sugar/linux
1
0
Fork 0
Code Activity

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

Browse Source 
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>
This commit is contained in:
Max Asbock
2005-06-21 17:16:36 -07:00
committed by Linus Torvalds
parent 278d72ae88
commit 8818760512
6 changed files with 51 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/misc/ibmasm/heartbeat.c
View File

@@ -25,6 +25,7 @@
#include <linux/notifier.h>
#include "ibmasm.h"
#include "dot_command.h"
#include "lowlevel.h"
static int suspend_heartbeats = 0;
@@ -62,7 +63,7 @@ void ibmasm_unregister_panic_notifier(void)
int ibmasm_heartbeat_init(struct service_processor *sp)
{
sp->heartbeat = ibmasm_new_command(HEARTBEAT_BUFFER_SIZE);
sp->heartbeat = ibmasm_new_command(sp, HEARTBEAT_BUFFER_SIZE);
if (sp->heartbeat == NULL)
return -ENOMEM;
@@ -71,6 +72,12 @@ int ibmasm_heartbeat_init(struct service_processor *sp)
void ibmasm_heartbeat_exit(struct service_processor *sp)
{
char tsbuf[32];
dbg("%s:%d at %s\n", __FUNCTION__, __LINE__, get_timestamp(tsbuf));
ibmasm_wait_for_response(sp->heartbeat, IBMASM_CMD_TIMEOUT_NORMAL);
dbg("%s:%d at %s\n", __FUNCTION__, __LINE__, get_timestamp(tsbuf));
suspend_heartbeats = 1;
command_put(sp->heartbeat);
}
@@ -78,14 +85,16 @@ void ibmasm_receive_heartbeat(struct service_processor *sp, void *message, size
{
struct command *cmd = sp->heartbeat;
struct dot_command_header *header = (struct dot_command_header *)cmd->buffer;
char tsbuf[32];
dbg("%s:%d at %s\n", __FUNCTION__, __LINE__, get_timestamp(tsbuf));
if (suspend_heartbeats)
return;
/* return the received dot command to sender */
cmd->status = IBMASM_CMD_PENDING;
size = min(size, cmd->buffer_size);
memcpy(cmd->buffer, message, size);
memcpy_fromio(cmd->buffer, message, size);
header->type = sp_write;
ibmasm_exec_command(sp, cmd);
}