diff options
Diffstat (limited to 'arch/s390/kernel')
| -rw-r--r-- | arch/s390/kernel/Makefile | 11 | ||||
| -rw-r--r-- | arch/s390/kernel/als.c | 124 | ||||
| -rw-r--r-- | arch/s390/kernel/entry.h | 2 | ||||
| -rw-r--r-- | arch/s390/kernel/head.S | 43 | ||||
| -rw-r--r-- | arch/s390/kernel/kprobes.c | 12 | ||||
| -rw-r--r-- | arch/s390/kernel/sclp.c | 5 |
6 files changed, 153 insertions, 44 deletions
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile index f37be37edd3a..3234817c7d47 100644 --- a/arch/s390/kernel/Makefile +++ b/arch/s390/kernel/Makefile @@ -4,6 +4,7 @@ KCOV_INSTRUMENT_early.o := n KCOV_INSTRUMENT_sclp.o := n +KCOV_INSTRUMENT_als.o := n ifdef CONFIG_FUNCTION_TRACER # Don't trace early setup code and tracing code @@ -32,21 +33,25 @@ CFLAGS_ptrace.o += -DUTS_MACHINE='"$(UTS_MACHINE)"' CFLAGS_sysinfo.o += -w # -# Use -march=z900 for sclp.c to be able to print an error message if -# the kernel is started on a machine which is too old +# Use -march=z900 for sclp.c and als.c to be able to print an error +# message if the kernel is started on a machine which is too old # CFLAGS_REMOVE_sclp.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_als.o = $(CC_FLAGS_FTRACE) ifneq ($(CC_FLAGS_MARCH),-march=z900) CFLAGS_REMOVE_sclp.o += $(CC_FLAGS_MARCH) CFLAGS_sclp.o += -march=z900 +CFLAGS_REMOVE_als.o += $(CC_FLAGS_MARCH) +CFLAGS_als.o += -march=z900 AFLAGS_REMOVE_head.o += $(CC_FLAGS_MARCH) AFLAGS_head.o += -march=z900 endif GCOV_PROFILE_sclp.o := n +GCOV_PROFILE_als.o := n obj-y := traps.o time.o process.o base.o early.o setup.o idle.o vtime.o obj-y += processor.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o nmi.o -obj-y += debug.o irq.o ipl.o dis.o diag.o sclp.o vdso.o +obj-y += debug.o irq.o ipl.o dis.o diag.o sclp.o vdso.o als.o obj-y += sysinfo.o jump_label.o lgr.o os_info.o machine_kexec.o pgm_check.o obj-y += runtime_instr.o cache.o fpu.o dumpstack.o obj-y += entry.o reipl.o relocate_kernel.o diff --git a/arch/s390/kernel/als.c b/arch/s390/kernel/als.c new file mode 100644 index 000000000000..a16e9d1bf9e3 --- /dev/null +++ b/arch/s390/kernel/als.c @@ -0,0 +1,124 @@ +/* + * Copyright IBM Corp. 2016 + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <asm/processor.h> +#include <asm/facility.h> +#include <asm/lowcore.h> +#include <asm/sclp.h> +#include "entry.h" + +/* + * The code within this file will be called very early. It may _not_ + * access anything within the bss section, since that is not cleared + * yet and may contain data (e.g. initrd) that must be saved by other + * code. + * For temporary objects the stack (16k) should be used. + */ + +static unsigned long als[] __initdata = { FACILITIES_ALS }; + +static void __init u16_to_hex(char *str, u16 val) +{ + int i, num; + + for (i = 1; i <= 4; i++) { + num = (val >> (16 - 4 * i)) & 0xf; + if (num >= 10) + num += 7; + *str++ = '0' + num; + } + *str = '\0'; +} + +static void __init print_machine_type(void) +{ + static char mach_str[80] __initdata = "Detected machine-type number: "; + char type_str[5]; + struct cpuid id; + + get_cpu_id(&id); + u16_to_hex(type_str, id.machine); + strcat(mach_str, type_str); + _sclp_print_early(mach_str); +} + +static void __init u16_to_decimal(char *str, u16 val) +{ + int div = 1; + + while (div * 10 <= val) + div *= 10; + while (div) { + *str++ = '0' + val / div; + val %= div; + div /= 10; + } + *str = '\0'; +} + +static void __init print_missing_facilities(void) +{ + static char als_str[80] __initdata = "Missing facilities: "; + unsigned long val; + char val_str[6]; + int i, j, first; + + first = 1; + for (i = 0; i < ARRAY_SIZE(als); i++) { + val = ~S390_lowcore.stfle_fac_list[i] & als[i]; + for (j = 0; j < BITS_PER_LONG; j++) { + if (!(val & (1UL << (BITS_PER_LONG - 1 - j)))) + continue; + if (!first) + strcat(als_str, ","); + /* + * Make sure we stay within one line. Consider that + * each facility bit adds up to five characters and + * z/VM adds a four character prefix. + */ + if (strlen(als_str) > 70) { + _sclp_print_early(als_str); + *als_str = '\0'; + } + u16_to_decimal(val_str, i * BITS_PER_LONG + j); + strcat(als_str, val_str); + first = 0; + } + } + _sclp_print_early(als_str); + _sclp_print_early("See Principles of Operations for facility bits"); +} + +static void __init facility_mismatch(void) +{ + _sclp_print_early("The Linux kernel requires more recent processor hardware"); + print_machine_type(); + print_missing_facilities(); + disabled_wait(0x8badcccc); +} + +void __init verify_facilities(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(S390_lowcore.stfle_fac_list); i++) + S390_lowcore.stfle_fac_list[i] = 0; + asm volatile( + " stfl 0(0)\n" + : "=m" (S390_lowcore.stfl_fac_list)); + S390_lowcore.stfle_fac_list[0] = (u64)S390_lowcore.stfl_fac_list << 32; + if (S390_lowcore.stfl_fac_list & 0x01000000) { + register unsigned long reg0 asm("0") = ARRAY_SIZE(als) - 1; + + asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */ + : "+d" (reg0) + : "a" (&S390_lowcore.stfle_fac_list) + : "memory", "cc"); + } + for (i = 0; i < ARRAY_SIZE(als); i++) { + if ((S390_lowcore.stfle_fac_list[i] & als[i]) != als[i]) + facility_mismatch(); + } +} diff --git a/arch/s390/kernel/entry.h b/arch/s390/kernel/entry.h index bedd2f55d860..e79f030dd276 100644 --- a/arch/s390/kernel/entry.h +++ b/arch/s390/kernel/entry.h @@ -79,4 +79,6 @@ long sys_s390_pci_mmio_read(unsigned long, void __user *, size_t); DECLARE_PER_CPU(u64, mt_cycles[8]); +void verify_facilities(void); + #endif /* _ENTRY_H */ diff --git a/arch/s390/kernel/head.S b/arch/s390/kernel/head.S index fcaefb041364..56e4d8234ef2 100644 --- a/arch/s390/kernel/head.S +++ b/arch/s390/kernel/head.S @@ -306,49 +306,14 @@ ENTRY(startup_kdump) stck __LC_LAST_UPDATE_CLOCK spt 6f-.LPG0(%r13) mvc __LC_LAST_UPDATE_TIMER(8),6f-.LPG0(%r13) - stfl 0(%r0) # store facilities @ __LC_STFL_FAC_LIST - mvc __LC_STFLE_FAC_LIST(4),__LC_STFL_FAC_LIST - tm __LC_STFLE_FAC_LIST,0x01 # stfle available ? - jz 0f - lghi %r0,FACILITIES_ALS_DWORDS-1 - .insn s,0xb2b00000,__LC_STFLE_FAC_LIST # store facility list extended - # verify if all required facilities are supported by the machine -0: la %r1,__LC_STFLE_FAC_LIST - la %r2,3f+8-.LPG0(%r13) - lhi %r3,FACILITIES_ALS_DWORDS -1: lg %r0,0(%r1) - ng %r0,0(%r2) - clg %r0,0(%r2) - jne 2f - la %r1,8(%r1) - la %r2,8(%r2) - ahi %r3,-1 - jnz 1b - j 4f -2: l %r15,.Lstack-.LPG0(%r13) + l %r15,.Lstack-.LPG0(%r13) ahi %r15,-STACK_FRAME_OVERHEAD - la %r2,.Lals_string-.LPG0(%r13) - l %r3,.Lsclp_print-.LPG0(%r13) - basr %r14,%r3 - lpsw 3f-.LPG0(%r13) # machine type not good enough, crash -.Lals_string: - .asciz "The Linux kernel requires more recent processor hardware" -.Lsclp_print: - .long _sclp_print_early -.Lstack: - .long 0x8000 + (1<<(PAGE_SHIFT+THREAD_ORDER)) - .align 16 -3: .long 0x000a0000,0x8badcccc - -# List of facilities that are required. If not all facilities are present -# the kernel will crash. - - .quad FACILITIES_ALS - -4: + brasl %r14,verify_facilities /* Continue with startup code in head64.S */ jg startup_continue +.Lstack: + .long 0x8000 + (1<<(PAGE_SHIFT+THREAD_ORDER)) .align 8 6: .long 0x7fffffff,0xffffffff diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c index 250f5972536a..dd6306c51bd6 100644 --- a/arch/s390/kernel/kprobes.c +++ b/arch/s390/kernel/kprobes.c @@ -690,6 +690,15 @@ int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) stack = (unsigned long) regs->gprs[15]; memcpy(kcb->jprobes_stack, (void *) stack, MIN_STACK_SIZE(stack)); + + /* + * jprobes use jprobe_return() which skips the normal return + * path of the function, and this messes up the accounting of the + * function graph tracer to get messed up. + * + * Pause function graph tracing while performing the jprobe function. + */ + pause_graph_tracing(); return 1; } NOKPROBE_SYMBOL(setjmp_pre_handler); @@ -705,6 +714,9 @@ int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); unsigned long stack; + /* It's OK to start function graph tracing again */ + unpause_graph_tracing(); + stack = (unsigned long) kcb->jprobe_saved_regs.gprs[15]; /* Put the regs back */ diff --git a/arch/s390/kernel/sclp.c b/arch/s390/kernel/sclp.c index d88db40bdf15..f08af675f36f 100644 --- a/arch/s390/kernel/sclp.c +++ b/arch/s390/kernel/sclp.c @@ -12,8 +12,9 @@ #define EVTYP_VT220MSG_MASK 0x00000040 #define EVTYP_MSG_MASK 0x40000000 -static char _sclp_work_area[4096] __aligned(PAGE_SIZE); -static bool have_vt220, have_linemode; +static char _sclp_work_area[4096] __aligned(PAGE_SIZE) __section(data); +static bool have_vt220 __section(data); +static bool have_linemode __section(data); static void _sclp_wait_int(void) { |