Use dd to test a SCSI device:
1. echo "blocked" >/sys/block/sda/device/state
2. dd if=/dev/sda of=/mnt/t.log bs=1M count=10
3. echo "running" >/sys/block/sda/device/state
dd should finish this work after step 3, but it hangs.
After step2, the call chain is this:
blk_mq_dispatch_rq_list-->scsi_queue_rq-->prep_to_mq
prep_to_mq will return BLK_STS_RESOURCE, and scsi_queue_rq will
transition it to BLK_STS_DEV_RESOURCE which means that driver can
guarantee that IO dispatch will be triggered in future when the
resource is available. Need to follow the rule if we set the device
state to running.
[mkp: tweaked commit description and code comment as suggested by Bart]
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This removes the legacy (non-mq) IO path for SCSI.
Cc: linux-scsi@vger.kernel.org
Acked-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A long time ago the unfortunate decision was taken to add a self-deletion
attribute to the sysfs SCSI device directory. That decision was unfortunate
because self-deletion is really tricky. We can't drop that attribute
because widely used user space software depends on it, namely the
rescan-scsi-bus.sh script. Hence this patch that avoids that writing into
that attribute triggers a deadlock. See also commit 7973cbd9fbd9 ("[PATCH]
add sysfs attributes to scan and delete scsi_devices").
This patch avoids that self-removal triggers the following deadlock:
======================================================
WARNING: possible circular locking dependency detected
4.18.0-rc2-dbg+ #5 Not tainted
------------------------------------------------------
modprobe/6539 is trying to acquire lock:
000000008323c4cd (kn->count#202){++++}, at: kernfs_remove_by_name_ns+0x45/0x90
but task is already holding lock:
00000000a6ec2c69 (&shost->scan_mutex){+.+.}, at: scsi_remove_host+0x21/0x150 [scsi_mod]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&shost->scan_mutex){+.+.}:
__mutex_lock+0xfe/0xc70
mutex_lock_nested+0x1b/0x20
scsi_remove_device+0x26/0x40 [scsi_mod]
sdev_store_delete+0x27/0x30 [scsi_mod]
dev_attr_store+0x3e/0x50
sysfs_kf_write+0x87/0xa0
kernfs_fop_write+0x190/0x230
__vfs_write+0xd2/0x3b0
vfs_write+0x101/0x270
ksys_write+0xab/0x120
__x64_sys_write+0x43/0x50
do_syscall_64+0x77/0x230
entry_SYSCALL_64_after_hwframe+0x49/0xbe
-> #0 (kn->count#202){++++}:
lock_acquire+0xd2/0x260
__kernfs_remove+0x424/0x4a0
kernfs_remove_by_name_ns+0x45/0x90
remove_files.isra.1+0x3a/0x90
sysfs_remove_group+0x5c/0xc0
sysfs_remove_groups+0x39/0x60
device_remove_attrs+0x82/0xb0
device_del+0x251/0x580
__scsi_remove_device+0x19f/0x1d0 [scsi_mod]
scsi_forget_host+0x37/0xb0 [scsi_mod]
scsi_remove_host+0x9b/0x150 [scsi_mod]
sdebug_driver_remove+0x4b/0x150 [scsi_debug]
device_release_driver_internal+0x241/0x360
device_release_driver+0x12/0x20
bus_remove_device+0x1bc/0x290
device_del+0x259/0x580
device_unregister+0x1a/0x70
sdebug_remove_adapter+0x8b/0xf0 [scsi_debug]
scsi_debug_exit+0x76/0xe8 [scsi_debug]
__x64_sys_delete_module+0x1c1/0x280
do_syscall_64+0x77/0x230
entry_SYSCALL_64_after_hwframe+0x49/0xbe
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&shost->scan_mutex);
lock(kn->count#202);
lock(&shost->scan_mutex);
lock(kn->count#202);
*** DEADLOCK ***
2 locks held by modprobe/6539:
#0: 00000000efaf9298 (&dev->mutex){....}, at: device_release_driver_internal+0x68/0x360
#1: 00000000a6ec2c69 (&shost->scan_mutex){+.+.}, at: scsi_remove_host+0x21/0x150 [scsi_mod]
stack backtrace:
CPU: 10 PID: 6539 Comm: modprobe Not tainted 4.18.0-rc2-dbg+ #5
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Call Trace:
dump_stack+0xa4/0xf5
print_circular_bug.isra.34+0x213/0x221
__lock_acquire+0x1a7e/0x1b50
lock_acquire+0xd2/0x260
__kernfs_remove+0x424/0x4a0
kernfs_remove_by_name_ns+0x45/0x90
remove_files.isra.1+0x3a/0x90
sysfs_remove_group+0x5c/0xc0
sysfs_remove_groups+0x39/0x60
device_remove_attrs+0x82/0xb0
device_del+0x251/0x580
__scsi_remove_device+0x19f/0x1d0 [scsi_mod]
scsi_forget_host+0x37/0xb0 [scsi_mod]
scsi_remove_host+0x9b/0x150 [scsi_mod]
sdebug_driver_remove+0x4b/0x150 [scsi_debug]
device_release_driver_internal+0x241/0x360
device_release_driver+0x12/0x20
bus_remove_device+0x1bc/0x290
device_del+0x259/0x580
device_unregister+0x1a/0x70
sdebug_remove_adapter+0x8b/0xf0 [scsi_debug]
scsi_debug_exit+0x76/0xe8 [scsi_debug]
__x64_sys_delete_module+0x1c1/0x280
do_syscall_64+0x77/0x230
entry_SYSCALL_64_after_hwframe+0x49/0xbe
See also https://www.mail-archive.com/linux-scsi@vger.kernel.org/msg54525.html.
Fixes: ac0ece9174 ("scsi: use device_remove_file_self() instead of device_schedule_callback()")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
No functional change.
Just introduce scsi_host_busy() and replace the direct read of
scsi_host->host_busy with this new API.
Cc: Omar Sandoval <osandov@fb.com>,
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>,
Cc: James Bottomley <james.bottomley@hansenpartnership.com>,
Cc: Christoph Hellwig <hch@lst.de>,
Cc: Don Brace <don.brace@microsemi.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Space for SCSI blist flags is gradually running out. Change the type to
__u64 and fix a checkpatch complaint about symbolic mode flags in
scsi_devinfo.c.
Make checkpatch happy by replacing simple_strtoul() with kstrtoull().
Signed-off-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use the just introduced const_ilog2() macro to avoid sparse errors.
Signed-off-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This is mostly updates of the usual drivers: arcmsr, qla2xx, lpfc,
ufs, mpt3sas, hisi_sas. In addition we have removed several really
old drivers: sym53c416, NCR53c406a, fdomain, fdomain_cs and removed
the old scsi_module.c initialization from all remaining drivers. Plus
an assortment of bug fixes, initialization errors and other minor
fixes.
Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This is mostly updates of the usual drivers: arcmsr, qla2xx, lpfc,
ufs, mpt3sas, hisi_sas.
In addition we have removed several really old drivers: sym53c416,
NCR53c406a, fdomain, fdomain_cs and removed the old scsi_module.c
initialization from all remaining drivers.
Plus an assortment of bug fixes, initialization errors and other minor
fixes"
* tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (168 commits)
scsi: ufs: Add support for Auto-Hibernate Idle Timer
scsi: ufs: sysfs: reworking of the rpm_lvl and spm_lvl entries
scsi: qla2xxx: fx00 copypaste typo
scsi: qla2xxx: fix error message on <qla2400
scsi: smartpqi: update driver version
scsi: smartpqi: workaround fw bug for oq deletion
scsi: arcmsr: Change driver version to v1.40.00.05-20180309
scsi: arcmsr: Sleep to avoid CPU stuck too long for waiting adapter ready
scsi: arcmsr: Handle adapter removed due to thunderbolt cable disconnection.
scsi: arcmsr: Rename ACB_F_BUS_HANG_ON to ACB_F_ADAPTER_REMOVED for adapter hot-plug
scsi: qla2xxx: Update driver version to 10.00.00.06-k
scsi: qla2xxx: Fix Async GPN_FT for FCP and FC-NVMe scan
scsi: qla2xxx: Cleanup code to improve FC-NVMe error handling
scsi: qla2xxx: Fix FC-NVMe IO abort during driver reset
scsi: qla2xxx: Fix retry for PRLI RJT with reason of BUSY
scsi: qla2xxx: Remove nvme_done_list
scsi: qla2xxx: Return busy if rport going away
scsi: qla2xxx: Fix n2n_ae flag to prevent dev_loss on PDB change
scsi: qla2xxx: Add FC-NVMe abort processing
scsi: qla2xxx: Add changes for devloss timeout in driver
...
The current BSG design tries to shoe-horn the transport-specific
passthrough commands into the overall framework for SCSI passthrough
requests. This has a couple problems:
- each passthrough queue has to set the QUEUE_FLAG_SCSI_PASSTHROUGH flag
despite not dealing with SCSI commands at all. Because of that these
queues could also incorrectly accept SCSI commands from in-kernel
users or through the legacy SCSI_IOCTL_SEND_COMMAND ioctl.
- the real SCSI bsg queues also incorrectly accept bsg requests of the
BSG_SUB_PROTOCOL_SCSI_TRANSPORT type
- the bsg transport code is almost unredable because it tries to reuse
different SCSI concepts for its own purpose.
This patch instead adds a new bsg_ops structure to handle the two cases
differently, and thus solves all of the above problems. Another side
effect is that the bsg-lib queues also don't need to embedd a
struct scsi_request anymore.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The patch introduces an additional field in the scsi_host_template
structure - struct attribute_group **sdev_group. This field allows to
define groups of attributes. It will provide an ability to use binary
attributes as well as device attributes and to group them under
subfolders if necessary.
Signed-off-by: Stanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This is mostly updates of the usual driver suspects: arcmsr,
scsi_debug, mpt3sas, lpfc, cxlflash, qla2xxx, aacraid, megaraid_sas,
hisi_sas. We also have a rework of the libsas hotplug handling to
make it more robust, a slew of 32 bit time conversions and fixes, and
a host of the usual minor updates and style changes. The biggest
potential for regressions is the libsas hotplug changes, but so far
they seem stable under testing.
Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This is mostly updates of the usual driver suspects: arcmsr,
scsi_debug, mpt3sas, lpfc, cxlflash, qla2xxx, aacraid, megaraid_sas,
hisi_sas.
We also have a rework of the libsas hotplug handling to make it more
robust, a slew of 32 bit time conversions and fixes, and a host of the
usual minor updates and style changes. The biggest potential for
regressions is the libsas hotplug changes, but so far they seem stable
under testing"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (313 commits)
scsi: qla2xxx: Fix logo flag for qlt_free_session_done()
scsi: arcmsr: avoid do_gettimeofday
scsi: core: Add VENDOR_SPECIFIC sense code definitions
scsi: qedi: Drop cqe response during connection recovery
scsi: fas216: fix sense buffer initialization
scsi: ibmvfc: Remove unneeded semicolons
scsi: hisi_sas: fix a bug in hisi_sas_dev_gone()
scsi: hisi_sas: directly attached disk LED feature for v2 hw
scsi: hisi_sas: devicetree: bindings: add LED feature for v2 hw
scsi: megaraid_sas: NVMe passthrough command support
scsi: megaraid: use ktime_get_real for firmware time
scsi: fnic: use 64-bit timestamps
scsi: qedf: Fix error return code in __qedf_probe()
scsi: devinfo: fix format of the device list
scsi: qla2xxx: Update driver version to 10.00.00.05-k
scsi: qla2xxx: Add XCB counters to debugfs
scsi: qla2xxx: Fix queue ID for async abort with Multiqueue
scsi: qla2xxx: Fix warning for code intentation in __qla24xx_handle_gpdb_event()
scsi: qla2xxx: Fix warning during port_name debug print
scsi: qla2xxx: Fix warning in qla2x00_async_iocb_timeout()
...
As it turned out device_get() doesn't use kref_get_unless_zero(), so we
will be always getting a device pointer. Consequently, we need to check
for the device state in __scsi_remove_target() to avoid tripping over
deleted objects.
Fixes: fbce4d97fd ("scsi: fixup kernel warning during rmmod()")
Reported-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use the type blist_flags_t for all variables that represent blacklist
flags. Additionally, suppress recently introduced sparse warnings
related to blacklist flags.
[mkp: fixed commit id]
Fixes: 5ebde4694e ("scsi: Use 'blist_flags_t' for scsi_devinfo flags")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Remove this function since it has an empty body.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas,
megaraid_sas, pm80xx, mpt3sas, be2iscsi, hpsa. and a host of minor
updates.
There's no major behaviour change or additions to the core in all of
this, so the potential for regressions should be small (biggest
potential being in the scsi error handler changes).
Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas,
megaraid_sas, pm80xx, mpt3sas, be2iscsi, hpsa. and a host of minor
updates.
There's no major behaviour change or additions to the core in all of
this, so the potential for regressions should be small (biggest
potential being in the scsi error handler changes)"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (203 commits)
scsi: lpfc: Fix hard lock up NMI in els timeout handling.
scsi: mpt3sas: remove a stray KERN_INFO
scsi: mpt3sas: cleanup _scsih_pcie_enumeration_event()
scsi: aacraid: use timespec64 instead of timeval
scsi: scsi_transport_fc: add 64GBIT and 128GBIT port speed definitions
scsi: qla2xxx: Suppress a kernel complaint in qla_init_base_qpair()
scsi: mpt3sas: fix dma_addr_t casts
scsi: be2iscsi: Use kasprintf
scsi: storvsc: Avoid excessive host scan on controller change
scsi: lpfc: fix kzalloc-simple.cocci warnings
scsi: mpt3sas: Update mpt3sas driver version.
scsi: mpt3sas: Fix sparse warnings
scsi: mpt3sas: Fix nvme drives checking for tlr.
scsi: mpt3sas: NVMe drive support for BTDHMAPPING ioctl command and log info
scsi: mpt3sas: Add-Task-management-debug-info-for-NVMe-drives.
scsi: mpt3sas: scan and add nvme device after controller reset
scsi: mpt3sas: Set NVMe device queue depth as 128
scsi: mpt3sas: Handle NVMe PCIe device related events generated from firmware.
scsi: mpt3sas: API's to remove nvme drive from sml
scsi: mpt3sas: API 's to support NVMe drive addition to SML
...
Each scsi device is scanned according to the found blacklist flags, but
this information is never presented to sysfs. This makes it quite hard
to figure out if blacklisting worked as expected. With this patch we're
exporting an additional attribute 'blacklist' containing the blacklist
flags for this device.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Calling rmmod() on a FC driver will results in warnings like
WARNING: CPU: 60 PID: 14640 at fs/sysfs/group.c:237 device_del+0x54/0x240()
sysfs group ffffffff81eff140 not found for kobject '3:0:0:3'
The problem here is that during scsi_remove_target() we will iterate
over all devices, but fail to remove any of those as the call to
scsi_device_get() fails the check to module_is_live(). Hence the
devices will not be removed at this point, but all intermediate
structures like fc rport etc. will be. Later on during
scsi_forget_host() the devices are removed for real, but the device
parent is already removed and causes this warning.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Kyle Fortin <kyle.fortin@oracle.com>
Tested-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Device handlers are optional, and for some handlers like ALUA only
implemented for certain device types. So suppress any errors for
unsupported devices.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Introduce struct scsi_vpd for the VPD page length, data and the RCU head
that will be used to free the VPD data. Use kfree_rcu() instead of
kfree() to free VPD data. Move the VPD buffer pointer check inside the
RCU read lock in the sysfs code. Only annotate pointers that are shared
across threads with __rcu. Use rcu_dereference() when dereferencing an
RCU pointer. This patch suppresses about twenty sparse complaints about
the vpd_pg8[03] pointers. This patch also fixes a race condition, namely
that updating of the VPD pointers and length variables in struct
scsi_device was not atomic with reference to the code reading these
variables. See also "Does the update code tolerate concurrent accesses?"
in Documentation/RCU/checklist.txt.
Fixes: commit 09e2b0b146 ("scsi: rescan VPD attributes")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Shane Seymour <shane.seymour@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This patch avoids that smatch reports the following warning:
drivers/scsi/scsi_sysfs.c:117: check_set() error: strncmp() '"-"' too small (2 vs 20)
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If scsi_host_template->host_reset is NULL and the user requests an
adapter reset through
echo adapter > /sys/class/scsi_host/hostx/host_reset
-EINVAL will be returned even though the "adapter" argument is perfectly
valid.
Change this so that we only return -EINVAL if the provided string is
invalid. If the host does not implement a ->host_reset function we'll
return -EOPNOTSUPP.
[mkp: tweaked patch description]
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The addition of the STARGET_REMOVE state had the side effect of
introducing a race condition that can cause a crash.
scsi_target_reap_ref_release() checks the starget->state to
see if it still in STARGET_CREATED, and if so, skips calling
transport_remove_device() and device_del(), because the starget->state
is only set to STARGET_RUNNING after scsi_target_add() has called
device_add() and transport_add_device().
However, if an rport loss occurs while a target is being scanned,
it can happen that scsi_remove_target() will be called while the
starget is still in the STARGET_CREATED state. In this case, the
starget->state will be set to STARGET_REMOVE, and as a result,
scsi_target_reap_ref_release() will take the wrong path. The end
result is a panic:
[ 1255.356653] Oops: 0000 [#1] SMP
[ 1255.360154] Modules linked in: x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel ghash_clmulni_i
[ 1255.393234] CPU: 5 PID: 149 Comm: kworker/u96:4 Tainted: G W 4.11.0+ #8
[ 1255.401879] Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013
[ 1255.410327] Workqueue: scsi_wq_6 fc_scsi_scan_rport [scsi_transport_fc]
[ 1255.417720] task: ffff88060ca8c8c0 task.stack: ffffc900048a8000
[ 1255.424331] RIP: 0010:kernfs_find_ns+0x13/0xc0
[ 1255.429287] RSP: 0018:ffffc900048abbf0 EFLAGS: 00010246
[ 1255.435123] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 1255.443083] RDX: 0000000000000000 RSI: ffffffff8188d659 RDI: 0000000000000000
[ 1255.451043] RBP: ffffc900048abc10 R08: 0000000000000000 R09: 0000012433fe0025
[ 1255.459005] R10: 0000000025e5a4b5 R11: 0000000025e5a4b5 R12: ffffffff8188d659
[ 1255.466972] R13: 0000000000000000 R14: ffff8805f55e5088 R15: 0000000000000000
[ 1255.474931] FS: 0000000000000000(0000) GS:ffff880616b40000(0000) knlGS:0000000000000000
[ 1255.483959] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1255.490370] CR2: 0000000000000068 CR3: 0000000001c09000 CR4: 00000000000406e0
[ 1255.498332] Call Trace:
[ 1255.501058] kernfs_find_and_get_ns+0x31/0x60
[ 1255.505916] sysfs_unmerge_group+0x1d/0x60
[ 1255.510498] dpm_sysfs_remove+0x22/0x60
[ 1255.514783] device_del+0xf4/0x2e0
[ 1255.518577] ? device_remove_file+0x19/0x20
[ 1255.523241] attribute_container_class_device_del+0x1a/0x20
[ 1255.529457] transport_remove_classdev+0x4e/0x60
[ 1255.534607] ? transport_add_class_device+0x40/0x40
[ 1255.540046] attribute_container_device_trigger+0xb0/0xc0
[ 1255.546069] transport_remove_device+0x15/0x20
[ 1255.551025] scsi_target_reap_ref_release+0x25/0x40
[ 1255.556467] scsi_target_reap+0x2e/0x40
[ 1255.560744] __scsi_scan_target+0xaa/0x5b0
[ 1255.565312] scsi_scan_target+0xec/0x100
[ 1255.569689] fc_scsi_scan_rport+0xb1/0xc0 [scsi_transport_fc]
[ 1255.576099] process_one_work+0x14b/0x390
[ 1255.580569] worker_thread+0x4b/0x390
[ 1255.584651] kthread+0x109/0x140
[ 1255.588251] ? rescuer_thread+0x330/0x330
[ 1255.592730] ? kthread_park+0x60/0x60
[ 1255.596815] ret_from_fork+0x29/0x40
[ 1255.600801] Code: 24 08 48 83 42 40 01 5b 41 5c 5d c3 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90
[ 1255.621876] RIP: kernfs_find_ns+0x13/0xc0 RSP: ffffc900048abbf0
[ 1255.628479] CR2: 0000000000000068
[ 1255.632756] ---[ end trace 34a69ba0477d036f ]---
Fix this by adding another scsi_target state STARGET_CREATED_REMOVE
to distinguish this case.
Fixes: f05795d3d7 ("scsi: Add intermediate STARGET_REMOVE state to scsi_target_state")
Reported-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If a device is blocked, make __scsi_remove_device() cause it to
transition to the DEL state. This means that all the commands issued in
.shutdown() will error in the mid-layer, thus making the removal proceed
without being stopped.
This patch is a slightly modified version of a patch from James
Bottomley. This patch avoids that the following lockup occurs:
Call Trace:
schedule+0x35/0x80
schedule_timeout+0x237/0x2d0
io_schedule_timeout+0xa6/0x110
wait_for_completion_io+0xa3/0x110
blk_execute_rq+0xdf/0x120
scsi_execute+0xce/0x150 [scsi_mod]
scsi_execute_req_flags+0x8f/0xf0 [scsi_mod]
sd_sync_cache+0xa9/0x190 [sd_mod]
sd_shutdown+0x6a/0x100 [sd_mod]
sd_remove+0x64/0xc0 [sd_mod]
__device_release_driver+0x8d/0x120
device_release_driver+0x1e/0x30
bus_remove_device+0xf9/0x170
device_del+0x127/0x240
__scsi_remove_device+0xc1/0xd0 [scsi_mod]
scsi_forget_host+0x57/0x60 [scsi_mod]
scsi_remove_host+0x72/0x110 [scsi_mod]
srp_remove_work+0x8b/0x200 [ib_srp]
Reported-by: Israel Rukshin <israelr@mellanox.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Israel Rukshin <israelr@mellanox.com>
Cc: Max Gurtovoy <maxg@mellanox.com>
Cc: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Serializing SCSI device state changes avoids that two state changes can
occur concurrently, e.g. the state changes in scsi_target_block() and
__scsi_remove_device(). This serialization is essential to make patch
"Make __scsi_remove_device go straight from BLOCKED to DEL" work
reliably.
Enable this mechanism for all scsi_target_*block() callers but not for
the scsi_internal_device_unblock() calls from the mpt3sas driver because
that driver can call scsi_internal_device_unblock() from atomic context.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
A race between scanning and fc_remote_port_delete() may result in a
permanent stop if the device gets blocked before scsi_sysfs_add_sdev()
and unblocked after. The reason is that blocking a device sets both the
SDEV_BLOCKED state and the QUEUE_FLAG_STOPPED. However,
scsi_sysfs_add_sdev() unconditionally sets SDEV_RUNNING which causes the
device to be ignored by scsi_target_unblock() and thus never have its
QUEUE_FLAG_STOPPED cleared leading to a device which is apparently
running but has a stopped queue.
We actually have two places where SDEV_RUNNING is set: once in
scsi_add_lun() which respects the blocked flag and once in
scsi_sysfs_add_sdev() which doesn't. Since the second set is entirely
spurious, simply remove it to fix the problem.
Cc: <stable@vger.kernel.org>
Reported-by: Zengxi Chen <chenzengxi@huawei.com>
Signed-off-by: Wei Fang <fangwei1@huawei.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Now that we've done a more comprehensive fix with the intermediate
target state we can remove the previous hack introduced with commit
90a88d6ef8 ("scsi: fix soft lockup in scsi_remove_target() on module
removal").
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add intermediate STARGET_REMOVE state to scsi_target_state to avoid
running into the BUG_ON() in scsi_target_reap(). The STARGET_REMOVE
state is only valid in the path from scsi_remove_target() to
scsi_target_destroy() indicating this target is going to be removed.
This re-fixes the problem introduced in commits bc3f02a795 ("[SCSI]
scsi_remove_target: fix softlockup regression on hot remove") and
4099819356 ("scsi: restart list search after unlock in
scsi_remove_target") in a more comprehensive way.
[mkp: Included James' fix for scsi_target_destroy()]
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Fixes: 4099819356
Cc: stable@vger.kernel.org
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: James Bottomley <jejb@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
On larger installations it is useful to disable automatic LUN scanning,
and only add the required LUNs via udev rules. This can speed up bootup
dramatically.
This patch introduces a new scan module parameter value 'manual', which
works like 'none', but can be overridden by setting the 'rescan' value
from scsi_scan_target to 'SCSI_SCAN_MANUAL'. And it updates all
relevant callers to set the 'rescan' value to 'SCSI_SCAN_MANUAL' if
invoked via the 'scan' option in sysfs.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Avoid that building with W=1 causes gcc to report warnings about symbols
that have not been declared.
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The test for the existence vpd_pg83 is inverted.
Fixes: 7e47976bcf ("scsi_sysfs: add 'is_bin_visible' callback")
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reported-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Laurence Oberman loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
'device_add' will be evaluating the 'is_visible' callback when creating
the sysfs attributes. As by this time the device handler has not been
attached the 'access_state' attribute will never be visible.
This patch moves the code around so that the device handler is present
by the time 'is_visible' is evaluated to correctly display the
'access_state' attribute.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add an 'access_state' field to struct scsi_device and display them in
sysfs as 'access_state' and 'preferred_path' attribute.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add 'is_bin_visible' callback to blank out unsupported vpd pages.
Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use scsi_vpd_lun_id() to export the world-wide unique id (wwid) to
sysfs. Note that this is the 'best' wwid according to the rules in
scsi_vpd_lun_id(), not every possible wwid presented by the drive.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
device handler initialisation might fail due to a number of
reasons. But as device_handlers are optional this shouldn't
cause us to disable the device entirely.
So just ignore errors from scsi_dh_add_device().
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As scsi_dh.c is now always compiled in we should be moving
the 'dh_state' attribute to the generic code.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The SCSI sd driver probes SCSI devices asynchronously. The sd_remove()
function, called indirectly by device_del(), waits until asynchronous
probing has finished. Since the block layer queue must only be cleaned
up after probing has finished, device_del() has to be called before
blk_cleanup_queue(). Hence revert commit bf2cf3baa2.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
The VPD page information might change, so we need to be able to update
it. This patch implements a VPD page rescan whenever the 'rescan' sysfs
attribute is triggered.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
On some host errors storvsc module tries to remove sdev by scheduling a job
which does the following:
sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
if (sdev) {
scsi_remove_device(sdev);
scsi_device_put(sdev);
}
While this code seems correct the following crash is observed:
general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
RIP: 0010:[<ffffffff81169979>] [<ffffffff81169979>] bdi_destroy+0x39/0x220
...
[<ffffffff814aecdc>] ? _raw_spin_unlock_irq+0x2c/0x40
[<ffffffff8127b7db>] blk_cleanup_queue+0x17b/0x270
[<ffffffffa00b54c4>] __scsi_remove_device+0x54/0xd0 [scsi_mod]
[<ffffffffa00b556b>] scsi_remove_device+0x2b/0x40 [scsi_mod]
[<ffffffffa00ec47d>] storvsc_remove_lun+0x3d/0x60 [hv_storvsc]
[<ffffffff81080791>] process_one_work+0x1b1/0x530
...
The problem comes with the fact that many such jobs (for the same device)
are being scheduled simultaneously. While scsi_remove_device() uses
shost->scan_mutex and scsi_device_lookup() will fail for a device in
SDEV_DEL state there is no protection against someone who did
scsi_device_lookup() before we actually entered __scsi_remove_device(). So
the whole scenario looks like that: two callers do simultaneous (or
preemption happens) calls to scsi_device_lookup() ant these calls succeed
for both of them, after that they try doing scsi_remove_device().
shost->scan_mutex only serializes their calls to __scsi_remove_device()
and we end up doing the cleanup path twice.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Sorry for the delay in this patch which was mostly caused by getting the
merger of the mpt2/mpt3sas driver, which was seen as an essential item of
maintenance work to do before the drivers diverge too much. Unfortunately,
this caused a compile failure (detected by linux-next), which then had to be
fixed up and incubated. In addition to the mpt2/3sas rework, there are
updates from pm80xx, lpfc, bnx2fc, hpsa, ipr, aacraid, megaraid_sas, storvsc
and ufs plus an assortment of changes including some year 2038 issues, a fix
for a remove before detach issue in some drivers and a couple of other minor
issues.
Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull final round of SCSI updates from James Bottomley:
"Sorry for the delay in this patch which was mostly caused by getting
the merger of the mpt2/mpt3sas driver, which was seen as an essential
item of maintenance work to do before the drivers diverge too much.
Unfortunately, this caused a compile failure (detected by linux-next),
which then had to be fixed up and incubated.
In addition to the mpt2/3sas rework, there are updates from pm80xx,
lpfc, bnx2fc, hpsa, ipr, aacraid, megaraid_sas, storvsc and ufs plus
an assortment of changes including some year 2038 issues, a fix for a
remove before detach issue in some drivers and a couple of other minor
issues"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (141 commits)
mpt3sas: fix inline markers on non inline function declarations
sd: Clear PS bit before Mode Select.
ibmvscsi: set max_lun to 32
ibmvscsi: display default value for max_id, max_lun and max_channel.
mptfusion: don't allow negative bytes in kbuf_alloc_2_sgl()
scsi: pmcraid: replace struct timeval with ktime_get_real_seconds()
mvumi: 64bit value for seconds_since1970
be2iscsi: Fix bogus WARN_ON length check
scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice
mpt3sas: Bump mpt3sas driver version to 09.102.00.00
mpt3sas: Single driver module which supports both SAS 2.0 & SAS 3.0 HBAs
mpt2sas, mpt3sas: Update the driver versions
mpt3sas: setpci reset kernel oops fix
mpt3sas: Added OEM Gen2 PnP ID branding names
mpt3sas: Refcount fw_events and fix unsafe list usage
mpt3sas: Refcount sas_device objects and fix unsafe list usage
mpt3sas: sysfs attribute to report Backup Rail Monitor Status
mpt3sas: Ported WarpDrive product SSS6200 support
mpt3sas: fix for driver fails EEH, recovery from injected pci bus error
mpt3sas: Manage MSI-X vectors according to HBA device type
...
Writing a number to /sys/bus/scsi/devices/<sdev>/queue_ramp_up_period
returns the value of that number instead of the number of bytes written.
This behavior can confuse programs expecting POSIX write() semantics.
Fix this by returning the number of bytes written instead.
Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Writing a number to /sys/bus/scsi/devices/<sdev>/queue_ramp_up_period
returns the value of that number instead of the number of bytes written.
This behavior can confuse programs expecting POSIX write() semantics.
Fix this by returning the number of bytes written instead.
Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Export the RAW SCSI Inquiry to sysfs as binfile. This way the data can be used
by userland without the need to have and ioctl or use the sg_inq tool.
Here is an example of the provided data
linux:~ # hexdump /sys/class/scsi_device/1\:0\:0\:0/device/inquiry
0000000 8005 3205 001f 0000 4551 554d 2020 2020
0000010 4551 554d 4420 4456 522d 4d4f 2020 2020
0000020 2e32 2e33
0000024
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When dropping a lock while iterating a list we must restart the search
as other threads could have manipulated the list under us. Without this
we can get stuck in an endless loop. This bug was introduced by
commit bc3f02a795
Author: Dan Williams <djbw@fb.com>
Date: Tue Aug 28 22:12:10 2012 -0700
[SCSI] scsi_remove_target: fix softlockup regression on hot remove
Which was itself trying to fix a reported soft lockup issue
http://thread.gmane.org/gmane.linux.kernel/1348679
However, we believe even with this revert of the original patch, the soft
lockup problem has been fixed by
commit f2495e228f
Author: James Bottomley <JBottomley@Parallels.com>
Date: Tue Jan 21 07:01:41 2014 -0800
[SCSI] dual scan thread bug fix
Thanks go to Dan Williams <dan.j.williams@intel.com> for tracking all this
prior history down.
Reported-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Fixes: bc3f02a795
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Odin.com>
The commit 1bab0de027 ("dm-mpath, scsi_dh: don't let dm detach device
handlers") removed reference counting of attached scsi device handler.
As a result, handler data is freed immediately via scsi_dh->detach()
in the context of scsi_remove_device() where activation request can be
still in flight.
This patch moves scsi_dh_handler_detach() to sdev releasing function,
scsi_device_dev_release_usercontext(), at that point the device
is already in quiesced state.
Fixes: 1bab0de027 ("dm-mpath, scsi_dh: don't let dm detach device handlers")
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Stop building scsi_dh as a separate module and integrate it fully into the
core SCSI code with explicit callouts at bus scan time. For now the
callouts are placed at the same point as the old bus notifiers were called,
but in the future we will be able to look at ALUA INQUIRY data earlier on.
Note that this also means that the device handler modules need to be loaded
by the time we scan the bus. The next patches will add support for
autoloading device handlers at bus scan time to make sure they are always
loaded if they are enabled in the kernel config.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
