[SCSI] BusLogic: Fix an oops when intializing multimaster adapter

This fixes an oops caused by buslogic driver when initializing a BusLogic
MultiMaster adapter. Initialization code used scope of a variable
incorrectly which created a NULL pointer. Oops message is below:

BUG: unable to handle kernel NULL pointer dereference at 0000000c
IP: [<c150c137>] blogic_init_mm_probeinfo.isra.17+0x20a/0x583
*pde = 00000000
Oops: 002 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 3.11.1.puz1 #1
Hardware name:    /Canterwood, BIOS 6.00 PG 05/16/2003
task: f7050000 ti: f7054000 task.ti: f7054000
EIP: 0060:[<c150c137>] EFLAGS: 00010246 CPU:1
EIP is at blogic_init_mm_probeinfo.isra.17+0x20a/0x583
EAX: 00000013 EBX: 00000000 ECX: 00000000 EDX: f8001000
ESI: f71cb800 EDI: f7388000 EBP: 00007800 ESP: f7055c84
 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
CR0: 8005003b CR2: 0000000c CR3: 0154f000 CR4: 000007d0
Stack:
 0000001c 00000000 c11a59f6 f7055c98 00008130 ffffffff ffffffff 00000000
 00000003 00000000 00000000 00000000 00000013 f8001000 00000001 000003d0
 00000000 00000000 00000000 c14e3f84 f78803c8 00000000 f738c000 000000e9
Call Trace:
 [<c11a59f6>] ? pci_get_subsys+0x33/0x38
 [<c150c4fb>] ? blogic_init_probeinfo_list+0x4b/0x19e
 [<c108d593>] ? __alloc_pages_nodemask+0xe3/0x623
 [<c108d593>] ? __alloc_pages_nodemask+0xe3/0x623
 [<c10fb99e>] ? sysfs_link_sibling+0x61/0x8d
 [<c10b0519>] ? kmem_cache_alloc+0x8b/0xb5
 [<c150cce5>] ? blogic_init+0xa1/0x10e8
 [<c10fc0a8>] ? sysfs_add_one+0x10/0x9d
 [<c10fc18a>] ? sysfs_addrm_finish+0x12/0x85
 [<c10fca37>] ? sysfs_do_create_link_sd+0x9d/0x1b4
 [<c117c272>] ? blk_register_queue+0x69/0xb3
 [<c10fcb68>] ? sysfs_create_link+0x1a/0x2c
 [<c1181a07>] ? add_disk+0x1a1/0x3c7
 [<c138737b>] ? klist_next+0x60/0xc3
 [<c122cc3a>] ? scsi_dh_detach+0x68/0x68
 [<c1213e36>] ? bus_for_each_dev+0x51/0x61
 [<c1000356>] ? do_one_initcall+0x22/0x12c
 [<c10f3688>] ? __proc_create+0x8c/0xba
 [<c150cc44>] ? blogic_setup+0x5f6/0x5f6
 [<c14e94aa>] ? repair_env_string+0xf/0x4d
 [<c14e949b>] ? do_early_param+0x71/0x71
 [<c103efaa>] ? parse_args+0x21f/0x33d
 [<c14e9a54>] ? kernel_init_freeable+0xdf/0x17d
 [<c14e949b>] ? do_early_param+0x71/0x71
 [<c1388b64>] ? kernel_init+0x8/0xc0
 [<c1392222>] ? ret_from_kernel_thread+0x6/0x28
 [<c1392227>] ? ret_from_kernel_thread+0x1b/0x28
 [<c1388b5c>] ? rest_init+0x6c/0x6c
Code: 89 44 24 10 0f b6 44 24 3d 89 44 24 0c c7 44 24 08 00 00 00 00 c7 44 24 04 38 62 46 c1 c7 04 24 02 00 00 00 e8 78 13 d2 ff 31 db <89> 6b 0c b0 20 89 ea ee
 c7 44 24 08 04 00 00 00 8d 44 24 4c 89
EIP: [<c150c137>] blogic_init_mm_probeinfo.isra.17+0x20a/0x583 SS:ESP 0068:f7055c84
CR2: 000000000000000c
---[ end trace 17f45f5196d40487 ]---
Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009

Signed-off-by: Khalid Aziz <khalid.aziz@oracle.com>
Cc: <stable@vger.kernel.org> # 3.11.x
Reported-by: Pierre Uszynski <pierre@rahul.net>
Tested-by: Pierre Uszynski <pierre@rahul.net>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
[SCSI] qla2xxx: Fix request queue null dereference.

If an invalid IOCB is returned on the response queue then the index into the
request queue map could be invalid and could return to us a bogus value. This
could cause us to try to deference an invalid pointer and cause an exception.

If we encounter this condition, simply return as no context can be established
for this response.

Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
[SCSI] sd: call blk_pm_runtime_init before add_disk

Sujit has found a race condition that would make q->nr_pending
unbalanced, it occurs as Sujit explained:

"
sd_probe_async() ->
	add_disk() ->
		disk_add_event() ->
			schedule(disk_events_workfn)
	sd_revalidate_disk()
	blk_pm_runtime_init()
return;

Let's say the disk_events_workfn() calls sd_check_events() which tries
to send test_unit_ready() and because of sd_revalidate_disk() trying to
send another commands the test_unit_ready() might be re-queued as the
tagged command queuing is disabled.

So the race condition is -

Thread 1 			  |		Thread 2
sd_revalidate_disk()		  |	sd_check_events()
...nr_pending = 0 as q->dev = NULL|	scsi_queue_insert()
blk_runtime_pm_init()		  | 	blk_pm_requeue_request() ->
				  |	nr_pending = -1 since
				  |	q->dev != NULL
"

The problem is, the test_unit_ready request doesn't get counted the
first time it is queued, so the later decrement of q->nr_pending in
blk_pm_requeue_request makes it unbalanced.

Fix this by calling blk_pm_runtime_init before add_disk so that all
requests initiated there will all be counted.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Reported-and-tested-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
md: Fix skipping recovery for read-only arrays.

Since:
        commit 7ceb17e87bde79d285a8b988cfed9eaeebe60b86
        md: Allow devices to be re-added to a read-only array.

spares are activated on a read-only array. In case of raid1 and raid10
personalities it causes that not-in-sync devices are marked in-sync
without checking if recovery has been finished.

If a read-only array is degraded and one of its devices is not in-sync
(because the array has been only partially recovered) recovery will be skipped.

This patch adds checking if recovery has been finished before marking a device
in-sync for raid1 and raid10 personalities. In case of raid5 personality
such condition is already present (at raid5.c:6029).

Bug was introduced in 3.10 and causes data corruption.

Cc: stable@vger.kernel.org
Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
md: avoid deadlock when md_set_badblocks.

When operate harddisk and hit errors, md_set_badblocks is called after
scsi_restart_operations which already disabled the irq. but md_set_badblocks
will call write_sequnlock_irq and enable irq. so softirq can preempt the
current thread and that may cause a deadlock. I think this situation should
use write_sequnlock_irqsave/irqrestore instead.

I met the situation and the call trace is below:
[  638.919974] BUG: spinlock recursion on CPU#0, scsi_eh_13/1010
[  638.921923]  lock: 0xffff8800d4d51fc8, .magic: dead4ead, .owner: scsi_eh_13/1010, .owner_cpu: 0
[  638.923890] CPU: 0 PID: 1010 Comm: scsi_eh_13 Not tainted 3.12.0-rc5+ #37
[  638.925844] Hardware name: To be filled by O.E.M. To be filled by O.E.M./MAHOBAY, BIOS 4.6.5 03/05/2013
[  638.927816]  ffff880037ad4640 ffff880118c03d50 ffffffff8172ff85 0000000000000007
[  638.929829]  ffff8800d4d51fc8 ffff880118c03d70 ffffffff81730030 ffff8800d4d51fc8
[  638.931848]  ffffffff81a72eb0 ffff880118c03d90 ffffffff81730056 ffff8800d4d51fc8
[  638.933884] Call Trace:
[  638.935867]  <IRQ>  [<ffffffff8172ff85>] dump_stack+0x55/0x76
[  638.937878]  [<ffffffff81730030>] spin_dump+0x8a/0x8f
[  638.939861]  [<ffffffff81730056>] spin_bug+0x21/0x26
[  638.941836]  [<ffffffff81336de4>] do_raw_spin_lock+0xa4/0xc0
[  638.943801]  [<ffffffff8173f036>] _raw_spin_lock+0x66/0x80
[  638.945747]  [<ffffffff814a73ed>] ? scsi_device_unbusy+0x9d/0xd0
[  638.947672]  [<ffffffff8173fb1b>] ? _raw_spin_unlock+0x2b/0x50
[  638.949595]  [<ffffffff814a73ed>] scsi_device_unbusy+0x9d/0xd0
[  638.951504]  [<ffffffff8149ec47>] scsi_finish_command+0x37/0xe0
[  638.953388]  [<ffffffff814a75e8>] scsi_softirq_done+0xa8/0x140
[  638.955248]  [<ffffffff8130e32b>] blk_done_softirq+0x7b/0x90
[  638.957116]  [<ffffffff8104fddd>] __do_softirq+0xfd/0x330
[  638.958987]  [<ffffffff810b964f>] ? __lock_release+0x6f/0x100
[  638.960861]  [<ffffffff8174a5cc>] call_softirq+0x1c/0x30
[  638.962724]  [<ffffffff81004c7d>] do_softirq+0x8d/0xc0
[  638.964565]  [<ffffffff8105024e>] irq_exit+0x10e/0x150
[  638.966390]  [<ffffffff8174ad4a>] smp_apic_timer_interrupt+0x4a/0x60
[  638.968223]  [<ffffffff817499af>] apic_timer_interrupt+0x6f/0x80
[  638.970079]  <EOI>  [<ffffffff810b964f>] ? __lock_release+0x6f/0x100
[  638.971899]  [<ffffffff8173fa6a>] ? _raw_spin_unlock_irq+0x3a/0x50
[  638.973691]  [<ffffffff8173fa60>] ? _raw_spin_unlock_irq+0x30/0x50
[  638.975475]  [<ffffffff81562393>] md_set_badblocks+0x1f3/0x4a0
[  638.977243]  [<ffffffff81566e07>] rdev_set_badblocks+0x27/0x80
[  638.978988]  [<ffffffffa00d97bb>] raid5_end_read_request+0x36b/0x4e0 [raid456]
[  638.980723]  [<ffffffff811b5a1d>] bio_endio+0x1d/0x40
[  638.982463]  [<ffffffff81304ff3>] req_bio_endio.isra.65+0x83/0xa0
[  638.984214]  [<ffffffff81306b9f>] blk_update_request+0x7f/0x350
[  638.985967]  [<ffffffff81306ea1>] blk_update_bidi_request+0x31/0x90
[  638.987710]  [<ffffffff813085e0>] __blk_end_bidi_request+0x20/0x50
[  638.989439]  [<ffffffff8130862f>] __blk_end_request_all+0x1f/0x30
[  638.991149]  [<ffffffff81308746>] blk_peek_request+0x106/0x250
[  638.992861]  [<ffffffff814a62a9>] ? scsi_kill_request.isra.32+0xe9/0x130
[  638.994561]  [<ffffffff814a633a>] scsi_request_fn+0x4a/0x3d0
[  638.996251]  [<ffffffff813040a7>] __blk_run_queue+0x37/0x50
[  638.997900]  [<ffffffff813045af>] blk_run_queue+0x2f/0x50
[  638.999553]  [<ffffffff814a5750>] scsi_run_queue+0xe0/0x1c0
[  639.001185]  [<ffffffff814a7721>] scsi_run_host_queues+0x21/0x40
[  639.002798]  [<ffffffff814a2e87>] scsi_restart_operations+0x177/0x200
[  639.004391]  [<ffffffff814a4fe9>] scsi_error_handler+0xc9/0xe0
[  639.005996]  [<ffffffff814a4f20>] ? scsi_unjam_host+0xd0/0xd0
[  639.007600]  [<ffffffff81072f6b>] kthread+0xdb/0xe0
[  639.009205]  [<ffffffff81072e90>] ? flush_kthread_worker+0x170/0x170
[  639.010821]  [<ffffffff81748cac>] ret_from_fork+0x7c/0xb0
[  639.012437]  [<ffffffff81072e90>] ? flush_kthread_worker+0x170/0x170

This bug was introduce in commit  2e8ac30312973dd20e68073653
(the first time rdev_set_badblock was call from interrupt context),
so this patch is appropriate for 3.5 and subsequent kernels.

Cc: <stable@vger.kernel.org> (3.5+)
Signed-off-by: Bian Yu <bianyu@kedacom.com>
Reviewed-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
raid5: set bio bi_vcnt 0 for discard request

SCSI layer will add new payload for discard request. If two bios are merged
to one, the second bio has bi_vcnt 1 which is set in raid5. This will confuse
SCSI and cause oops.

Suitable for backport to 3.7+

Cc: stable@vger.kernel.org (v3.7+)
Reported-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
raid5: avoid finding "discard" stripe

SCSI discard will damage discard stripe bio setting, eg, some fields are
changed. If the stripe is reused very soon, we have wrong bios setting. We
remove discard stripe from hash list, so next time the strip will be fully
initialized.

Suitable for backport to 3.7+.

Cc: <stable@vger.kernel.org> (3.7+)
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "This is a set of two fixes which cause oopses (Buslogic, qla2xxx) and
 one fix which may cause a hang because of request miscounting (sd)"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  [SCSI] sd: call blk_pm_runtime_init before add_disk
  [SCSI] qla2xxx: Fix request queue null dereference.
  [SCSI] BusLogic: Fix an oops when intializing multimaster adapter
Merge tag 'md/3.12-fixes' of git://neil.brown.name/md

Pull md bugfixes from Neil Brown:
 "Assorted md bug-fixes for 3.12.

  All tagged for -stable releases too"

* tag 'md/3.12-fixes' of git://neil.brown.name/md:
  raid5: avoid finding "discard" stripe
  raid5: set bio bi_vcnt 0 for discard request
  md: avoid deadlock when md_set_badblocks.
  md: Fix skipping recovery for read-only arrays.