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authorLinus Torvalds2016-02-19 08:33:12 -0800
committerLinus Torvalds2016-02-19 08:33:12 -0800
commitff5f16820f632079d5095884adc5d71ee3249fa4 (patch)
tree5f474546110a3c7c3194264978304d268a716840 /arch
parent409ee136f28f71cbec518cfc85a379a508ccbaa0 (diff)
parent12d319b920fa673a4d5e7c1785c5dc82dcd15257 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Martin Schwidefsky: "Several bug fixes: - There are four different stack tracers, and three of them have bugs. For 4.5 the bugs are fixed and we prepare a cleanup patch for the next merge window. - Three bug fixes for the dasd driver in regard to parallel access volumes and the new max_dev_sectors block device queue limit - The irq restore optimization needs a fixup for memcpy_real - The diagnose trace code has a conflict with lockdep" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/dasd: fix performance drop s390/maccess: reduce stnsm instructions s390/diag: avoid lockdep recursion s390/dasd: fix refcount for PAV reassignment s390/dasd: prevent incorrect length error under z/VM after PAV changes s390: fix DAT off memory access, e.g. on kdump s390/oprofile: fix address range for asynchronous stack s390/perf_event: fix address range for asynchronous stack s390/stacktrace: add save_stack_trace_regs() s390/stacktrace: save full stack traces s390/stacktrace: add missing end marker s390/stacktrace: fix address ranges for asynchronous and panic stack s390/stacktrace: fix save_stack_trace_tsk() for current task
Diffstat (limited to 'arch')
-rw-r--r--arch/s390/kernel/perf_event.c8
-rw-r--r--arch/s390/kernel/stacktrace.c47
-rw-r--r--arch/s390/kernel/trace.c3
-rw-r--r--arch/s390/mm/maccess.c12
-rw-r--r--arch/s390/oprofile/backtrace.c8
5 files changed, 55 insertions, 23 deletions
diff --git a/arch/s390/kernel/perf_event.c b/arch/s390/kernel/perf_event.c
index cfcba2dd9bb5..0943b11a2f6e 100644
--- a/arch/s390/kernel/perf_event.c
+++ b/arch/s390/kernel/perf_event.c
@@ -260,12 +260,13 @@ static unsigned long __store_trace(struct perf_callchain_entry *entry,
void perf_callchain_kernel(struct perf_callchain_entry *entry,
struct pt_regs *regs)
{
- unsigned long head;
+ unsigned long head, frame_size;
struct stack_frame *head_sf;
if (user_mode(regs))
return;
+ frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
head = regs->gprs[15];
head_sf = (struct stack_frame *) head;
@@ -273,8 +274,9 @@ void perf_callchain_kernel(struct perf_callchain_entry *entry,
return;
head = head_sf->back_chain;
- head = __store_trace(entry, head, S390_lowcore.async_stack - ASYNC_SIZE,
- S390_lowcore.async_stack);
+ head = __store_trace(entry, head,
+ S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
+ S390_lowcore.async_stack + frame_size);
__store_trace(entry, head, S390_lowcore.thread_info,
S390_lowcore.thread_info + THREAD_SIZE);
diff --git a/arch/s390/kernel/stacktrace.c b/arch/s390/kernel/stacktrace.c
index 5acba3cb7220..8f64ebd63767 100644
--- a/arch/s390/kernel/stacktrace.c
+++ b/arch/s390/kernel/stacktrace.c
@@ -59,26 +59,32 @@ static unsigned long save_context_stack(struct stack_trace *trace,
}
}
-void save_stack_trace(struct stack_trace *trace)
+static void __save_stack_trace(struct stack_trace *trace, unsigned long sp)
{
- register unsigned long sp asm ("15");
- unsigned long orig_sp, new_sp;
+ unsigned long new_sp, frame_size;
- orig_sp = sp;
- new_sp = save_context_stack(trace, orig_sp,
- S390_lowcore.panic_stack - PAGE_SIZE,
- S390_lowcore.panic_stack, 1);
- if (new_sp != orig_sp)
- return;
+ frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
+ new_sp = save_context_stack(trace, sp,
+ S390_lowcore.panic_stack + frame_size - PAGE_SIZE,
+ S390_lowcore.panic_stack + frame_size, 1);
new_sp = save_context_stack(trace, new_sp,
- S390_lowcore.async_stack - ASYNC_SIZE,
- S390_lowcore.async_stack, 1);
- if (new_sp != orig_sp)
- return;
+ S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
+ S390_lowcore.async_stack + frame_size, 1);
save_context_stack(trace, new_sp,
S390_lowcore.thread_info,
S390_lowcore.thread_info + THREAD_SIZE, 1);
}
+
+void save_stack_trace(struct stack_trace *trace)
+{
+ register unsigned long r15 asm ("15");
+ unsigned long sp;
+
+ sp = r15;
+ __save_stack_trace(trace, sp);
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = ULONG_MAX;
+}
EXPORT_SYMBOL_GPL(save_stack_trace);
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
@@ -86,6 +92,10 @@ void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
unsigned long sp, low, high;
sp = tsk->thread.ksp;
+ if (tsk == current) {
+ /* Get current stack pointer. */
+ asm volatile("la %0,0(15)" : "=a" (sp));
+ }
low = (unsigned long) task_stack_page(tsk);
high = (unsigned long) task_pt_regs(tsk);
save_context_stack(trace, sp, low, high, 0);
@@ -93,3 +103,14 @@ void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
+
+void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
+{
+ unsigned long sp;
+
+ sp = kernel_stack_pointer(regs);
+ __save_stack_trace(trace, sp);
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = ULONG_MAX;
+}
+EXPORT_SYMBOL_GPL(save_stack_trace_regs);
diff --git a/arch/s390/kernel/trace.c b/arch/s390/kernel/trace.c
index 21a5df99552b..dde7654f5c68 100644
--- a/arch/s390/kernel/trace.c
+++ b/arch/s390/kernel/trace.c
@@ -18,6 +18,9 @@ void trace_s390_diagnose_norecursion(int diag_nr)
unsigned long flags;
unsigned int *depth;
+ /* Avoid lockdep recursion. */
+ if (IS_ENABLED(CONFIG_LOCKDEP))
+ return;
local_irq_save(flags);
depth = this_cpu_ptr(&diagnose_trace_depth);
if (*depth == 0) {
diff --git a/arch/s390/mm/maccess.c b/arch/s390/mm/maccess.c
index fec59c067d0d..792f9c63fbca 100644
--- a/arch/s390/mm/maccess.c
+++ b/arch/s390/mm/maccess.c
@@ -93,15 +93,19 @@ static int __memcpy_real(void *dest, void *src, size_t count)
*/
int memcpy_real(void *dest, void *src, size_t count)
{
+ int irqs_disabled, rc;
unsigned long flags;
- int rc;
if (!count)
return 0;
- local_irq_save(flags);
- __arch_local_irq_stnsm(0xfbUL);
+ flags = __arch_local_irq_stnsm(0xf8UL);
+ irqs_disabled = arch_irqs_disabled_flags(flags);
+ if (!irqs_disabled)
+ trace_hardirqs_off();
rc = __memcpy_real(dest, src, count);
- local_irq_restore(flags);
+ if (!irqs_disabled)
+ trace_hardirqs_on();
+ __arch_local_irq_ssm(flags);
return rc;
}
diff --git a/arch/s390/oprofile/backtrace.c b/arch/s390/oprofile/backtrace.c
index fe0bfe370c45..1884e1759529 100644
--- a/arch/s390/oprofile/backtrace.c
+++ b/arch/s390/oprofile/backtrace.c
@@ -54,12 +54,13 @@ __show_trace(unsigned int *depth, unsigned long sp,
void s390_backtrace(struct pt_regs * const regs, unsigned int depth)
{
- unsigned long head;
+ unsigned long head, frame_size;
struct stack_frame* head_sf;
if (user_mode(regs))
return;
+ frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
head = regs->gprs[15];
head_sf = (struct stack_frame*)head;
@@ -68,8 +69,9 @@ void s390_backtrace(struct pt_regs * const regs, unsigned int depth)
head = head_sf->back_chain;
- head = __show_trace(&depth, head, S390_lowcore.async_stack - ASYNC_SIZE,
- S390_lowcore.async_stack);
+ head = __show_trace(&depth, head,
+ S390_lowcore.async_stack + frame_size - ASYNC_SIZE,
+ S390_lowcore.async_stack + frame_size);
__show_trace(&depth, head, S390_lowcore.thread_info,
S390_lowcore.thread_info + THREAD_SIZE);