); - out: + flush_tlb_page(vma, address); +out: up_read(&mm->mmap_sem); return(err); @@ -144,19 +143,18 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc) panic("Kernel mode fault at addr 0x%lx, ip 0x%lx", address, ip); - if(err == -EACCES){ + if (err == -EACCES) { si.si_signo = SIGBUS; si.si_errno = 0; si.si_code = BUS_ADRERR; si.si_addr = (void *)address; current->thread.arch.faultinfo = fi; force_sig_info(SIGBUS, &si, current); - } - else if(err == -ENOMEM){ + } else if (err == -ENOMEM) { printk("VM: killing process %s\n", current->comm); do_exit(SIGKILL); - } - else { + } else { + BUG_ON(err != -EFAULT); si.si_signo = SIGSEGV; si.si_addr = (void *) address; current->thread.arch.faultinfo = fi; |