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Linux kernel
============
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several of them using the Restructured Text markup notation.
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irqs allocated with devm_request_irq() should not be freed using
free_irq(). Doing so causes a dangling pointer and a subsequent double
free.
Link: https://lore.kernel.org/r/20210519130519.2661938-1-yangyingliang@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Some commands (such as INQUIRY) may return less data than the initiator
requested. To avoid conducting useless information, set the right residual
count to make upper layer aware of this.
Before (INQUIRY PAGE 0xB0 with 128B buffer):
$ sg_raw -r 128 /dev/sda 12 01 B0 00 80 00
SCSI Status: Good
Received 128 bytes of data:
00 00 b0 00 3c 01 00 00 00 00 00 00 00 00 00 00 00 ...<............
10 00 00 00 00 00 01 00 00 00 00 00 40 00 00 08 00 ...........@....
20 80 00 00 00 00 00 00 00 00 00 20 00 00 00 00 00 .......... .....
30 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
50 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
60 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
After:
$ sg_raw -r 128 /dev/sda 12 01 B0 00 80 00
SCSI Status: Good
Received 64 bytes of data:
00 00 b0 00 3c 01 00 00 00 00 00 00 00 00 00 00 00 ...<............
10 00 00 00 00 00 01 00 00 00 00 00 40 00 00 08 00 ...........@....
20 80 00 00 00 00 00 00 00 00 00 20 00 00 00 00 00 .......... .....
30 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
[mkp: clarified description]
Link: https://lore.kernel.org/r/03C41093-B62E-43A2-913E-CFC92F1C70C3@vmware.com
Signed-off-by: Matt Wang <wwentao@vmware.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Return failure from bnx2fc_eh_abort() if io_req is already in ABTS
processing.
Link: https://lore.kernel.org/r/20210519061416.19321-1-jhasan@marvell.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Javed Hasan <jhasan@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Building aicasm with gcc 10.2 + gas 26.1 causes these errors:
multiple definition of `args';
multiple definition of `yylineno';
args came from the expansion of:
STAILQ_HEAD(macro_arg_list, macro_arg) args;
The definition of the macro_arg_list structure is needed, the global
variable 'args' is not, so delete it.
yylineno is defined by flex, so defining it in bison/*.y file is not
needed. Also delete this.
Link: https://lore.kernel.org/r/20210517205057.1850010-1-trix@redhat.com
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
With CONFIG_AIC7XXX_BUILD_FIRMWARE, there is this representative error:
aicasm: Stopped at file ./drivers/scsi/aic7xxx/aic7xxx.seq,
line 271 - Undefined symbol MSG_SIMPLE_Q_TAG referenced
MSG_SIMPLE_Q_TAG used to be defined in drivers/scsi/aic7xxx/scsi_message.h
as:
#define MSG_SIMPLE_Q_TAG 0x20 /* O/O */
The new definition in include/scsi/scsi.h is:
#define SIMPLE_QUEUE_TAG 0x20
But aicasm can not handle the all the preprocessor directives in scsi.h, so
add MSG_SIMPLE_Q_TAB and other required defines back to scsi_message.h.
Link: https://lore.kernel.org/r/20210517132451.1832233-1-trix@redhat.com
Fixes: d8cd784ff7b3 ("scsi: aic7xxx: aic79xx: Drop internal SCSI message definition"
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This has us use raw_smp_processor_id() in iblock's plug_device callout.
smp_processor_id() is not needed here, because we are running from a per
CPU work item that is also queued to run on a worker thread that is
normally bound to a specific CPU. If the worker thread did end up switching
CPUs then it's handled the same way we handle when the work got moved to a
different CPU's worker thread, where we will just end up sending I/O from
the new CPU.
Link: https://lore.kernel.org/r/20210519222640.5153-1-michael.christie@oracle.com
Fixes: 415ccd9811da ("scsi: target: iblock: Add backend plug/unplug callouts")
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If sas_notify_lldd_dev_found() fails then this code calls:
sas_unregister_dev(port, dev);
which removes "dev", our list iterator, from the list. This could lead to
an endless loop. We need to use list_for_each_entry_safe().
Link: https://lore.kernel.org/r/YKUeq6gwfGcvvhty@mwanda
Fixes: 303694eeee5e ("[SCSI] libsas: suspend / resume support")
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Commit f5ce815f34bc ("scsi: target: tcmu: Support DATA_BLOCK_SIZE = N *
PAGE_SIZE") introduced xas_next() calls to iterate xarray elements. These
calls triggered the WARNING "suspicious RCU usage" at tcmu device set up
[1]. In the call stack of xas_next(), xas_load() was called. According to
its comment, this function requires "the xa_lock or the RCU lock".
To avoid the warning:
- Guard the small loop calling xas_next() in tcmu_get_empty_block with RCU
lock.
- In the large loop in tcmu_copy_data using RCU lock would possibly
disable preemtion for a long time (copy multi MBs). Therefore replace
XA_STATE, xas_set and xas_next with a single xa_load.
[1]
[ 1899.867091] =============================
[ 1899.871199] WARNING: suspicious RCU usage
[ 1899.875310] 5.13.0-rc1+ #41 Not tainted
[ 1899.879222] -----------------------------
[ 1899.883299] include/linux/xarray.h:1182 suspicious rcu_dereference_check() usage!
[ 1899.890940] other info that might help us debug this:
[ 1899.899082] rcu_scheduler_active = 2, debug_locks = 1
[ 1899.905719] 3 locks held by kworker/0:1/1368:
[ 1899.910161] #0: ffffa1f8c8b98738 ((wq_completion)target_submission){+.+.}-{0:0}, at: process_one_work+0x1ee/0x580
[ 1899.920732] #1: ffffbd7040cd7e78 ((work_completion)(&q->sq.work)){+.+.}-{0:0}, at: process_one_work+0x1ee/0x580
[ 1899.931146] #2: ffffa1f8d1c99768 (&udev->cmdr_lock){+.+.}-{3:3}, at: tcmu_queue_cmd+0xea/0x160 [target_core_user]
[ 1899.941678] stack backtrace:
[ 1899.946093] CPU: 0 PID: 1368 Comm: kworker/0:1 Not tainted 5.13.0-rc1+ #41
[ 1899.953070] Hardware name: System manufacturer System Product Name/PRIME Z270-A, BIOS 1302 03/15/2018
[ 1899.962459] Workqueue: target_submission target_queued_submit_work [target_core_mod]
[ 1899.970337] Call Trace:
[ 1899.972839] dump_stack+0x6d/0x89
[ 1899.976222] xas_descend+0x10e/0x120
[ 1899.979875] xas_load+0x39/0x50
[ 1899.983077] tcmu_get_empty_blocks+0x115/0x1c0 [target_core_user]
[ 1899.989318] queue_cmd_ring+0x1da/0x630 [target_core_user]
[ 1899.994897] ? rcu_read_lock_sched_held+0x3f/0x70
[ 1899.999695] ? trace_kmalloc+0xa6/0xd0
[ 1900.003501] ? __kmalloc+0x205/0x380
[ 1900.007167] tcmu_queue_cmd+0x12f/0x160 [target_core_user]
[ 1900.012746] __target_execute_cmd+0x23/0xa0 [target_core_mod]
[ 1900.018589] transport_generic_new_cmd+0x1f3/0x370 [target_core_mod]
[ 1900.025046] transport_handle_cdb_direct+0x34/0x50 [target_core_mod]
[ 1900.031517] target_queued_submit_work+0x43/0xe0 [target_core_mod]
[ 1900.037837] process_one_work+0x268/0x580
[ 1900.041952] ? process_one_work+0x580/0x580
[ 1900.046195] worker_thread+0x55/0x3b0
[ 1900.049921] ? process_one_work+0x580/0x580
[ 1900.054192] kthread+0x143/0x160
[ 1900.057499] ? kthread_create_worker_on_cpu+0x40/0x40
[ 1900.062661] ret_from_fork+0x1f/0x30
Link: https://lore.kernel.org/r/20210519135440.26773-1-bostroesser@gmail.com
Fixes: f5ce815f34bc ("scsi: target: tcmu: Support DATA_BLOCK_SIZE = N * PAGE_SIZE")
Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Bodo Stroesser <bostroesser@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The BUG message "BUG: using smp_processor_id() in preemptible [00000000]
code" was observed for TCMU devices with kernel config DEBUG_PREEMPT.
The message was observed when blktests block/005 was run on TCMU devices
with fileio backend or user:zbc backend [1]. The commit 1130b499b4a7
("scsi: target: tcm_loop: Use LIO wq cmd submission helper") triggered the
symptom. The commit modified work queue to handle commands and changed
'current->nr_cpu_allowed' at smp_processor_id() call.
The message was also observed at system shutdown when TCMU devices were not
cleaned up [2]. The function smp_processor_id() was called in SCSI host
work queue for abort handling, and triggered the BUG message. This symptom
was observed regardless of the commit 1130b499b4a7 ("scsi: target:
tcm_loop: Use LIO wq cmd submission helper").
To avoid the preemptible code check at smp_processor_id(), get CPU ID with
raw_smp_processor_id() instead. The CPU ID is used for performance
improvement then thread move to other CPU will not affect the code.
[1]
[ 56.468103] run blktests block/005 at 2021-05-12 14:16:38
[ 57.369473] check_preemption_disabled: 85 callbacks suppressed
[ 57.369480] BUG: using smp_processor_id() in preemptible [00000000] code: fio/1511
[ 57.369506] BUG: using smp_processor_id() in preemptible [00000000] code: fio/1510
[ 57.369512] BUG: using smp_processor_id() in preemptible [00000000] code: fio/1506
[ 57.369552] caller is __target_init_cmd+0x157/0x170 [target_core_mod]
[ 57.369606] CPU: 4 PID: 1506 Comm: fio Not tainted 5.13.0-rc1+ #34
[ 57.369613] Hardware name: System manufacturer System Product Name/PRIME Z270-A, BIOS 1302 03/15/2018
[ 57.369617] Call Trace:
[ 57.369621] BUG: using smp_processor_id() in preemptible [00000000] code: fio/1507
[ 57.369628] dump_stack+0x6d/0x89
[ 57.369642] check_preemption_disabled+0xc8/0xd0
[ 57.369628] caller is __target_init_cmd+0x157/0x170 [target_core_mod]
[ 57.369655] __target_init_cmd+0x157/0x170 [target_core_mod]
[ 57.369695] target_init_cmd+0x76/0x90 [target_core_mod]
[ 57.369732] tcm_loop_queuecommand+0x109/0x210 [tcm_loop]
[ 57.369744] scsi_queue_rq+0x38e/0xc40
[ 57.369761] __blk_mq_try_issue_directly+0x109/0x1c0
[ 57.369779] blk_mq_try_issue_directly+0x43/0x90
[ 57.369790] blk_mq_submit_bio+0x4e5/0x5d0
[ 57.369812] submit_bio_noacct+0x46e/0x4e0
[ 57.369830] __blkdev_direct_IO_simple+0x1a3/0x2d0
[ 57.369859] ? set_init_blocksize.isra.0+0x60/0x60
[ 57.369880] generic_file_read_iter+0x89/0x160
[ 57.369898] blkdev_read_iter+0x44/0x60
[ 57.369906] new_sync_read+0x102/0x170
[ 57.369929] vfs_read+0xd4/0x160
[ 57.369941] __x64_sys_pread64+0x6e/0xa0
[ 57.369946] ? lockdep_hardirqs_on+0x79/0x100
[ 57.369958] do_syscall_64+0x3a/0x70
[ 57.369965] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 57.369973] RIP: 0033:0x7f7ed4c1399f
[ 57.369979] Code: 08 89 3c 24 48 89 4c 24 18 e8 7d f3 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 48 8b 74 24 08 8b 3c 24 b8 11 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 04 24 e8 cd f3 ff ff 48 8b
[ 57.369983] RSP: 002b:00007ffd7918c580 EFLAGS: 00000293 ORIG_RAX: 0000000000000011
[ 57.369990] RAX: ffffffffffffffda RBX: 00000000015b4540 RCX: 00007f7ed4c1399f
[ 57.369993] RDX: 0000000000001000 RSI: 00000000015de000 RDI: 0000000000000009
[ 57.369996] RBP: 00000000015b4540 R08: 0000000000000000 R09: 0000000000000001
[ 57.369999] R10: 0000000000e5c000 R11: 0000000000000293 R12: 00007f7eb5269a70
[ 57.370002] R13: 0000000000000000 R14: 0000000000001000 R15: 00000000015b4568
[ 57.370031] CPU: 7 PID: 1507 Comm: fio Not tainted 5.13.0-rc1+ #34
[ 57.370036] Hardware name: System manufacturer System Product Name/PRIME Z270-A, BIOS 1302 03/15/2018
[ 57.370039] Call Trace:
[ 57.370045] dump_stack+0x6d/0x89
[ 57.370056] check_preemption_disabled+0xc8/0xd0
[ 57.370068] __target_init_cmd+0x157/0x170 [target_core_mod]
[ 57.370121] target_init_cmd+0x76/0x90 [target_core_mod]
[ 57.370178] tcm_loop_queuecommand+0x109/0x210 [tcm_loop]
[ 57.370197] scsi_queue_rq+0x38e/0xc40
[ 57.370224] __blk_mq_try_issue_directly+0x109/0x1c0
...
[2]
[ 117.458597] BUG: using smp_processor_id() in preemptible [00000000] code: kworker/u16:8
[ 117.467279] caller is __target_init_cmd+0x157/0x170 [target_core_mod]
[ 117.473893] CPU: 1 PID: 418 Comm: kworker/u16:6 Not tainted 5.13.0-rc1+ #34
[ 117.481150] Hardware name: System manufacturer System Product Name/PRIME Z270-A, BIOS 8
[ 117.481153] Workqueue: scsi_tmf_7 scmd_eh_abort_handler
[ 117.481156] Call Trace:
[ 117.481158] dump_stack+0x6d/0x89
[ 117.481162] check_preemption_disabled+0xc8/0xd0
[ 117.512575] target_submit_tmr+0x41/0x150 [target_core_mod]
[ 117.519705] tcm_loop_issue_tmr+0xa7/0x100 [tcm_loop]
[ 117.524913] tcm_loop_abort_task+0x43/0x60 [tcm_loop]
[ 117.530137] scmd_eh_abort_handler+0x7b/0x230
[ 117.534681] process_one_work+0x268/0x580
[ 117.538862] worker_thread+0x55/0x3b0
[ 117.542652] ? process_one_work+0x580/0x580
[ 117.548351] kthread+0x143/0x160
[ 117.551675] ? kthread_create_worker_on_cpu+0x40/0x40
[ 117.556873] ret_from_fork+0x1f/0x30
Link: https://lore.kernel.org/r/20210515070315.215801-1-shinichiro.kawasaki@wdc.com
Fixes: 1526d9f10c61 ("scsi: target: Make state_list per CPU")
Cc: stable@vger.kernel.org # v5.11+
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When driver is loaded after rmmod some drives are not showing up during
discovery.
SATA drives are directly attached to the controller connected phys. During
device discovery, the IDENTIFY command (qc timeout (cmd 0xec)) is timing out
during revalidation. This will trigger abort from host side and controller
successfully aborts the command and returns success. Post this successful
abort response ATA library decides to mark the disk as NODEV.
To overcome this, inside pm8001_scan_start() after phy_start() call, add get
start response and wait for few milliseconds to trigger next phy start.
This millisecond delay will give sufficient time for the controller state
machine to accept next phy start.
Link: https://lore.kernel.org/r/20210505120103.24497-1-ajish.koshy@microchip.com
Signed-off-by: Ajish Koshy <ajish.koshy@microchip.com>
Signed-off-by: Viswas G <viswas.g@microchip.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Fix to return a negative error code from the error handling case instead of
0 as done elsewhere in this function.
Link: https://lore.kernel.org/r/20210514090952.6715-1-thunder.leizhen@huawei.com
Fixes: a9083016a531 ("[SCSI] qla2xxx: Add ISP82XX support.")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following trace was observed:
[ 14.042059] Call Trace:
[ 14.042061] <IRQ>
[ 14.042068] qedf_link_update+0x144/0x1f0 [qedf]
[ 14.042117] qed_link_update+0x5c/0x80 [qed]
[ 14.042135] qed_mcp_handle_link_change+0x2d2/0x410 [qed]
[ 14.042155] ? qed_set_ptt+0x70/0x80 [qed]
[ 14.042170] ? qed_set_ptt+0x70/0x80 [qed]
[ 14.042186] ? qed_rd+0x13/0x40 [qed]
[ 14.042205] qed_mcp_handle_events+0x437/0x690 [qed]
[ 14.042221] ? qed_set_ptt+0x70/0x80 [qed]
[ 14.042239] qed_int_sp_dpc+0x3a6/0x3e0 [qed]
[ 14.042245] tasklet_action_common.isra.14+0x5a/0x100
[ 14.042250] __do_softirq+0xe4/0x2f8
[ 14.042253] irq_exit+0xf7/0x100
[ 14.042255] do_IRQ+0x7f/0xd0
[ 14.042257] common_interrupt+0xf/0xf
[ 14.042259] </IRQ>
API qedf_link_update() is getting called from QED but by that time
shost_data is not initialised. This results in a NULL pointer dereference
when we try to dereference shost_data while updating supported_speeds.
Add a NULL pointer check before dereferencing shost_data.
Link: https://lore.kernel.org/r/20210512072533.23618-1-jhasan@marvell.com
Fixes: 61d8658b4a43 ("scsi: qedf: Add QLogic FastLinQ offload FCoE driver framework.")
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Javed Hasan <jhasan@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
With the current implementation of the UFS driver active_queues is 1
instead of 0 if all UFS request queues are idle. That causes
hctx_may_queue() to divide the queue depth by 2 when queueing a request and
hence reduces the usable queue depth.
The shared tag set code in the block layer keeps track of the number of
active request queues. blk_mq_tag_busy() is called before a request is
queued onto a hwq and blk_mq_tag_idle() is called some time after the hwq
became idle. blk_mq_tag_idle() is called from inside blk_mq_timeout_work().
Hence, blk_mq_tag_idle() is only called if a timer is associated with each
request that is submitted to a request queue that shares a tag set with
another request queue.
Adds a blk_mq_start_request() call in ufshcd_exec_dev_cmd(). This doubles
the queue depth on my test setup from 16 to 32.
In addition to increasing the usable queue depth, also fix the
documentation of the 'timeout' parameter in the header above
ufshcd_exec_dev_cmd().
Link: https://lore.kernel.org/r/20210513164912.5683-1-bvanassche@acm.org
Fixes: 7252a3603015 ("scsi: ufs: Avoid busy-waiting by eliminating tag conflicts")
Cc: Can Guo <cang@codeaurora.org>
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Bean Huo <beanhuo@micron.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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