sparc64: Ensure perf can access user stacks

[linux-2.6-block.git] / arch / sparc / kernel / perf_event.c

diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c
index 3091267c5cc3d30dba854f152ff8d9bbc06c65a2..b1144d6acffe8d3d96ba1d9b73865d66d9e16a69 100644 (file)
--- a/arch/sparc/kernel/perf_event.c
+++ b/arch/sparc/kernel/perf_event.c
@@ -1828,11 +1828,16 @@ static void perf_callchain_user_32(struct perf_callchain_entry *entry,
 void
 perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
 {
+       mm_segment_t old_fs;
+
        perf_callchain_store(entry, regs->tpc);
 
        if (!current->mm)
                return;
 
+       old_fs = get_fs();
+       set_fs(USER_DS);
+
        flushw_user();
 
        pagefault_disable();
@@ -1843,4 +1848,6 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
                perf_callchain_user_64(entry, regs);
 
        pagefault_enable();
+
+       set_fs(old_fs);
 }