path: root/fs/pstore/ram_core.c
diff options
authorAnton Vorontsov <anton.vorontsov@linaro.org>2012-05-26 06:07:49 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-06-13 16:52:39 -0700
commit201e4aca5aa179e6c69a4dcd36a3562e56b8d670 (patch)
tree0d75a50b12cd1c8e39119419ed7c65195b518a16 /fs/pstore/ram_core.c
parent33735a94afdfb39c550b952a40f77c60afdddfa5 (diff)
pstore/ram: Should update old dmesg buffer before reading
Without the update, we'll only see the new dmesg buffer after the reboot, but previously we could see it right away. Making an oops visible in pstore filesystem before reboot is a somewhat dubious feature, but removing it wasn't an intentional change, so let's restore it. For this we have to make persistent_ram_save_old() safe for calling multiple times, and also extern it. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/pstore/ram_core.c')
1 files changed, 8 insertions, 7 deletions
diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c
index 31f8d184f3a..235513c46aa 100644
--- a/fs/pstore/ram_core.c
+++ b/fs/pstore/ram_core.c
@@ -250,23 +250,24 @@ static void notrace persistent_ram_update(struct persistent_ram_zone *prz,
persistent_ram_update_ecc(prz, start, count);
-static void __init
-persistent_ram_save_old(struct persistent_ram_zone *prz)
+void persistent_ram_save_old(struct persistent_ram_zone *prz)
struct persistent_ram_buffer *buffer = prz->buffer;
size_t size = buffer_size(prz);
size_t start = buffer_start(prz);
- char *dest;
- persistent_ram_ecc_old(prz);
+ if (!size)
+ return;
- dest = kmalloc(size, GFP_KERNEL);
- if (dest == NULL) {
+ if (!prz->old_log) {
+ persistent_ram_ecc_old(prz);
+ prz->old_log = kmalloc(size, GFP_KERNEL);
+ }
+ if (!prz->old_log) {
pr_err("persistent_ram: failed to allocate buffer\n");
- prz->old_log = dest;
prz->old_log_size = size;
memcpy(prz->old_log, &buffer->data[start], size - start);
memcpy(prz->old_log + size - start, &buffer->data[0], start);