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author | Dongdong Deng <dongdong.deng@windriver.com> | 2010-08-30 21:06:00 -0500 |
---|---|---|
committer | Jason Wessel <jason.wessel@windriver.com> | 2010-10-29 13:14:41 -0500 |
commit | 4dacd5c073150cd78dfb6004cbfa71986f0258a4 (patch) | |
tree | 7da8bd47cc31480a44b579d37290339021d11162 /drivers | |
parent | d7ba979d45272385ce0fdf141d922e61ff48e07b (diff) | |
download | linux-4dacd5c073150cd78dfb6004cbfa71986f0258a4.tar.gz linux-4dacd5c073150cd78dfb6004cbfa71986f0258a4.tar.bz2 linux-4dacd5c073150cd78dfb6004cbfa71986f0258a4.zip |
kgdbts: prevent re-entry to kgdbts before it unregisters
The "kgdb_connected" variable of debug_core just indicates whether or
not kgdbts is connected to the debug_core. It does not completely
prevent a script from trying invoke kgdbts again and possibly crashing
the system (see Call Trace below).
The configured variable in kgtbts can be used instead of
kgdb_connected instead of kgdb_connected. The cleanup_kgdbts() can
also be removed because there is no possible way to build kgdbts as a
kernel module that you could unload with rmmod.
Call Trace:
-----------------------------------------------------------------
root:/$ echo kgdbts=V1S1000 > /sys/module/kgdbts/parameters/kgdbts
kgdb: Unregistered I/O driver kgdbts, debugger disabled.
------------[ cut here ]------------
WARNING: at kernel/debug/debug_core.c:1002
kgdb_unregister_io_module+0xec/0x100()
Hardware name: Moon Creek platform
Modules linked in:
Pid: 664, comm: sh Not tainted 2.6.34.1-WR4.0.0.0_standard #58
Call Trace:
[<c103b1ed>] warn_slowpath_common+0x6d/0xa0
[<c1079fdc>] ? kgdb_unregister_io_module+0xec/0x100
[<c1079fdc>] ? kgdb_unregister_io_module+0xec/0x100
[<c10544e0>] ? param_attr_store+0x0/0x20
[<c103b235>] warn_slowpath_null+0x15/0x20
[<c1079fdc>] kgdb_unregister_io_module+0xec/0x100
[<c124e4ea>] cleanup_kgdbts+0x1a/0x20
[<c124eced>] param_set_kgdbts_var+0x6d/0xb0
[<c124ec80>] ? param_set_kgdbts_var+0x0/0xb0
[<c10544f7>] param_attr_store+0x17/0x20
[<c105457c>] module_attr_store+0x2c/0x40
[<c111fe84>] sysfs_write_file+0x94/0xf0
[<c10d42f6>] vfs_write+0x96/0x130
[<c111fdf0>] ? sysfs_write_file+0x0/0xf0
[<c10d44d6>] sys_write+0x46/0xd0
[<c13bf329>] system_call_done+0x0/0x4
---[ end trace 4eb028c6ee43154c ]---
kgdb: Unregistered I/O driver kgdbts, debugger disabled.
-----------------------------------------------------------------
[jason.wessel@windriver.com: remove cleanup_kgdbts() ]
Signed-off-by: Dongdong Deng <dongdong.deng@windriver.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/misc/kgdbts.c | 16 |
1 files changed, 2 insertions, 14 deletions
diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c index 72450237a0f4..59c118c19a91 100644 --- a/drivers/misc/kgdbts.c +++ b/drivers/misc/kgdbts.c @@ -1044,12 +1044,6 @@ static int __init init_kgdbts(void) return configure_kgdbts(); } -static void cleanup_kgdbts(void) -{ - if (configured == 1) - kgdb_unregister_io_module(&kgdbts_io_ops); -} - static int kgdbts_get_char(void) { int val = 0; @@ -1081,10 +1075,8 @@ static int param_set_kgdbts_var(const char *kmessage, struct kernel_param *kp) return 0; } - if (kgdb_connected) { - printk(KERN_ERR - "kgdbts: Cannot reconfigure while KGDB is connected.\n"); - + if (configured == 1) { + printk(KERN_ERR "kgdbts: ERROR: Already configured and running.\n"); return -EBUSY; } @@ -1093,9 +1085,6 @@ static int param_set_kgdbts_var(const char *kmessage, struct kernel_param *kp) if (config[len - 1] == '\n') config[len - 1] = '\0'; - if (configured == 1) - cleanup_kgdbts(); - /* Go and configure with the new params. */ return configure_kgdbts(); } @@ -1123,7 +1112,6 @@ static struct kgdb_io kgdbts_io_ops = { }; module_init(init_kgdbts); -module_exit(cleanup_kgdbts); module_param_call(kgdbts, param_set_kgdbts_var, param_get_string, &kps, 0644); MODULE_PARM_DESC(kgdbts, "<A|V1|V2>[F#|S#][N#]"); MODULE_DESCRIPTION("KGDB Test Suite"); |