In lk 2.5.69 (and in 68) both the ide-cd and ide-scsi
modules generate a "sleeping function called from illegal
context" stack trace when removed.
After "rmmod ide-cd" this appears:
Debug: sleeping function called from illegal context
at include/asm/semaphore.h:119
Call Trace:
[<c011dcec>] __might_sleep+0x5c/0x70
[<c025b634>] auto_remove_settings+0x24/0x80
[<c025db8a>] ide_unregister_subdriver+0x15a/0x3d0
[<e10d48df>] ide_cdrom_cleanup+0x2f/0x110 [ide_cd]
[<c02346de>] driver_unregister+0x2e/0x42
[<e10d90e0>] ide_cdrom_driver+0x0/0xd8 [ide_cd]
[<e10d91a8>] ide_cdrom_driver+0xc8/0xd8 [ide_cd]
[<c025e270>] ide_unregister_driver+0x100/0x1df
[<c0155f1f>] unmap_vma_list+0x1f/0x30
[<e10d9200>] +0x0/0x140 [ide_cd]
[<e10d4df2>] +0x12/0x20 [ide_cd]
[<e10d90e0>] ide_cdrom_driver+0x0/0xd8 [ide_cd]
[<c013d336>] sys_delete_module+0x1d6/0x240
[<c0156457>] sys_munmap+0x57/0x80
[<c0109eaf>] syscall_call+0x7/0xb
After "rmmod ide-scsi" this appears:
Debug: sleeping function called from illegal context
at include/asm/semaphore.h:119
Call Trace:
[<e10c8068>] idescsi_driver+0xc8/0xd8 [ide_scsi]
[<c011dcec>] __might_sleep+0x5c/0x70
[<e10c8068>] idescsi_driver+0xc8/0xd8 [ide_scsi]
[<c025b634>] auto_remove_settings+0x24/0x80
[<c025db8a>] ide_unregister_subdriver+0x15a/0x3d0
[<e10c7ff8>] idescsi_driver+0x58/0xd8 [ide_scsi]
[<e10c7ff8>] idescsi_driver+0x58/0xd8 [ide_scsi]
[<e10c542d>] idescsi_cleanup+0x1d/0x60 [ide_scsi]
[<e10c7fa0>] idescsi_driver+0x0/0xd8 [ide_scsi]
[<c025e270>] ide_unregister_driver+0x100/0x1df
[<e10c6e87>] +0xfa/0x10f [ide_scsi]
[<e10c8300>] +0x0/0x140 [ide_scsi]
[<e10c663f>] +0x2f/0x50 [ide_scsi]
[<e10c7fa0>] idescsi_driver+0x0/0xd8 [ide_scsi]
[<c013d336>] sys_delete_module+0x1d6/0x240
[<c0156457>] sys_munmap+0x57/0x80
[<c0109eaf>] syscall_call+0x7/0xb
My .config has these kernel debugging options set:
#
# Kernel hacking
#
CONFIG_DEBUG_KERNEL=y
CONFIG_DEBUG_STACKOVERFLOW=y
CONFIG_DEBUG_SLAB=y
CONFIG_DEBUG_IOVIRT=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_SPINLOCK=y
CONFIG_KALLSYMS=y
CONFIG_DEBUG_SPINLOCK_SLEEP=y
CONFIG_FRAME_POINTER=y
Doug Gilbert
Douglas Gilbert <[email protected]> wrote:
>
> In lk 2.5.69 (and in 68) both the ide-cd and ide-scsi
> modules generate a "sleeping function called from illegal
> context" stack trace when removed.
>
> After "rmmod ide-cd" this appears:
> Debug: sleeping function called from illegal context
> at include/asm/semaphore.h:119
> Call Trace:
> [<c011dcec>] __might_sleep+0x5c/0x70
ide_unregister_subdriver() does spin_lock_irqsave(&ide_lock), then
calls auto_remove_settings(), which does down(&ide_setting_sem);
A simple fix might be:
diff -puN drivers/ide/ide.c~ide_setting_sem-fix drivers/ide/ide.c
--- 25/drivers/ide/ide.c~ide_setting_sem-fix 2003-05-05 01:59:01.000000000 -0700
+++ 25-akpm/drivers/ide/ide.c 2003-05-05 02:00:21.000000000 -0700
@@ -1131,13 +1131,12 @@ ide_settings_t *ide_find_setting_by_name
*
* Automatically remove all the driver specific settings for this
* drive. This function may sleep and must not be called from IRQ
- * context. Takes the settings_lock
+ * context. The caller must hold ide_setting_sem.
*/
static void auto_remove_settings (ide_drive_t *drive)
{
ide_settings_t *setting;
- down(&ide_setting_sem);
repeat:
setting = drive->settings;
while (setting) {
@@ -1147,7 +1146,6 @@ repeat:
}
setting = setting->next;
}
- up(&ide_setting_sem);
}
/**
@@ -2350,9 +2348,11 @@ int ide_unregister_subdriver (ide_drive_
{
unsigned long flags;
+ down(&ide_setting_sem);
spin_lock_irqsave(&ide_lock, flags);
if (drive->usage || drive->driver == &idedefault_driver || DRIVER(drive)->busy) {
spin_unlock_irqrestore(&ide_lock, flags);
+ up(&ide_setting_sem);
return 1;
}
#if defined(CONFIG_BLK_DEV_IDEPNP) && defined(CONFIG_PNP) && defined(MODULE)
@@ -2363,6 +2363,7 @@ int ide_unregister_subdriver (ide_drive_
ide_remove_proc_entries(drive->proc, generic_subdriver_entries);
#endif
auto_remove_settings(drive);
+ up(&ide_setting_sem);
drive->driver = &idedefault_driver;
setup_driver_defaults(drive);
spin_unlock_irqrestore(&ide_lock, flags);
_
Andrew Morton wrote:
> Douglas Gilbert <[email protected]> wrote:
>
>>In lk 2.5.69 (and in 68) both the ide-cd and ide-scsi
>>modules generate a "sleeping function called from illegal
>>context" stack trace when removed.
>>
>>After "rmmod ide-cd" this appears:
>> Debug: sleeping function called from illegal context
>> at include/asm/semaphore.h:119
>> Call Trace:
>> [<c011dcec>] __might_sleep+0x5c/0x70
>
>
> ide_unregister_subdriver() does spin_lock_irqsave(&ide_lock), then
> calls auto_remove_settings(), which does down(&ide_setting_sem);
>
> A simple fix might be:
Andrew,
Thanks. That patch clears the reported problem.
Doug Gilbert
On Llu, 2003-05-05 at 12:51, Douglas Gilbert wrote:
> > ide_unregister_subdriver() does spin_lock_irqsave(&ide_lock), then
> > calls auto_remove_settings(), which does down(&ide_setting_sem);
> >
> > A simple fix might be:
>
> Andrew,
> Thanks. That patch clears the reported problem.
This is already fixed in 2.4.x btw. Just hadn't got pushed into 2.5 yet
The 2.5.x code has another problem as well there is a basically unfixable
deadlock in the proc and config stuff when flipping a device in and out of
scsi mode