From d73b7aff28bc53c04e1f2e5ccaa5ea43089fb4a4 Mon Sep 17 00:00:00 2001 From: Pete Zaitcev Date: Mon, 10 Nov 2008 21:11:11 -0700 Subject: ub: stub pre_reset and post_reset to fix oops Due to recent changes to usb_reset_device, the following hang occurs: events/0 D 0000000000000000 0 6 2 ffff880037477cc0 0000000000000046 ffff880037477c50 ffffffff80237434 ffffffff80574c80 00000001000a015c 0000000000000286 ffff8800374757d0 ffff88002a31c860 ffff880037475a00 0000000036779140 ffff880037475a00 Call Trace: [] try_to_del_timer_sync+0x52/0x5b [] dma_pool_free+0x1a7/0x1ec [] ub_disconnect+0x8e/0x1ad [ub] [] autoremove_wake_function+0x0/0x2e [] usb_unbind_interface+0x5c/0xb7 [] __device_release_driver+0x95/0xbd [] device_release_driver+0x21/0x2d [] usb_driver_release_interface+0x44/0x83 [] usb_forced_unbind_intf+0x17/0x1d [] usb_reset_device+0x7d/0x114 [] ub_reset_task+0x0/0x293 [ub] [] ub_reset_task+0x1c4/0x293 [ub] [] flush_to_ldisc+0x0/0x1cd [] ub_reset_task+0x0/0x293 [ub] [] run_workqueue+0x87/0x114 [] worker_thread+0xd8/0xe7 [] autoremove_wake_function+0x0/0x2e [] worker_thread+0x0/0xe7 [] kthread+0x47/0x73 [] schedule_tail+0x27/0x60 [] child_rip+0xa/0x11 [] kthread+0x0/0x73 [] child_rip+0x0/0x11 This is because usb_reset_device now unbinds, and that calls disconnect, which in case of ub waits until the reset completes... which deadlocks. Worse, this deadlocks keventd and this takes whole box down. I'm going to fix this properly later, but let's unbreak the driver quickly for non-composite devices at least. Signed-off-by: Pete Zaitcev Cc: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/block/ub.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) (limited to 'drivers/block') diff --git a/drivers/block/ub.c b/drivers/block/ub.c index fccac18d311..048d71d244d 100644 --- a/drivers/block/ub.c +++ b/drivers/block/ub.c @@ -1546,8 +1546,6 @@ static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd) /* * Reset management - * XXX Move usb_reset_device to khubd. Hogging kevent is not a good thing. - * XXX Make usb_sync_reset asynchronous. */ static void ub_reset_enter(struct ub_dev *sc, int try) @@ -1632,6 +1630,22 @@ static void ub_reset_task(struct work_struct *work) spin_unlock_irqrestore(sc->lock, flags); } +/* + * XXX Reset brackets are too much hassle to implement, so just stub them + * in order to prevent forced unbinding (which deadlocks solid when our + * ->disconnect method waits for the reset to complete and this kills keventd). + * + * XXX Tell Alan to move usb_unlock_device inside of usb_reset_device, + * or else the post_reset is invoked, and restats I/O on a locked device. + */ +static int ub_pre_reset(struct usb_interface *iface) { + return 0; +} + +static int ub_post_reset(struct usb_interface *iface) { + return 0; +} + /* * This is called from a process context. */ @@ -2446,6 +2460,8 @@ static struct usb_driver ub_driver = { .probe = ub_probe, .disconnect = ub_disconnect, .id_table = ub_usb_ids, + .pre_reset = ub_pre_reset, + .post_reset = ub_post_reset, }; static int __init ub_init(void) -- cgit v1.2.3 From 31c00fc15ebd35c1647775dbfc167a15d46657fd Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Thu, 13 Nov 2008 21:33:24 +0000 Subject: Create/use more directory structure in the Documentation/ tree. Create Documentation/blockdev/ sub-directory and populate it. Populate the Documentation/serial/ sub-directory. Move MSI-HOWTO.txt to Documentation/PCI/. Move ioctl-number.txt to Documentation/ioctl/. Update all relevant 00-INDEX files. Update all relevant Kconfig files and source files. Signed-off-by: Randy Dunlap --- drivers/block/Kconfig | 29 +++++++++++++++-------------- drivers/block/floppy.c | 2 +- 2 files changed, 16 insertions(+), 15 deletions(-) (limited to 'drivers/block') diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index 61ad8d639ba..0344a8a8321 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -21,7 +21,8 @@ config BLK_DEV_FD ---help--- If you want to use the floppy disk drive(s) of your PC under Linux, say Y. Information about this driver, especially important for IBM - Thinkpad users, is contained in . + Thinkpad users, is contained in + . That file also contains the location of the Floppy driver FAQ as well as location of the fdutils package used to configure additional parameters of the driver at run time. @@ -76,7 +77,7 @@ config PARIDE your computer's parallel port. Most of them are actually IDE devices using a parallel port IDE adapter. This option enables the PARIDE subsystem which contains drivers for many of these external drives. - Read for more information. + Read for more information. If you have said Y to the "Parallel-port support" configuration option, you may share a single port between your printer and other @@ -114,9 +115,9 @@ config BLK_CPQ_DA help This is the driver for Compaq Smart Array controllers. Everyone using these boards should say Y here. See the file - for the current list of boards - supported by this driver, and for further information on the use of - this driver. + for the current list of + boards supported by this driver, and for further information on the + use of this driver. config BLK_CPQ_CISS_DA tristate "Compaq Smart Array 5xxx support" @@ -124,7 +125,7 @@ config BLK_CPQ_CISS_DA help This is the driver for Compaq Smart Array 5xxx controllers. Everyone using these boards should say Y here. - See for the current list of + See for the current list of boards supported by this driver, and for further information on the use of this driver. @@ -135,7 +136,7 @@ config CISS_SCSI_TAPE help When enabled (Y), this option allows SCSI tape drives and SCSI medium changers (tape robots) to be accessed via a Compaq 5xxx array - controller. (See for more details.) + controller. (See for more details.) "SCSI support" and "SCSI tape support" must also be enabled for this option to work. @@ -149,8 +150,8 @@ config BLK_DEV_DAC960 help This driver adds support for the Mylex DAC960, AcceleRAID, and eXtremeRAID PCI RAID controllers. See the file - for further information about - this driver. + for further information + about this driver. To compile this driver as a module, choose M here: the module will be called DAC960. @@ -278,9 +279,9 @@ config BLK_DEV_NBD userland (making server and client physically the same computer, communicating using the loopback network device). - Read for more information, especially - about where to find the server code, which runs in user space and - does not need special kernel support. + Read for more information, + especially about where to find the server code, which runs in user + space and does not need special kernel support. Note that this has nothing to do with the network file systems NFS or Coda; you can say N here even if you intend to use NFS or Coda. @@ -321,8 +322,8 @@ config BLK_DEV_RAM store a copy of a minimal root file system off of a floppy into RAM during the initial install of Linux. - Note that the kernel command line option "ramdisk=XX" is now - obsolete. For details, read . + Note that the kernel command line option "ramdisk=XX" is now obsolete. + For details, read . To compile this driver as a module, choose M here: the module will be called rd. diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 14db747a636..cf29cc4e6ab 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -4124,7 +4124,7 @@ static int __init floppy_setup(char *str) printk("\n"); } else DPRINT("botched floppy option\n"); - DPRINT("Read Documentation/floppy.txt\n"); + DPRINT("Read Documentation/blockdev/floppy.txt\n"); return 0; } -- cgit v1.2.3