pstore: do not use message compression without lock

pstore_compress() uses static stream buffer for zlib-deflate which
easily crashes when several concurrent threads use one shared state.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index c4c9a10c5760..de525ec0b490 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -299,7 +299,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
                 bool compressed;
                 size_t total_len;
 
-                if (big_oops_buf) {
+                if (big_oops_buf && is_locked) {
                         dst = big_oops_buf;
                         hsize = sprintf(dst, "%s#%d Part%u\n", why,
                                                         oopscount, part);