diff options
| -rw-r--r-- | arch/s390/include/asm/processor.h | 42 | ||||
| -rw-r--r-- | arch/s390/include/asm/uaccess.h | 15 | ||||
| -rw-r--r-- | arch/s390/kernel/early.c | 4 | ||||
| -rw-r--r-- | arch/s390/kernel/entry64.S | 5 | ||||
| -rw-r--r-- | arch/s390/kernel/kprobes.c | 2 | ||||
| -rw-r--r-- | arch/s390/kernel/traps.c | 2 | ||||
| -rw-r--r-- | arch/s390/mm/Makefile | 2 | ||||
| -rw-r--r-- | arch/s390/mm/extable.c | 81 | ||||
| -rw-r--r-- | arch/s390/mm/fault.c | 2 | ||||
| -rw-r--r-- | scripts/sortextable.c | 10 |
10 files changed, 132 insertions, 33 deletions
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index 7e81ff17a89b..f3e0aabfc6bc 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -11,6 +11,8 @@ #ifndef __ASM_S390_PROCESSOR_H #define __ASM_S390_PROCESSOR_H +#ifndef __ASSEMBLY__ + #include <linux/linkage.h> #include <linux/irqflags.h> #include <asm/cpu.h> @@ -348,23 +350,6 @@ extern void (*s390_base_ext_handler_fn)(void); #define ARCH_LOW_ADDRESS_LIMIT 0x7fffffffUL -/* - * Helper macro for exception table entries - */ -#ifndef CONFIG_64BIT -#define EX_TABLE(_fault,_target) \ - ".section __ex_table,\"a\"\n" \ - " .align 4\n" \ - " .long " #_fault "," #_target "\n" \ - ".previous\n" -#else -#define EX_TABLE(_fault,_target) \ - ".section __ex_table,\"a\"\n" \ - " .align 8\n" \ - " .quad " #_fault "," #_target "\n" \ - ".previous\n" -#endif - extern int memcpy_real(void *, void *, size_t); extern void memcpy_absolute(void *, void *, size_t); @@ -375,4 +360,25 @@ extern void memcpy_absolute(void *, void *, size_t); memcpy_absolute(&(dest), &__tmp, sizeof(__tmp)); \ } -#endif /* __ASM_S390_PROCESSOR_H */ +/* + * Helper macro for exception table entries + */ +#define EX_TABLE(_fault, _target) \ + ".section __ex_table,\"a\"\n" \ + ".align 4\n" \ + ".long (" #_fault ") - .\n" \ + ".long (" #_target ") - .\n" \ + ".previous\n" + +#else /* __ASSEMBLY__ */ + +#define EX_TABLE(_fault, _target) \ + .section __ex_table,"a" ; \ + .align 4 ; \ + .long (_fault) - . ; \ + .long (_target) - . ; \ + .previous + +#endif /* __ASSEMBLY__ */ + +#endif /* __ASM_S390_PROCESSOR_H */ diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h index a8ab18b18b54..34268df959a3 100644 --- a/arch/s390/include/asm/uaccess.h +++ b/arch/s390/include/asm/uaccess.h @@ -76,9 +76,22 @@ static inline int __range_ok(unsigned long addr, unsigned long size) struct exception_table_entry { - unsigned long insn, fixup; + int insn, fixup; }; +static inline unsigned long extable_insn(const struct exception_table_entry *x) +{ + return (unsigned long)&x->insn + x->insn; +} + +static inline unsigned long extable_fixup(const struct exception_table_entry *x) +{ + return (unsigned long)&x->fixup + x->fixup; +} + +#define ARCH_HAS_SORT_EXTABLE +#define ARCH_HAS_SEARCH_EXTABLE + struct uaccess_ops { size_t (*copy_from_user)(size_t, const void __user *, void *); size_t (*copy_from_user_small)(size_t, const void __user *, void *); diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index f4bcdc01bfc8..e8000d5ff533 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -255,14 +255,14 @@ static __init void setup_topology(void) static void early_pgm_check_handler(void) { - unsigned long addr; const struct exception_table_entry *fixup; + unsigned long addr; addr = S390_lowcore.program_old_psw.addr; fixup = search_exception_tables(addr & PSW_ADDR_INSN); if (!fixup) disabled_wait(0); - S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE; + S390_lowcore.program_old_psw.addr = extable_fixup(fixup)|PSW_ADDR_AMODE; } static noinline __init void setup_lowcore_early(void) diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index 95e9d93d4f41..7549985402f7 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -10,6 +10,7 @@ #include <linux/init.h> #include <linux/linkage.h> +#include <asm/processor.h> #include <asm/cache.h> #include <asm/errno.h> #include <asm/ptrace.h> @@ -1008,9 +1009,7 @@ sie_fault: .Lhost_id: .quad 0 - .section __ex_table,"a" - .quad sie_loop,sie_fault - .previous + EX_TABLE(sie_loop,sie_fault) #endif .section .rodata, "a" diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c index 8aa634f5944b..d1c7214e157c 100644 --- a/arch/s390/kernel/kprobes.c +++ b/arch/s390/kernel/kprobes.c @@ -547,7 +547,7 @@ static int __kprobes kprobe_trap_handler(struct pt_regs *regs, int trapnr) */ entry = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN); if (entry) { - regs->psw.addr = entry->fixup | PSW_ADDR_AMODE; + regs->psw.addr = extable_fixup(entry) | PSW_ADDR_AMODE; return 1; } diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c index 29af52628e8b..befc761fc154 100644 --- a/arch/s390/kernel/traps.c +++ b/arch/s390/kernel/traps.c @@ -322,7 +322,7 @@ static void __kprobes do_trap(struct pt_regs *regs, const struct exception_table_entry *fixup; fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN); if (fixup) - regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE; + regs->psw.addr = extable_fixup(fixup) | PSW_ADDR_AMODE; else { enum bug_trap_type btt; diff --git a/arch/s390/mm/Makefile b/arch/s390/mm/Makefile index d98fe9004a52..0f5536b0c1a1 100644 --- a/arch/s390/mm/Makefile +++ b/arch/s390/mm/Makefile @@ -3,7 +3,7 @@ # obj-y := init.o fault.o extmem.o mmap.o vmem.o pgtable.o maccess.o \ - page-states.o gup.o + page-states.o gup.o extable.o obj-$(CONFIG_CMM) += cmm.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o obj-$(CONFIG_DEBUG_SET_MODULE_RONX) += pageattr.o diff --git a/arch/s390/mm/extable.c b/arch/s390/mm/extable.c new file mode 100644 index 000000000000..4d1ee88864e8 --- /dev/null +++ b/arch/s390/mm/extable.c @@ -0,0 +1,81 @@ +#include <linux/module.h> +#include <linux/sort.h> +#include <asm/uaccess.h> + +/* + * Search one exception table for an entry corresponding to the + * given instruction address, and return the address of the entry, + * or NULL if none is found. + * We use a binary search, and thus we assume that the table is + * already sorted. + */ +const struct exception_table_entry * +search_extable(const struct exception_table_entry *first, + const struct exception_table_entry *last, + unsigned long value) +{ + const struct exception_table_entry *mid; + unsigned long addr; + + while (first <= last) { + mid = ((last - first) >> 1) + first; + addr = extable_insn(mid); + if (addr < value) + first = mid + 1; + else if (addr > value) + last = mid - 1; + else + return mid; + } + return NULL; +} + +/* + * The exception table needs to be sorted so that the binary + * search that we use to find entries in it works properly. + * This is used both for the kernel exception table and for + * the exception tables of modules that get loaded. + * + */ +static int cmp_ex(const void *a, const void *b) +{ + const struct exception_table_entry *x = a, *y = b; + + /* This compare is only valid after normalization. */ + return x->insn - y->insn; +} + +void sort_extable(struct exception_table_entry *start, + struct exception_table_entry *finish) +{ + struct exception_table_entry *p; + int i; + + /* Normalize entries to being relative to the start of the section */ + for (p = start, i = 0; p < finish; p++, i += 8) + p->insn += i; + sort(start, finish - start, sizeof(*start), cmp_ex, NULL); + /* Denormalize all entries */ + for (p = start, i = 0; p < finish; p++, i += 8) + p->insn -= i; +} + +#ifdef CONFIG_MODULES +/* + * If the exception table is sorted, any referring to the module init + * will be at the beginning or the end. + */ +void trim_init_extable(struct module *m) +{ + /* Trim the beginning */ + while (m->num_exentries && + within_module_init(extable_insn(&m->extable[0]), m)) { + m->extable++; + m->num_exentries--; + } + /* Trim the end */ + while (m->num_exentries && + within_module_init(extable_insn(&m->extable[m->num_exentries-1]), m)) + m->num_exentries--; +} +#endif /* CONFIG_MODULES */ diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index 8b2cac1ddbc5..ac9122ca1152 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -163,7 +163,7 @@ static noinline void do_no_context(struct pt_regs *regs) /* Are we prepared to handle this kernel fault? */ fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN); if (fixup) { - regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE; + regs->psw.addr = extable_fixup(fixup) | PSW_ADDR_AMODE; return; } diff --git a/scripts/sortextable.c b/scripts/sortextable.c index 6acf83449105..f19ddc47304c 100644 --- a/scripts/sortextable.c +++ b/scripts/sortextable.c @@ -161,7 +161,7 @@ typedef void (*table_sort_t)(char *, int); #define SORTEXTABLE_64 #include "sortextable.h" -static int compare_x86_table(const void *a, const void *b) +static int compare_relative_table(const void *a, const void *b) { int32_t av = (int32_t)r(a); int32_t bv = (int32_t)r(b); @@ -173,7 +173,7 @@ static int compare_x86_table(const void *a, const void *b) return 0; } -static void sort_x86_table(char *extab_image, int image_size) +static void sort_relative_table(char *extab_image, int image_size) { int i; @@ -188,7 +188,7 @@ static void sort_x86_table(char *extab_image, int image_size) i += 4; } - qsort(extab_image, image_size / 8, 8, compare_x86_table); + qsort(extab_image, image_size / 8, 8, compare_relative_table); /* Now denormalize. */ i = 0; @@ -245,9 +245,9 @@ do_file(char const *const fname) break; case EM_386: case EM_X86_64: - custom_sort = sort_x86_table; - break; case EM_S390: + custom_sort = sort_relative_table; + break; case EM_MIPS: break; } /* end switch */ |