diff options
Diffstat (limited to 'arch/s390/mm/fault.c')
| -rw-r--r-- | arch/s390/mm/fault.c | 63 |
1 files changed, 44 insertions, 19 deletions
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index 9649d9382e0a..a2632fd97d00 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -46,11 +46,15 @@ #define __SUBCODE_MASK 0x0600 #define __PF_RES_FIELD 0x8000000000000000ULL -#define VM_FAULT_BADCONTEXT ((__force vm_fault_t) 0x010000) -#define VM_FAULT_BADMAP ((__force vm_fault_t) 0x020000) -#define VM_FAULT_BADACCESS ((__force vm_fault_t) 0x040000) -#define VM_FAULT_SIGNAL ((__force vm_fault_t) 0x080000) -#define VM_FAULT_PFAULT ((__force vm_fault_t) 0x100000) +/* + * Allocate private vm_fault_reason from top. Please make sure it won't + * collide with vm_fault_reason. + */ +#define VM_FAULT_BADCONTEXT ((__force vm_fault_t)0x80000000) +#define VM_FAULT_BADMAP ((__force vm_fault_t)0x40000000) +#define VM_FAULT_BADACCESS ((__force vm_fault_t)0x20000000) +#define VM_FAULT_SIGNAL ((__force vm_fault_t)0x10000000) +#define VM_FAULT_PFAULT ((__force vm_fault_t)0x8000000) enum fault_type { KERNEL_FAULT, @@ -96,6 +100,20 @@ static enum fault_type get_fault_type(struct pt_regs *regs) return KERNEL_FAULT; } +static unsigned long get_fault_address(struct pt_regs *regs) +{ + unsigned long trans_exc_code = regs->int_parm_long; + + return trans_exc_code & __FAIL_ADDR_MASK; +} + +static bool fault_is_write(struct pt_regs *regs) +{ + unsigned long trans_exc_code = regs->int_parm_long; + + return (trans_exc_code & store_indication) == 0x400; +} + static int bad_address(void *p) { unsigned long dummy; @@ -228,15 +246,26 @@ static noinline void do_sigsegv(struct pt_regs *regs, int si_code) (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK)); } -static noinline void do_no_context(struct pt_regs *regs) +static noinline void do_no_context(struct pt_regs *regs, vm_fault_t fault) { + enum fault_type fault_type; + unsigned long address; + bool is_write; + if (fixup_exception(regs)) return; + fault_type = get_fault_type(regs); + if ((fault_type == KERNEL_FAULT) && (fault == VM_FAULT_BADCONTEXT)) { + address = get_fault_address(regs); + is_write = fault_is_write(regs); + if (kfence_handle_page_fault(address, is_write, regs)) + return; + } /* * Oops. The kernel tried to access some bad page. We'll have to * terminate things with extreme prejudice. */ - if (get_fault_type(regs) == KERNEL_FAULT) + if (fault_type == KERNEL_FAULT) printk(KERN_ALERT "Unable to handle kernel pointer dereference" " in virtual kernel address space\n"); else @@ -255,7 +284,7 @@ static noinline void do_low_address(struct pt_regs *regs) die (regs, "Low-address protection"); } - do_no_context(regs); + do_no_context(regs, VM_FAULT_BADACCESS); } static noinline void do_sigbus(struct pt_regs *regs) @@ -286,28 +315,28 @@ static noinline void do_fault_error(struct pt_regs *regs, vm_fault_t fault) fallthrough; case VM_FAULT_BADCONTEXT: case VM_FAULT_PFAULT: - do_no_context(regs); + do_no_context(regs, fault); break; case VM_FAULT_SIGNAL: if (!user_mode(regs)) - do_no_context(regs); + do_no_context(regs, fault); break; default: /* fault & VM_FAULT_ERROR */ if (fault & VM_FAULT_OOM) { if (!user_mode(regs)) - do_no_context(regs); + do_no_context(regs, fault); else pagefault_out_of_memory(); } else if (fault & VM_FAULT_SIGSEGV) { /* Kernel mode? Handle exceptions or die */ if (!user_mode(regs)) - do_no_context(regs); + do_no_context(regs, fault); else do_sigsegv(regs, SEGV_MAPERR); } else if (fault & VM_FAULT_SIGBUS) { /* Kernel mode? Handle exceptions or die */ if (!user_mode(regs)) - do_no_context(regs); + do_no_context(regs, fault); else do_sigbus(regs); } else @@ -334,7 +363,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access) struct mm_struct *mm; struct vm_area_struct *vma; enum fault_type type; - unsigned long trans_exc_code; unsigned long address; unsigned int flags; vm_fault_t fault; @@ -351,9 +379,8 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access) return 0; mm = tsk->mm; - trans_exc_code = regs->int_parm_long; - address = trans_exc_code & __FAIL_ADDR_MASK; - is_write = (trans_exc_code & store_indication) == 0x400; + address = get_fault_address(regs); + is_write = fault_is_write(regs); /* * Verify that the fault happened in user space, that @@ -364,8 +391,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access) type = get_fault_type(regs); switch (type) { case KERNEL_FAULT: - if (kfence_handle_page_fault(address, is_write, regs)) - return 0; goto out; case USER_FAULT: case GMAP_FAULT: |