diff options
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index ca8c8bdc1143..8822ae65a506 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -26,6 +26,7 @@ #include <linux/linkage.h> #include <linux/uaccess.h> #include <linux/kprobes.h> +#include <linux/vmalloc.h> #include <linux/ftrace.h> #include <linux/module.h> #include <linux/percpu.h> @@ -6626,6 +6627,19 @@ static int allocate_trace_buffers(struct trace_array *tr, int size) */ allocate_snapshot = false; #endif + + /* + * Because of some magic with the way alloc_percpu() works on + * x86_64, we need to synchronize the pgd of all the tables, + * otherwise the trace events that happen in x86_64 page fault + * handlers can't cope with accessing the chance that a + * alloc_percpu()'d memory might be touched in the page fault trace + * event. Oh, and we need to audit all other alloc_percpu() and vmalloc() + * calls in tracing, because something might get triggered within a + * page fault trace event! + */ + vmalloc_sync_mappings(); + return 0; } |