NetBSD Problem Report #51129

From www@NetBSD.org  Tue May 10 06:32:12 2016
Return-Path: <www@NetBSD.org>
Received: from mail.netbsd.org (mail.netbsd.org [199.233.217.200])
	(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
	(Client CN "mail.netbsd.org", Issuer "Postmaster NetBSD.org" (verified OK))
	by mollari.NetBSD.org (Postfix) with ESMTPS id 72D6F7AA95
	for <gnats-bugs@gnats.NetBSD.org>; Tue, 10 May 2016 06:32:12 +0000 (UTC)
Message-Id: <20160510063211.7EB367AAAF@mollari.NetBSD.org>
Date: Tue, 10 May 2016 06:32:11 +0000 (UTC)
From: coypu@sdf.org
Reply-To: coypu@sdf.org
To: gnats-bugs@NetBSD.org
Subject: Disconnecting USB SD card without umount causes file operations to hang
X-Send-Pr-Version: www-1.0

>Number:         51129
>Category:       kern
>Synopsis:       Disconnecting USB SD card without umount causes file operations to hang
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    skrll
>State:          closed
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue May 10 06:35:00 +0000 2016
>Closed-Date:    Sat Feb 20 09:18:44 +0000 2021
>Last-Modified:  Sat Feb 20 09:18:44 +0000 2021
>Originator:     coypu
>Release:        NetBSD 7.99.29
>Organization:
>Environment:
NetBSD net.Home 7.99.29 NetBSD 7.99.29 (GENERIC) #1: Tue May 10 07:40:15 IDT 2016  fly@net.Home:/usr/obj/sys/arch/amd64/compile/GENERIC amd64
>Description:
attach SD card reader with rpi.img on it
mount /dev/sd0a /new
detach SD card reader

any operation will hang. ls, umount (even umount -f), etc.
>How-To-Repeat:

>Fix:

>Release-Note:

>Audit-Trail:
From: coypu@SDF.ORG
To: gnats-bugs@netbsd.org
Cc: 
Subject: Re: kern/51129: Disconnecting USB SD card without umount causes file
 operations to hang
Date: Tue, 10 May 2016 06:37:29 +0000

 Clarifying, not *any* file operation.

 Examples of file operations that hang:
 mount -v
 umount -f /new
 ls /new
 etc.

 Examples of file operations that do not hang:
 ls /

From: coypu@SDF.ORG
To: gnats-bugs@netbsd.org
Cc: 
Subject: Re: kern/51129: Disconnecting USB SD card without umount causes file
 operations to hang
Date: Tue, 10 May 2016 06:43:52 +0000

 From dmesg after trying to plug it back in a few times:

 umass0 at uhub0 port 1 configuration 1 interface 0
 umass0: USB FLASH DISK USB FLASH DISK, rev 2.00/2.01, addr 5
 umass0: using SCSI over Bulk-Only
 scsibus0 at umass0: 2 targets, 1 lun per target
 sd0 at scsibus0 target 0 lun 0: <USB Mass, Storage Device,
 \001\000\000\001> disk removable
 sd0: fabricating a geometry
 sd0: 15193 MB, 15193 cyl, 64 head, 32 sec, 512 bytes/sect x 31116288
 sectors
 sd0: fabricating a geometry
 /dev/sd0a: file system not clean (fs_clean=0x10); please fsck(8)
 /dev/sd0a: lost blocks 0 files 0
 umass0: BBB reset failed, TIMEOUT
 umass0: BBB bulk-in clear stall failed, TIMEOUT
 umass0: BBB bulk-out clear stall failed, TIMEOUT
 umass0: BBB reset failed, TIMEOUT
 umass0: BBB bulk-in clear stall failed, TIMEOUT
 umass0: BBB bulk-out clear stall failed, TIMEOUT
 umass0: BBB reset failed, TIMEOUT
 umass0: BBB bulk-in clear stall failed, TIMEOUT
 umass0: BBB bulk-out clear stall failed, TIMEOUT
 ...


From: coypu@SDF.ORG
To: gnats-bugs@netbsd.org
Cc: 
Subject: Re: kern/51129: Disconnecting USB SD card without umount causes file
 operations to hang
Date: Tue, 10 May 2016 07:17:51 +0000

 Bonus:

 if you umount /new, you can now execute the following:
 mv /new /new/a/b

 whereas normally it would say device busy.

 if you run umount -f instead, this operation will also hang.

 normal umount is stuck in biowait
 umount -f is stuck in vcache
 mv after umount -f is stuck in vcache

 Maybe bonus:

 I could lock my system, not sure which scenario is needed because
 I can't always make it happen (placing a lock on /, can't execute
 new programs).

From: David Holland <dholland-bugs@netbsd.org>
To: gnats-bugs@NetBSD.org
Cc: 
Subject: Re: kern/51129: Disconnecting USB SD card without umount causes file
 operations to hang
Date: Sat, 14 May 2016 18:05:40 +0000

 On Tue, May 10, 2016 at 07:20:00AM +0000, coypu@SDF.ORG wrote:
  >  Bonus:
  >  
  >  if you umount /new, you can now execute the following:
  >  mv /new /new/a/b
  >  
  >  whereas normally it would say device busy.
  >  
  >  if you run umount -f instead, this operation will also hang.
  >  
  >  normal umount is stuck in biowait
  >  umount -f is stuck in vcache
  >  mv after umount -f is stuck in vcache

 So, just to make sure I understand:

    mkdir /new         [so it's empty]
    attach device
    mount /dev/sd0a /new
    pull device
    umount /new &      [hangs in background]
    mv /new /new/a/b   [succeeds and *doesn't* hang?]

 and a/b is a subdirectory on the device? That is ... odd.

 and also
    mkdir /new         [so it's empty]
    attach device
    mount /dev/sd0a /new
    pull device
    umount -f /new     [hangs]

 ? (which is still a bug, but less surprising)

 -- 
 David A. Holland
 dholland@netbsd.org

State-Changed-From-To: open->closed
State-Changed-By: maya@NetBSD.org
State-Changed-When: Sun, 26 Feb 2017 02:42:21 +0000
State-Changed-Why:
same as 51127 which is mine too.


State-Changed-From-To: closed->open
State-Changed-By: jdolecek@NetBSD.org
State-Changed-When: Thu, 20 Apr 2017 17:18:20 +0000
State-Changed-Why:
Somebody should fix this. Better keep it open.


From: coypu@sdf.org
To: gnats-bugs@NetBSD.org
Cc: jdolecek@NetBSD.org
Subject: Re: kern/51129 (Disconnecting USB SD card without umount causes file
 operations to hang)
Date: Thu, 20 Apr 2017 17:34:49 +0000

 Plug USB
 mount
 disconnect, reconnect USB
 umount

 660      1 3  10         0   fffffe8475baaaa0             umount biowait
 crash> bt/a fffffe8475baaaa0
 trace: pid 660 lid 1 at 0xfffffe811d942880
 sleepq_block() at sleepq_block+0x97
 cv_wait() at cv_wait+0x9e
 biowait() at biowait+0x42
 bread() at bread+0x2e
 ffs_init_vnode() at ffs_init_vnode+0xa7
 ffs_loadvnode() at ffs_loadvnode+0x43
 vcache_get() at vcache_get+0x293
 ufs_vget() at ufs_vget+0x23
 ufs_root() at ufs_root+0x1c
 VFS_ROOT() at VFS_ROOT+0x1c
 lookup_once() at lookup_once+0x250
 namei_tryemulroot.constprop.9() at namei_tryemulroot.constprop.9+0x3a9
 namei() at namei+0x43
 fd_nameiat.isra.2() at fd_nameiat.isra.2+0x54
 do_sys_statat() at do_sys_statat+0x77
 sys___lstat50() at sys___lstat50+0x25
 syscall() at syscall+0x1bc
 --- syscall (number 441) ---
 785bb70ae67a:


 Idea that may not be sensible: using cv_timedwait instead in biowait and
 setting an error on EWOULDBLOCK.

 Alternatively using this time to cv_broadcast failures (???)
 umass0: BBB reset failed, TIMEOUT
 umass0: BBB bulk-in clear stall failed, TIMEOUT
 umass0: BBB bulk-out clear stall failed, TIMEOUT

Responsible-Changed-From-To: kern-bug-people->skrll
Responsible-Changed-By: skrll@NetBSD.org
Responsible-Changed-When: Fri, 21 Apr 2017 15:43:13 +0000
Responsible-Changed-Why:
Take


From: Nick Hudson <skrll@netbsd.org>
To: gnats-bugs@NetBSD.org, kern-bug-people@netbsd.org,
 gnats-admin@netbsd.org, netbsd-bugs@netbsd.org
Cc: 
Subject: Re: kern/51129: Disconnecting USB SD card without umount causes file
 operations to hang
Date: Sat, 22 Apr 2017 06:37:50 +0100

 This is a multi-part message in MIME format.
 --------------050605020508030409040902
 Content-Type: text/plain; charset=windows-1252; format=flowed
 Content-Transfer-Encoding: 7bit

 Does this patch fix things for you?

 Thanks,
 Nick

 --------------050605020508030409040902
 Content-Type: text/x-patch;
  name="pr51129.diff"
 Content-Transfer-Encoding: 7bit
 Content-Disposition: attachment;
  filename="pr51129.diff"

 Index: sys/dev/usb/umass.c
 ===================================================================
 RCS file: /cvsroot/src/sys/dev/usb/umass.c,v
 retrieving revision 1.157
 diff -u -p -w -b -r1.157 umass.c
 --- sys/dev/usb/umass.c	21 Nov 2016 08:27:30 -0000	1.157
 +++ sys/dev/usb/umass.c	22 Apr 2017 05:34:54 -0000
 @@ -796,6 +796,10 @@ umass_detach(device_t self, int flags)

  	DPRINTFM(UDMASS_USB, "sc %p detached", sc, 0, 0, 0);

 +	mutex_enter(&sc->sc_lock);
 +	sc->sc_dying = true;
 +	mutex_exit(&sc->sc_lock);
 +
  	pmf_device_deregister(self);

  	/* Abort the pipes to wake up any waiting processes. */
 @@ -1156,9 +1160,6 @@ umass_bbb_state(struct usbd_xfer *xfer, 
  		   "sc->sc_wire == 0x%02x wrong for umass_bbb_state\n",
  		   sc->sc_wire);

 -	if (sc->sc_dying)
 -		return;
 -
  	/*
  	 * State handling for BBB transfers.
  	 *
 @@ -1173,6 +1174,18 @@ umass_bbb_state(struct usbd_xfer *xfer, 
  	DPRINTFM(UDMASS_BBB, "sc %p xfer %p, transfer_state %d dir %d", sc,
  	    xfer, sc->transfer_state, sc->transfer_dir);

 +	if (err == USBD_CANCELLED) {
 +		DPRINTFM(UDMASS_BBB, "sc %p xfer %p cancelled", sc,
 +		    xfer, 0, 0);
 +
 +		sc->transfer_state = TSTATE_IDLE;
 +		sc->transfer_cb(sc, sc->transfer_priv, 0, STATUS_TIMEOUT);
 +		return;
 +	}
 +
 +	if (sc->sc_dying)
 +		return;
 +
  	switch (sc->transfer_state) {

  	/***** Bulk Transfer *****/
 @@ -1609,6 +1622,13 @@ umass_cbi_state(struct usbd_xfer *xfer, 
  		   "sc->sc_wire == 0x%02x wrong for umass_cbi_state\n",
  		   sc->sc_wire);

 +	if (err == USBD_CANCELLED) {
 +		DPRINTFM(UDMASS_BBB, "sc %p xfer %p cancelled", sc, xfer, 0, 0);
 +		sc->transfer_state = TSTATE_IDLE;
 +		sc->transfer_cb(sc, sc->transfer_priv, 0, STATUS_TIMEOUT);
 +		return;
 +	}
 +
  	if (sc->sc_dying)
  		return;

 Index: sys/dev/usb/umass_scsipi.c
 ===================================================================
 RCS file: /cvsroot/src/sys/dev/usb/umass_scsipi.c,v
 retrieving revision 1.54
 diff -u -p -w -b -r1.54 umass_scsipi.c
 --- sys/dev/usb/umass_scsipi.c	21 Nov 2016 08:27:30 -0000	1.54
 +++ sys/dev/usb/umass_scsipi.c	22 Apr 2017 05:34:54 -0000
 @@ -444,6 +444,10 @@ umass_scsipi_cb(struct umass_softc *sc, 
  		xs->error = XS_RESET;
  		break;

 +	case STATUS_TIMEOUT:
 +		xs->error = XS_TIMEOUT;
 +		break;
 +
  	default:
  		panic("%s: Unknown status %d in umass_scsipi_cb",
  			device_xname(sc->sc_dev), status);
 Index: sys/dev/usb/umassvar.h
 ===================================================================
 RCS file: /cvsroot/src/sys/dev/usb/umassvar.h,v
 retrieving revision 1.38
 diff -u -p -w -b -r1.38 umassvar.h
 --- sys/dev/usb/umassvar.h	3 Jul 2016 07:27:37 -0000	1.38
 +++ sys/dev/usb/umassvar.h	22 Apr 2017 05:34:54 -0000
 @@ -135,6 +135,7 @@ typedef void (*umass_callback)(struct um
  #define STATUS_CMD_UNKNOWN	1	/* will have to fetch sense */
  #define STATUS_CMD_FAILED	2	/* transfer was ok, command failed */
  #define STATUS_WIRE_FAILED	3	/* couldn't even get command across */
 +#define STATUS_TIMEOUT		4	/* transfer aborted */

  typedef void (*umass_wire_xfer)(struct umass_softc *, int, void *, int, void *,
  				int, int, u_int, int, umass_callback, void *);


 --------------050605020508030409040902--

From: coypu@sdf.org
To: gnats-bugs@NetBSD.org
Cc: skrll@NetBSD.org
Subject: Re: kern/51129: Disconnecting USB SD card without umount causes file
 operations to hang
Date: Sat, 22 Apr 2017 08:43:09 +0000

 On Sat, Apr 22, 2017 at 05:40:01AM +0000, Nick Hudson wrote:
 >  Does this patch fix things for you?
 >  
 >  Thanks,
 >  Nick


 It works, thanks!
 Now 'cd /mnt' and 'umount /mnt' fail with EIO

From: "Nick Hudson" <skrll@netbsd.org>
To: gnats-bugs@gnats.NetBSD.org
Cc: 
Subject: PR/51129 CVS commit: src/sys/dev/usb
Date: Tue, 25 Apr 2017 05:36:03 +0000

 Module Name:	src
 Committed By:	skrll
 Date:		Tue Apr 25 05:36:03 UTC 2017

 Modified Files:
 	src/sys/dev/usb: umass.c

 Log Message:
 In umass_detach set sc_dyring so that further attempts at transfers will
 fail.  This fixes part of

 PR/51129 (Disconnecting USB SD card without umount causes file operations to hang)


 To generate a diff of this commit:
 cvs rdiff -u -r1.157 -r1.158 src/sys/dev/usb/umass.c

 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.

State-Changed-From-To: open->feedback
State-Changed-By: skrll@NetBSD.org
State-Changed-When: Sun, 16 Feb 2020 20:47:44 +0000
State-Changed-Why:
Is it fixed now?


State-Changed-From-To: feedback->closed
State-Changed-By: skrll@NetBSD.org
State-Changed-When: Sat, 20 Feb 2021 09:18:44 +0000
State-Changed-Why:
assume fixed. please raise a new PR if you stil have problems.


>Unformatted:

Home	PR Database Search