diff options
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/kernel/early.c | 1 | ||||
| -rw-r--r-- | arch/s390/kernel/kprobes.c | 27 | ||||
| -rw-r--r-- | arch/s390/kernel/vmlinux.lds.S | 3 | ||||
| -rw-r--r-- | arch/s390/mm/init.c | 9 |
4 files changed, 29 insertions, 11 deletions
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index 40dd47970a3..e518dd53eff 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -27,7 +27,6 @@ #define DEFSYS_CMD_SIZE 96 #define SAVESYS_CMD_SIZE 32 -extern int _eshared; char kernel_nss_name[NSS_NAME_SIZE + 1]; #ifdef CONFIG_SHARED_KERNEL diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c index b2e1dc89a8c..a466bab6677 100644 --- a/arch/s390/kernel/kprobes.c +++ b/arch/s390/kernel/kprobes.c @@ -155,15 +155,34 @@ void __kprobes get_instruction_type(struct arch_specific_insn *ainsn) static int __kprobes swap_instruction(void *aref) { struct ins_replace_args *args = aref; + u32 *addr; + u32 instr; int err = -EFAULT; + /* + * Text segment is read-only, hence we use stura to bypass dynamic + * address translation to exchange the instruction. Since stura + * always operates on four bytes, but we only want to exchange two + * bytes do some calculations to get things right. In addition we + * shall not cross any page boundaries (vmalloc area!) when writing + * the new instruction. + */ + addr = (u32 *)ALIGN((unsigned long)args->ptr, 4); + if ((unsigned long)args->ptr & 2) + instr = ((*addr) & 0xffff0000) | args->new; + else + instr = ((*addr) & 0x0000ffff) | args->new << 16; + asm volatile( - "0: mvc 0(2,%2),0(%3)\n" - "1: la %0,0\n" + " lra %1,0(%1)\n" + "0: stura %2,%1\n" + "1: la %0,0\n" "2:\n" EX_TABLE(0b,2b) - : "+d" (err), "=m" (*args->ptr) - : "a" (args->ptr), "a" (&args->new), "m" (args->new)); + : "+d" (err) + : "a" (addr), "d" (instr) + : "memory", "cc"); + return err; } diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S index 8fedb1f9fc9..a4890739252 100644 --- a/arch/s390/kernel/vmlinux.lds.S +++ b/arch/s390/kernel/vmlinux.lds.S @@ -35,9 +35,10 @@ SECTIONS #ifdef CONFIG_SHARED_KERNEL . = ALIGN(1048576); /* VM shared segments are 1MB aligned */ +#endif + . = ALIGN(4096); _eshared = .; /* End of shareable data */ -#endif . = ALIGN(16); /* Exception table */ __start___ex_table = .; diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 162a338a557..b3e7c45efb6 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -26,7 +26,6 @@ #include <linux/pfn.h> #include <linux/poison.h> #include <linux/initrd.h> - #include <asm/processor.h> #include <asm/system.h> #include <asm/uaccess.h> @@ -96,8 +95,8 @@ static void __init setup_ro_region(void) pte_t new_pte; unsigned long address, end; - address = ((unsigned long)&__start_rodata) & PAGE_MASK; - end = PFN_ALIGN((unsigned long)&__end_rodata); + address = ((unsigned long)&_stext) & PAGE_MASK; + end = PFN_ALIGN((unsigned long)&_eshared); for (; address < end; address += PAGE_SIZE) { pgd = pgd_offset_k(address); @@ -173,8 +172,8 @@ void __init mem_init(void) datasize >>10, initsize >> 10); printk("Write protected kernel read-only data: %#lx - %#lx\n", - (unsigned long)&__start_rodata, - PFN_ALIGN((unsigned long)&__end_rodata) - 1); + (unsigned long)&_stext, + PFN_ALIGN((unsigned long)&_eshared) - 1); } void free_initmem(void) |