[PATCH] ibmasm driver: fix race in command refcount logic

This patch fixes a race in the command reference counting logic by putting
spinlocks around kobject_put() in the command_put function.

- Also added debug messages.

- Changed a memcpy to memcpy_fromio since we are reading from io space.

Signed-off-by: Max Asbock <masbock@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/misc/ibmasm/dot_command.c b/drivers/misc/ibmasm/dot_command.c
index 478a8d898fc1..13c52f866e2e 100644
--- a/drivers/misc/ibmasm/dot_command.c
+++ b/drivers/misc/ibmasm/dot_command.c
@@ -33,7 +33,13 @@ void ibmasm_receive_message(struct service_processor *sp, void *message, int mes
         u32 size;
         struct dot_command_header *header = (struct dot_command_header *)message;
 
+        if (message_size == 0)
+                return;
+
         size = get_dot_command_size(message);
+        if (size == 0)
+                return;
+
         if (size > message_size)
                 size = message_size;
 
@@ -67,7 +73,7 @@ int ibmasm_send_driver_vpd(struct service_processor *sp)
         u8 *vpd_data;
         int result = 0;
 
-        command = ibmasm_new_command(INIT_BUFFER_SIZE);
+        command = ibmasm_new_command(sp, INIT_BUFFER_SIZE);
         if (command == NULL)
                 return -ENOMEM;
 
@@ -121,7 +127,7 @@ int ibmasm_send_os_state(struct service_processor *sp, int os_state)
         struct os_state_command *os_state_cmd;
         int result = 0;
 
-        cmd = ibmasm_new_command(sizeof(struct os_state_command));
+        cmd = ibmasm_new_command(sp, sizeof(struct os_state_command));
         if (cmd == NULL)
                 return -ENOMEM;