diff options
Diffstat (limited to 'arch/powerpc/mm/fault.c')
| -rw-r--r-- | arch/powerpc/mm/fault.c | 53 |
1 files changed, 45 insertions, 8 deletions
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 6e1e39035380..866446cf2d9a 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -107,7 +107,8 @@ static bool store_updates_sp(struct pt_regs *regs) */ static int -__bad_area_nosemaphore(struct pt_regs *regs, unsigned long address, int si_code) +__bad_area_nosemaphore(struct pt_regs *regs, unsigned long address, int si_code, + int pkey) { /* * If we are in kernel mode, bail out with a SEGV, this will @@ -117,17 +118,18 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long address, int si_code) if (!user_mode(regs)) return SIGSEGV; - _exception(SIGSEGV, regs, si_code, address); + _exception_pkey(SIGSEGV, regs, si_code, address, pkey); return 0; } static noinline int bad_area_nosemaphore(struct pt_regs *regs, unsigned long address) { - return __bad_area_nosemaphore(regs, address, SEGV_MAPERR); + return __bad_area_nosemaphore(regs, address, SEGV_MAPERR, 0); } -static int __bad_area(struct pt_regs *regs, unsigned long address, int si_code) +static int __bad_area(struct pt_regs *regs, unsigned long address, int si_code, + int pkey) { struct mm_struct *mm = current->mm; @@ -137,17 +139,23 @@ static int __bad_area(struct pt_regs *regs, unsigned long address, int si_code) */ up_read(&mm->mmap_sem); - return __bad_area_nosemaphore(regs, address, si_code); + return __bad_area_nosemaphore(regs, address, si_code, pkey); } static noinline int bad_area(struct pt_regs *regs, unsigned long address) { - return __bad_area(regs, address, SEGV_MAPERR); + return __bad_area(regs, address, SEGV_MAPERR, 0); +} + +static int bad_key_fault_exception(struct pt_regs *regs, unsigned long address, + int pkey) +{ + return __bad_area_nosemaphore(regs, address, SEGV_PKUERR, pkey); } static noinline int bad_access(struct pt_regs *regs, unsigned long address) { - return __bad_area(regs, address, SEGV_ACCERR); + return __bad_area(regs, address, SEGV_ACCERR, 0); } static int do_sigbus(struct pt_regs *regs, unsigned long address, @@ -432,6 +440,10 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); + if (error_code & DSISR_KEYFAULT) + return bad_key_fault_exception(regs, address, + get_mm_addr_key(mm, address)); + /* * We want to do this outside mmap_sem, because reading code around nip * can result in fault, which will cause a deadlock when called with @@ -503,6 +515,31 @@ good_area: * the fault. */ fault = handle_mm_fault(vma, address, flags); + +#ifdef CONFIG_PPC_MEM_KEYS + /* + * if the HPTE is not hashed, hardware will not detect + * a key fault. Lets check if we failed because of a + * software detected key fault. + */ + if (unlikely(fault & VM_FAULT_SIGSEGV) && + !arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE, + is_exec, 0)) { + /* + * The PGD-PDT...PMD-PTE tree may not have been fully setup. + * Hence we cannot walk the tree to locate the PTE, to locate + * the key. Hence let's use vma_pkey() to get the key; instead + * of get_mm_addr_key(). + */ + int pkey = vma_pkey(vma); + + if (likely(pkey)) { + up_read(&mm->mmap_sem); + return bad_key_fault_exception(regs, address, pkey); + } + } +#endif /* CONFIG_PPC_MEM_KEYS */ + major |= fault & VM_FAULT_MAJOR; /* @@ -576,7 +613,7 @@ void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig) /* kernel has accessed a bad area */ - switch (regs->trap) { + switch (TRAP(regs)) { case 0x300: case 0x380: printk(KERN_ALERT "Unable to handle kernel paging request for " |