summaryrefslogtreecommitdiffstats
path: root/arch/s390
diff options
context:
space:
mode:
authorPhilipp Rudo <prudo@linux.ibm.com>2020-04-06 14:47:48 +0200
committerVasily Gorbik <gor@linux.ibm.com>2020-04-22 16:20:55 +0200
commit8ebf6da9db1b2a20bb86cc1bee2552e894d03308 (patch)
tree5f29c829690f812c8690f40ebedcf53fb60aae27 /arch/s390
parentae83d0b416db002fe95601e7f97f64b59514d936 (diff)
downloadlinux-8ebf6da9db1b2a20bb86cc1bee2552e894d03308.tar.bz2
s390/ftrace: fix potential crashes when switching tracers
Switching tracers include instruction patching. To prevent that a instruction is patched while it's read the instruction patching is done in stop_machine 'context'. This also means that any function called during stop_machine must not be traced. Thus add 'notrace' to all functions called within stop_machine. Fixes: 1ec2772e0c3c ("s390/diag: add a statistic for diagnose calls") Fixes: 38f2c691a4b3 ("s390: improve wait logic of stop_machine") Fixes: 4ecf0a43e729 ("processor: get rid of cpu_relax_yield") Signed-off-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch/s390')
-rw-r--r--arch/s390/kernel/diag.c2
-rw-r--r--arch/s390/kernel/smp.c4
-rw-r--r--arch/s390/kernel/trace.c2
3 files changed, 4 insertions, 4 deletions
diff --git a/arch/s390/kernel/diag.c b/arch/s390/kernel/diag.c
index 61f2b0412345..ccba63aaeb47 100644
--- a/arch/s390/kernel/diag.c
+++ b/arch/s390/kernel/diag.c
@@ -133,7 +133,7 @@ void diag_stat_inc(enum diag_stat_enum nr)
}
EXPORT_SYMBOL(diag_stat_inc);
-void diag_stat_inc_norecursion(enum diag_stat_enum nr)
+void notrace diag_stat_inc_norecursion(enum diag_stat_enum nr)
{
this_cpu_inc(diag_stat.counter[nr]);
trace_s390_diagnose_norecursion(diag_map[nr].code);
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 7eaabbab2213..10dbb12eb14d 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -403,7 +403,7 @@ int smp_find_processor_id(u16 address)
return -1;
}
-bool arch_vcpu_is_preempted(int cpu)
+bool notrace arch_vcpu_is_preempted(int cpu)
{
if (test_cpu_flag_of(CIF_ENABLED_WAIT, cpu))
return false;
@@ -413,7 +413,7 @@ bool arch_vcpu_is_preempted(int cpu)
}
EXPORT_SYMBOL(arch_vcpu_is_preempted);
-void smp_yield_cpu(int cpu)
+void notrace smp_yield_cpu(int cpu)
{
if (!MACHINE_HAS_DIAG9C)
return;
diff --git a/arch/s390/kernel/trace.c b/arch/s390/kernel/trace.c
index 490b52e85014..11a669f3cc93 100644
--- a/arch/s390/kernel/trace.c
+++ b/arch/s390/kernel/trace.c
@@ -14,7 +14,7 @@ EXPORT_TRACEPOINT_SYMBOL(s390_diagnose);
static DEFINE_PER_CPU(unsigned int, diagnose_trace_depth);
-void trace_s390_diagnose_norecursion(int diag_nr)
+void notrace trace_s390_diagnose_norecursion(int diag_nr)
{
unsigned long flags;
unsigned int *depth;