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-rw-r--r--arch/s390/Kconfig8
-rw-r--r--arch/s390/Kconfig.debug4
-rw-r--r--arch/s390/Makefile5
-rw-r--r--arch/s390/kernel/Makefile1
-rw-r--r--arch/s390/kernel/entry.S29
-rw-r--r--arch/s390/kernel/entry64.S21
-rw-r--r--arch/s390/kernel/irq.c8
-rw-r--r--arch/s390/kernel/process.c1
-rw-r--r--arch/s390/kernel/stacktrace.c90
9 files changed, 158 insertions, 9 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 821a141889de..224fbff79969 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -7,6 +7,14 @@ config MMU
bool
default y
+config LOCKDEP_SUPPORT
+ bool
+ default y
+
+config STACKTRACE_SUPPORT
+ bool
+ default y
+
config RWSEM_GENERIC_SPINLOCK
bool
diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug
index f53b6d5300e5..2283933a9a93 100644
--- a/arch/s390/Kconfig.debug
+++ b/arch/s390/Kconfig.debug
@@ -1,5 +1,9 @@
menu "Kernel hacking"
+config TRACE_IRQFLAGS_SUPPORT
+ bool
+ default y
+
source "lib/Kconfig.debug"
endmenu
diff --git a/arch/s390/Makefile b/arch/s390/Makefile
index b3791fb094a8..74ef57dcfa60 100644
--- a/arch/s390/Makefile
+++ b/arch/s390/Makefile
@@ -34,6 +34,11 @@ cflags-$(CONFIG_MARCH_G5) += $(call cc-option,-march=g5)
cflags-$(CONFIG_MARCH_Z900) += $(call cc-option,-march=z900)
cflags-$(CONFIG_MARCH_Z990) += $(call cc-option,-march=z990)
+#
+# Prevent tail-call optimizations, to get clearer backtraces:
+#
+cflags-$(CONFIG_FRAME_POINTER) += -fno-optimize-sibling-calls
+
# old style option for packed stacks
ifeq ($(call cc-option-yn,-mkernel-backchain),y)
cflags-$(CONFIG_PACK_STACK) += -mkernel-backchain -D__PACK_STACK
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index 9269b5788fac..eabf00a6f770 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_COMPAT) += compat_linux.o compat_signal.o \
obj-$(CONFIG_BINFMT_ELF32) += binfmt_elf32.o
obj-$(CONFIG_VIRT_TIMER) += vtime.o
+obj-$(CONFIG_STACKTRACE) += stacktrace.o
# Kexec part
S390_KEXEC_OBJS := machine_kexec.o crash.o
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index d8948c342caf..5b5799ac8f83 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -58,6 +58,21 @@ STACK_SIZE = 1 << STACK_SHIFT
#define BASED(name) name-system_call(%r13)
+#ifdef CONFIG_TRACE_IRQFLAGS
+ .macro TRACE_IRQS_ON
+ l %r1,BASED(.Ltrace_irq_on)
+ basr %r14,%r1
+ .endm
+
+ .macro TRACE_IRQS_OFF
+ l %r1,BASED(.Ltrace_irq_off)
+ basr %r14,%r1
+ .endm
+#else
+#define TRACE_IRQS_ON
+#define TRACE_IRQS_OFF
+#endif
+
/*
* Register usage in interrupt handlers:
* R9 - pointer to current task structure
@@ -361,6 +376,7 @@ ret_from_fork:
st %r15,SP_R15(%r15) # store stack pointer for new kthread
0: l %r1,BASED(.Lschedtail)
basr %r14,%r1
+ TRACE_IRQS_ON
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
b BASED(sysc_return)
@@ -516,6 +532,7 @@ pgm_no_vtime3:
mvc __THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+ TRACE_IRQS_ON
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
b BASED(sysc_do_svc)
@@ -539,9 +556,11 @@ io_int_handler:
io_no_vtime:
#endif
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ TRACE_IRQS_OFF
l %r1,BASED(.Ldo_IRQ) # load address of do_IRQ
la %r2,SP_PTREGS(%r15) # address of register-save area
basr %r14,%r1 # branch to standard irq handler
+ TRACE_IRQS_ON
io_return:
tm SP_PSW+1(%r15),0x01 # returning to user ?
@@ -651,10 +670,12 @@ ext_int_handler:
ext_no_vtime:
#endif
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ TRACE_IRQS_OFF
la %r2,SP_PTREGS(%r15) # address of register-save area
lh %r3,__LC_EXT_INT_CODE # get interruption code
l %r1,BASED(.Ldo_extint)
basr %r14,%r1
+ TRACE_IRQS_ON
b BASED(io_return)
__critical_end:
@@ -731,8 +752,10 @@ mcck_no_vtime:
stosm __SF_EMPTY(%r15),0x04 # turn dat on
tm __TI_flags+3(%r9),_TIF_MCCK_PENDING
bno BASED(mcck_return)
+ TRACE_IRQS_OFF
l %r1,BASED(.Ls390_handle_mcck)
basr %r14,%r1 # call machine check handler
+ TRACE_IRQS_ON
mcck_return:
mvc __LC_RETURN_MCCK_PSW(8),SP_PSW(%r15) # move return PSW
ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
@@ -1012,7 +1035,11 @@ cleanup_io_leave_insn:
.Lvfork: .long sys_vfork
.Lschedtail: .long schedule_tail
.Lsysc_table: .long sys_call_table
-
+#ifdef CONFIG_TRACE_IRQFLAGS
+.Ltrace_irq_on:.long trace_hardirqs_on
+.Ltrace_irq_off:
+ .long trace_hardirqs_off
+#endif
.Lcritical_start:
.long __critical_start + 0x80000000
.Lcritical_end:
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 1ca499fa54b4..56f5f613b868 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -58,6 +58,19 @@ _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \
#define BASED(name) name-system_call(%r13)
+#ifdef CONFIG_TRACE_IRQFLAGS
+ .macro TRACE_IRQS_ON
+ brasl %r14,trace_hardirqs_on
+ .endm
+
+ .macro TRACE_IRQS_OFF
+ brasl %r14,trace_hardirqs_off
+ .endm
+#else
+#define TRACE_IRQS_ON
+#define TRACE_IRQS_OFF
+#endif
+
.macro STORE_TIMER lc_offset
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
stpt \lc_offset
@@ -354,6 +367,7 @@ ret_from_fork:
jo 0f
stg %r15,SP_R15(%r15) # store stack pointer for new kthread
0: brasl %r14,schedule_tail
+ TRACE_IRQS_ON
stosm 24(%r15),0x03 # reenable interrupts
j sysc_return
@@ -535,6 +549,7 @@ pgm_no_vtime3:
mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+ TRACE_IRQS_ON
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
j sysc_do_svc
@@ -557,8 +572,10 @@ io_int_handler:
io_no_vtime:
#endif
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ TRACE_IRQS_OFF
la %r2,SP_PTREGS(%r15) # address of register-save area
brasl %r14,do_IRQ # call standard irq handler
+ TRACE_IRQS_ON
io_return:
tm SP_PSW+1(%r15),0x01 # returning to user ?
@@ -665,9 +682,11 @@ ext_int_handler:
ext_no_vtime:
#endif
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ TRACE_IRQS_OFF
la %r2,SP_PTREGS(%r15) # address of register-save area
llgh %r3,__LC_EXT_INT_CODE # get interruption code
brasl %r14,do_extint
+ TRACE_IRQS_ON
j io_return
__critical_end:
@@ -743,7 +762,9 @@ mcck_no_vtime:
stosm __SF_EMPTY(%r15),0x04 # turn dat on
tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
jno mcck_return
+ TRACE_IRQS_OFF
brasl %r14,s390_handle_mcck
+ TRACE_IRQS_ON
mcck_return:
mvc __LC_RETURN_MCCK_PSW(16),SP_PSW(%r15) # move return PSW
ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index 480b6a5fef3a..1eef50918615 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -69,10 +69,6 @@ asmlinkage void do_softirq(void)
local_irq_save(flags);
- account_system_vtime(current);
-
- local_bh_disable();
-
if (local_softirq_pending()) {
/* Get current stack pointer. */
asm volatile("la %0,0(15)" : "=a" (old));
@@ -95,10 +91,6 @@ asmlinkage void do_softirq(void)
__do_softirq();
}
- account_system_vtime(current);
-
- __local_bh_enable();
-
local_irq_restore(flags);
}
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 1f9399191794..78c8e5548caf 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -142,6 +142,7 @@ static void default_idle(void)
return;
}
+ trace_hardirqs_on();
/* Wait for external, I/O or machine check interrupt. */
__load_psw_mask(PSW_KERNEL_BITS | PSW_MASK_WAIT |
PSW_MASK_IO | PSW_MASK_EXT);
diff --git a/arch/s390/kernel/stacktrace.c b/arch/s390/kernel/stacktrace.c
new file mode 100644
index 000000000000..de83f38288d0
--- /dev/null
+++ b/arch/s390/kernel/stacktrace.c
@@ -0,0 +1,90 @@
+/*
+ * arch/s390/kernel/stacktrace.c
+ *
+ * Stack trace management functions
+ *
+ * Copyright (C) IBM Corp. 2006
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <linux/kallsyms.h>
+
+static inline unsigned long save_context_stack(struct stack_trace *trace,
+ unsigned int *skip,
+ unsigned long sp,
+ unsigned long low,
+ unsigned long high)
+{
+ struct stack_frame *sf;
+ struct pt_regs *regs;
+ unsigned long addr;
+
+ while(1) {
+ sp &= PSW_ADDR_INSN;
+ if (sp < low || sp > high)
+ return sp;
+ sf = (struct stack_frame *)sp;
+ while(1) {
+ addr = sf->gprs[8] & PSW_ADDR_INSN;
+ if (!(*skip))
+ trace->entries[trace->nr_entries++] = addr;
+ else
+ (*skip)--;
+ if (trace->nr_entries >= trace->max_entries)
+ return sp;
+ low = sp;
+ sp = sf->back_chain & PSW_ADDR_INSN;
+ if (!sp)
+ break;
+ if (sp <= low || sp > high - sizeof(*sf))
+ return sp;
+ sf = (struct stack_frame *)sp;
+ }
+ /* Zero backchain detected, check for interrupt frame. */
+ sp = (unsigned long)(sf + 1);
+ if (sp <= low || sp > high - sizeof(*regs))
+ return sp;
+ regs = (struct pt_regs *)sp;
+ addr = regs->psw.addr & PSW_ADDR_INSN;
+ if (!(*skip))
+ trace->entries[trace->nr_entries++] = addr;
+ else
+ (*skip)--;
+ if (trace->nr_entries >= trace->max_entries)
+ return sp;
+ low = sp;
+ sp = regs->gprs[15];
+ }
+}
+
+void save_stack_trace(struct stack_trace *trace,
+ struct task_struct *task, int all_contexts,
+ unsigned int skip)
+{
+ register unsigned long sp asm ("15");
+ unsigned long orig_sp;
+
+ sp &= PSW_ADDR_INSN;
+ orig_sp = sp;
+
+ sp = save_context_stack(trace, &skip, sp,
+ S390_lowcore.panic_stack - PAGE_SIZE,
+ S390_lowcore.panic_stack);
+ if ((sp != orig_sp) && !all_contexts)
+ return;
+ sp = save_context_stack(trace, &skip, sp,
+ S390_lowcore.async_stack - ASYNC_SIZE,
+ S390_lowcore.async_stack);
+ if ((sp != orig_sp) && !all_contexts)
+ return;
+ if (task)
+ save_context_stack(trace, &skip, sp,
+ (unsigned long) task_stack_page(task),
+ (unsigned long) task_stack_page(task) + THREAD_SIZE);
+ else
+ save_context_stack(trace, &skip, sp, S390_lowcore.thread_info,
+ S390_lowcore.thread_info + THREAD_SIZE);
+ return;
+}