The patch titled lockdep: fix ide/proc interaction has been removed from the -mm tree. Its filename was lockdep-fix-ide-proc-interaction.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ Subject: lockdep: fix ide/proc interaction From: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> rmmod/3080 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: (proc_subdir_lock){--..}, at: [<c04a33b0>] remove_proc_entry+0x40/0x191 and this task is already holding: (ide_lock){++..}, at: [<c05651a2>] ide_unregister_subdriver+0x39/0xc8 which would create a new lock dependency: (ide_lock){++..} -> (proc_subdir_lock){--..} but this new dependency connects a hard-irq-safe lock: (ide_lock){++..} ... which became hard-irq-safe at: [<c043c458>] lock_acquire+0x4b/0x6b [<c06129d7>] _spin_lock_irqsave+0x22/0x32 [<c0567870>] ide_intr+0x17/0x1a9 [<c044eb31>] handle_IRQ_event+0x20/0x4d [<c044ebf2>] __do_IRQ+0x94/0xef [<c0406771>] do_IRQ+0x9e/0xbd to a hard-irq-unsafe lock: (proc_subdir_lock){--..} ... which became hard-irq-unsafe at: ... [<c043c458>] lock_acquire+0x4b/0x6b [<c06126ab>] _spin_lock+0x19/0x28 [<c04a32f2>] xlate_proc_name+0x1b/0x99 [<c04a3547>] proc_create+0x46/0xdf [<c04a3642>] create_proc_entry+0x62/0xa5 [<c07c1972>] proc_misc_init+0x1c/0x1d2 [<c07c1844>] proc_root_init+0x4c/0xe9 [<c07ad703>] start_kernel+0x294/0x3b3 [<00000000>] 0x0 Move ide_remove_proc_entries() out from under ide_lock; there is nothing that indicates that this is needed. In specific, the call to ide_add_proc_entries() is unprotected, and there is nothing else in the file using the respective ->proc fields. Also the lock order around destroy_proc_ide_interface() suggests this. Alan sayeth: proc_ide_write_settings walks the setting list under ide_setting_sem, read ditto. remove_proc_entry is doing proc side housekeeping. Looks fine to me, although that old code is such a mess anything could be going on. Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Cc: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxx> --- drivers/ide/ide.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff -puN drivers/ide/ide.c~lockdep-fix-ide-proc-interaction drivers/ide/ide.c --- a/drivers/ide/ide.c~lockdep-fix-ide-proc-interaction +++ a/drivers/ide/ide.c @@ -973,8 +973,8 @@ ide_settings_t *ide_find_setting_by_name * @drive: drive * * Automatically remove all the driver specific settings for this - * drive. This function may sleep and must not be called from IRQ - * context. The caller must hold ide_setting_sem. + * drive. This function may not be called from IRQ context. The + * caller must hold ide_setting_sem. */ static void auto_remove_settings (ide_drive_t *drive) @@ -1874,11 +1874,22 @@ void ide_unregister_subdriver(ide_drive_ { unsigned long flags; - down(&ide_setting_sem); - spin_lock_irqsave(&ide_lock, flags); #ifdef CONFIG_PROC_FS ide_remove_proc_entries(drive->proc, driver->proc); #endif + down(&ide_setting_sem); + spin_lock_irqsave(&ide_lock, flags); + /* + * ide_setting_sem protects the settings list + * ide_lock protects the use of settings + * + * so we need to hold both, ide_settings_sem because we want to + * modify the settings list, and ide_lock because we cannot take + * a setting out that is being used. + * + * OTOH both ide_{read,write}_setting are only ever used under + * ide_setting_sem. + */ auto_remove_settings(drive); spin_unlock_irqrestore(&ide_lock, flags); up(&ide_setting_sem); _ Patches currently in -mm which might be from a.p.zijlstra@xxxxxxxxx are origin.patch tty-signal-tty-locking.patch tty-signal-tty-locking-post-viro-trainwreck.patch tty-signal-tty-locking-post-viro-trainwreck-fix.patch tty-signal-tty-locking-post-viro-trainwreck-fix-fix.patch tty-signal-tty-locking-3270-fix.patch do_task_stat-dont-take-tty_mutex.patch do_acct_process-dont-take-tty_mutex.patch sys_unshare-remove-a-broken-clone_sighand-code.patch remove-the-old-bd_mutex-lockdep-annotation.patch new-bd_mutex-lockdep-annotation.patch remove-lock_key-approach-to-managing-nested-bd_mutex-locks.patch simplify-some-aspects-of-bd_mutex-nesting.patch use-mutex_lock_nested-for-bd_mutex-to-avoid-lockdep-warning.patch avoid-lockdep-warning-in-md.patch bdev-fix-bd_part_count-leak.patch lockdep-annotate-nfsd4-recover-code.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html