Add a new include/linux/raid/detect.h header to declare the
md_autodetect_dev prototype which can be shared between md and
the partition code.  Then use IS_BUILTIN to call it instead of the
ifdef magic.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

read_dev_sector and put_dev_sector are now only used by the partition
parsing code.  Remove the export for read_dev_sector and merge it into
the only caller.  Clean the mess up a bit by using goto labels and
the SECTOR_SHIFT constant.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Call scsi_bios_ptable from scsi_partsize instead of requiring boilerplate
code in the callers.  Also switch the calling convention to match that
of the ->bios_param instances calling this function, and use true/false
for the return value instead of the weird -1 convention.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This avoids the need for a forward declaration and generally keeps the
file in the lower level first, high level last order.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Use read_mapping_page and kmemdup instead of the odd read_dev_sector and
put_dev_sector helpers from the partitioning code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

There isn't any good reason not to simply open code the allocation and
freeing of the partition_meta_info structure.  Especially as one of
the branches in alloc_part_info is entirely dead code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Move the sysfs _show methods that are used both on the full disk and
partition nodes to genhd.c instead of hiding them in the partitioning
code.  Also move the declaration for these methods to block/blk.h so
that we don't expose them to drivers.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Thes functions aren't really related to partition support, so move them
to a more suitable place.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

There is no good reason for __bdevname to exist.  Just open code
printing the string in the callers.  For three of them the format
string can be trivially merged into existing printk statements,
and in init/do_mounts.c we can at least do the scnprintf once at
the start of the function, and unconditional of CONFIG_BLOCK to
make the output for tiny configfs a little more helpful.

Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This function is only used by init/do_mounts.c, which can't be modular.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

In bfq_pd_offline(), the function bfq_flush_idle_tree() is invoked to
flush the rb tree that contains all idle entities belonging to the pd
(cgroup) being destroyed. In particular, bfq_flush_idle_tree() is
invoked before bfq_reparent_active_queues(). Yet the latter may happen
to add some entities to the idle tree. It happens if, in some of the
calls to bfq_bfqq_move() performed by bfq_reparent_active_queues(),
the queue to move is empty and gets expired.

This commit simply reverses the invocation order between
bfq_flush_idle_tree() and bfq_reparent_active_queues().

Tested-by: cki-project@redhat.com
Signed-off-by: NPaolo Valente <paolo.valente@linaro.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

bfq_reparent_leaf_entity() reparents the input leaf entity (a leaf
entity represents just a bfq_queue in an entity tree). Yet, the input
entity is guaranteed to always be a leaf entity only in two-level
entity trees. In this respect, because of the error fixed by
commit 14afc593 ("block, bfq: fix overwrite of bfq_group pointer
in bfq_find_set_group()"), all (wrongly collapsed) entity trees happened
to actually have only two levels. After the latter commit, this does not
hold any longer.

This commit fixes this problem by modifying
bfq_reparent_leaf_entity(), so that it searches an active leaf entity
down the path that stems from the input entity. Such a leaf entity is
guaranteed to exist when bfq_reparent_leaf_entity() is invoked.

Tested-by: cki-project@redhat.com
Signed-off-by: NPaolo Valente <paolo.valente@linaro.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

A bfq_put_queue() may be invoked in __bfq_bic_change_cgroup(). The
goal of this put is to release a process reference to a bfq_queue. But
process-reference releases may trigger also some extra operation, and,
to this goal, are handled through bfq_release_process_ref(). So, turn
the invocation of bfq_put_queue() into an invocation of
bfq_release_process_ref().

Tested-by: cki-project@redhat.com
Signed-off-by: NPaolo Valente <paolo.valente@linaro.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Commit ecedd3d7 ("block, bfq: get extra ref to prevent a queue
from being freed during a group move") gets an extra reference to a
bfq_queue before possibly deactivating it (temporarily), in
bfq_bfqq_move(). This prevents the bfq_queue from disappearing before
being reactivated in its new group.

Yet, the bfq_queue may also be expired (i.e., its service may be
stopped) before the bfq_queue is deactivated. And also an expiration
may lead to a premature freeing. This commit fixes this issue by
simply moving forward the getting of the extra reference already
introduced by commit ecedd3d7 ("block, bfq: get extra ref to
prevent a queue from being freed during a group move").

Reported-by: cki-project@redhat.com
Tested-by: cki-project@redhat.com
Signed-off-by: NPaolo Valente <paolo.valente@linaro.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

In bfq_idle_slice_timer func, bfqq = bfqd->in_service_queue is
not in bfqd-lock critical section. The bfqq, which is not
equal to NULL in bfq_idle_slice_timer, may be freed after passing
to bfq_idle_slice_timer_body. So we will access the freed memory.

In addition, considering the bfqq may be in race, we should
firstly check whether bfqq is in service before doing something
on it in bfq_idle_slice_timer_body func. If the bfqq in race is
not in service, it means the bfqq has been expired through
__bfq_bfqq_expire func, and wait_request flags has been cleared in
__bfq_bfqd_reset_in_service func. So we do not need to re-clear the
wait_request of bfqq which is not in service.

KASAN log is given as follows:
[13058.354613] ==================================================================
[13058.354640] BUG: KASAN: use-after-free in bfq_idle_slice_timer+0xac/0x290
[13058.354644] Read of size 8 at addr ffffa02cf3e63f78 by task fork13/19767
[13058.354646]
[13058.354655] CPU: 96 PID: 19767 Comm: fork13
[13058.354661] Call trace:
[13058.354667]  dump_backtrace+0x0/0x310
[13058.354672]  show_stack+0x28/0x38
[13058.354681]  dump_stack+0xd8/0x108
[13058.354687]  print_address_description+0x68/0x2d0
[13058.354690]  kasan_report+0x124/0x2e0
[13058.354697]  __asan_load8+0x88/0xb0
[13058.354702]  bfq_idle_slice_timer+0xac/0x290
[13058.354707]  __hrtimer_run_queues+0x298/0x8b8
[13058.354710]  hrtimer_interrupt+0x1b8/0x678
[13058.354716]  arch_timer_handler_phys+0x4c/0x78
[13058.354722]  handle_percpu_devid_irq+0xf0/0x558
[13058.354731]  generic_handle_irq+0x50/0x70
[13058.354735]  __handle_domain_irq+0x94/0x110
[13058.354739]  gic_handle_irq+0x8c/0x1b0
[13058.354742]  el1_irq+0xb8/0x140
[13058.354748]  do_wp_page+0x260/0xe28
[13058.354752]  __handle_mm_fault+0x8ec/0x9b0
[13058.354756]  handle_mm_fault+0x280/0x460
[13058.354762]  do_page_fault+0x3ec/0x890
[13058.354765]  do_mem_abort+0xc0/0x1b0
[13058.354768]  el0_da+0x24/0x28
[13058.354770]
[13058.354773] Allocated by task 19731:
[13058.354780]  kasan_kmalloc+0xe0/0x190
[13058.354784]  kasan_slab_alloc+0x14/0x20
[13058.354788]  kmem_cache_alloc_node+0x130/0x440
[13058.354793]  bfq_get_queue+0x138/0x858
[13058.354797]  bfq_get_bfqq_handle_split+0xd4/0x328
[13058.354801]  bfq_init_rq+0x1f4/0x1180
[13058.354806]  bfq_insert_requests+0x264/0x1c98
[13058.354811]  blk_mq_sched_insert_requests+0x1c4/0x488
[13058.354818]  blk_mq_flush_plug_list+0x2d4/0x6e0
[13058.354826]  blk_flush_plug_list+0x230/0x548
[13058.354830]  blk_finish_plug+0x60/0x80
[13058.354838]  read_pages+0xec/0x2c0
[13058.354842]  __do_page_cache_readahead+0x374/0x438
[13058.354846]  ondemand_readahead+0x24c/0x6b0
[13058.354851]  page_cache_sync_readahead+0x17c/0x2f8
[13058.354858]  generic_file_buffered_read+0x588/0xc58
[13058.354862]  generic_file_read_iter+0x1b4/0x278
[13058.354965]  ext4_file_read_iter+0xa8/0x1d8 [ext4]
[13058.354972]  __vfs_read+0x238/0x320
[13058.354976]  vfs_read+0xbc/0x1c0
[13058.354980]  ksys_read+0xdc/0x1b8
[13058.354984]  __arm64_sys_read+0x50/0x60
[13058.354990]  el0_svc_common+0xb4/0x1d8
[13058.354994]  el0_svc_handler+0x50/0xa8
[13058.354998]  el0_svc+0x8/0xc
[13058.354999]
[13058.355001] Freed by task 19731:
[13058.355007]  __kasan_slab_free+0x120/0x228
[13058.355010]  kasan_slab_free+0x10/0x18
[13058.355014]  kmem_cache_free+0x288/0x3f0
[13058.355018]  bfq_put_queue+0x134/0x208
[13058.355022]  bfq_exit_icq_bfqq+0x164/0x348
[13058.355026]  bfq_exit_icq+0x28/0x40
[13058.355030]  ioc_exit_icq+0xa0/0x150
[13058.355035]  put_io_context_active+0x250/0x438
[13058.355038]  exit_io_context+0xd0/0x138
[13058.355045]  do_exit+0x734/0xc58
[13058.355050]  do_group_exit+0x78/0x220
[13058.355054]  __wake_up_parent+0x0/0x50
[13058.355058]  el0_svc_common+0xb4/0x1d8
[13058.355062]  el0_svc_handler+0x50/0xa8
[13058.355066]  el0_svc+0x8/0xc
[13058.355067]
[13058.355071] The buggy address belongs to the object at ffffa02cf3e63e70#012 which belongs to the cache bfq_queue of size 464
[13058.355075] The buggy address is located 264 bytes inside of#012 464-byte region [ffffa02cf3e63e70, ffffa02cf3e64040)
[13058.355077] The buggy address belongs to the page:
[13058.355083] page:ffff7e80b3cf9800 count:1 mapcount:0 mapping:ffff802db5c90780 index:0xffffa02cf3e606f0 compound_mapcount: 0
[13058.366175] flags: 0x2ffffe0000008100(slab|head)
[13058.370781] raw: 2ffffe0000008100 ffff7e80b53b1408 ffffa02d730c1c90 ffff802db5c90780
[13058.370787] raw: ffffa02cf3e606f0 0000000000370023 00000001ffffffff 0000000000000000
[13058.370789] page dumped because: kasan: bad access detected
[13058.370791]
[13058.370792] Memory state around the buggy address:
[13058.370797]  ffffa02cf3e63e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fb fb
[13058.370801]  ffffa02cf3e63e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[13058.370805] >ffffa02cf3e63f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[13058.370808]                                                                 ^
[13058.370811]  ffffa02cf3e63f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[13058.370815]  ffffa02cf3e64000: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[13058.370817] ==================================================================
[13058.370820] Disabling lock debugging due to kernel taint

Here, we directly pass the bfqd to bfq_idle_slice_timer_body func.
--
V2->V3: rewrite the comment as suggested by Paolo Valente
V1->V2: add one comment, and add Fixes and Reported-by tag.

Fixes: aee69d78 ("block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler")
Acked-by: NPaolo Valente <paolo.valente@linaro.org>
Reported-by: NWang Wang <wangwang2@huawei.com>
Signed-off-by: NZhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: NFeilong Lin <linfeilong@huawei.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

block/genhd provides set_capacity_revalidate_and_notify() for sending RESIZE
notifications via uevents. This notification is newly added to scsi sd.
Signed-off-by: NBalbir Singh <sblbir@amazon.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

block/genhd provides set_capacity_revalidate_and_notify() for
sending RESIZE notifications via uevents. This notification is
newly added to NVME devices
Signed-off-by: NBalbir Singh <sblbir@amazon.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

block/genhd provides set_capacity_revalidate_and_notify() for
sending RESIZE notifications via uevents.
Signed-off-by: NBalbir Singh <sblbir@amazon.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

block/genhd provides set_capacity_revalidate_and_notify() for sending RESIZE
notifications via uevents.
Signed-off-by: NBalbir Singh <sblbir@amazon.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Allow block/genhd to notify user space (via udev) about disk size changes
using a new helper set_capacity_revalidate_and_notify(), which is a wrapper
on top of set_capacity(). set_capacity_revalidate_and_notify() will only
notify via udev if the current capacity or the target capacity is not zero
and iff the capacity changes.
Suggested-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NSomeswarudu Sangaraju <ssomesh@amazon.com>
Signed-off-by: NBalbir Singh <sblbir@amazon.com>
Reviewed-by: NBob Liu <bob.liu@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

submit_bio_wait() can be called from ioctl(BLKSECDISCARD), which
may take long time to complete, as Salman mentioned, 4K BLKSECDISCARD
takes up to 100 second on some devices. Also any block I/O operation
that occurs after the BLKSECDISCARD is submitted will also potentially
be affected by the hung task timeouts.

Another report is that task hang can be observed when running mkfs
over raid10 which takes a small max discard sectors limit because
of chunk size.

So prevent hung_check from firing by taking same approach used
in blk_execute_rq(), and the wake-up interval is set as half the
hung_check timer period, which keeps overhead low enough.

Cc: Salman Qazi <sqazi@google.com>
Cc: Jesse Barnes <jsbarnes@google.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Link: https://lkml.org/lkml/2020/2/12/1193Reported-by: NSalman Qazi <sqazi@google.com>
Reviewed-by: NJesse Barnes <jsbarnes@google.com>
Reviewed-by: NSalman Qazi <sqazi@google.com>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Historically we only set the capacity to zero for devices that support
partitions (independ of actually having partitions created).  Doing that
is rather inconsistent, but changing it broke legacy udisks polling for
legacy ide-cdrom devices.  Use the crude a crude check for devices that
either are non-removable or partitionable to get the sane behavior for
most device while not breaking userspace for this particular setup.

Fixes: a1548b67 ("block: move rescan_partitions to fs/block_dev.c")
Reported-by: NHe Zhe <zhe.he@windriver.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Tested-by: NHe Zhe <zhe.he@windriver.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Check for overflow in addition before checking for end-of-block-device.

Steps to reproduce:

	#define _GNU_SOURCE 1
	#include <sys/ioctl.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <fcntl.h>

	typedef unsigned long long __u64;

	struct blk_zone_range {
	        __u64 sector;
	        __u64 nr_sectors;
	};

	#define BLKRESETZONE    _IOW(0x12, 131, struct blk_zone_range)

	int main(void)
	{
	        int fd = open("/dev/nullb0", O_RDWR|O_DIRECT);
	        struct blk_zone_range zr = {4096, 0xfffffffffffff000ULL};
	        ioctl(fd, BLKRESETZONE, &zr);
	        return 0;
	}

BUG: KASAN: null-ptr-deref in submit_bio_wait+0x74/0xe0
Write of size 8 at addr 0000000000000040 by task a.out/1590

CPU: 8 PID: 1590 Comm: a.out Not tainted 5.6.0-rc1-00019-g359c92c0 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190711_202441-buildvm-armv7-10.arm.fedoraproject.org-2.fc31 04/01/2014
Call Trace:
 dump_stack+0x76/0xa0
 __kasan_report.cold+0x5/0x3e
 kasan_report+0xe/0x20
 submit_bio_wait+0x74/0xe0
 blkdev_zone_mgmt+0x26f/0x2a0
 blkdev_zone_mgmt_ioctl+0x14b/0x1b0
 blkdev_ioctl+0xb28/0xe60
 block_ioctl+0x69/0x80
 ksys_ioctl+0x3af/0xa50
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAlexey Dobriyan (SK hynix) <adobriyan@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NWeiping Zhang <zhangweiping@didiglobal.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch changes the check condition for the validity/authentication
of the session.

1. The Host Session Number(HSN) in the response should match the HSN for
   the session.
2. The TPER Session Number(TSN) can never be less than 4096 for a regular
   session.

Reference:
Section 3.2.2.1   of https://trustedcomputinggroup.org/wp-content/uploads/TCG_Storage_Opal_SSC_Application_Note_1-00_1-00-Final.pdf
Section 3.3.7.1.1 of https://trustedcomputinggroup.org/wp-content/uploads/TCG_Storage_Architecture_Core_Spec_v2.01_r1.00.pdfCo-developed-by: NAndrzej Jakowski <andrzej.jakowski@linux.intel.com>
Signed-off-by: NAndrzej Jakowski <andrzej.jakowski@linux.intel.com>
Signed-off-by: NRevanth Rajashekar <revanth.rajashekar@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The kernel documentation includes a brief section about genhd
capabilities, but it turns out that the only documented
capability (GENHD_FL_MEDIA_CHANGE_NOTIFY) isn't used any more.

This patch removes that flag, and documents the rest, based on my
understanding of the current uses of these flags in the kernel. The
documentation is kept in the header file, alongside the declarations,
in the hope that it will be kept up-to-date in future; the kernel
documentation is changed to include the documentation generated from
the header file.

Because the ultimate goal is to provide some end-user
documentation (or end-administrator documentation), the comments are
perhaps more user-oriented than might be expected. Since the values
are shown to users in hexadecimal, the documentation lists them in
hexadecimal, and the constant declarations are adjusted to match.
Reviewed-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NStephen Kitt <steve@sk2.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Remove the comment about return value, since it is not valid after
commit 404b8f5a ("block: cleanup kick/queued handling").
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Remove 'q' from arguments since it is not used anymore after
commit 7e992f84 ("block: remove non mq parts from the
flush code").
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Both cmd and sense had been moved to scsi_request, so remove
the related comments to avoid confusion.

And as Bart suggested, move _blk_rq_prep_clone into the only
caller (blk_rq_prep_clone).
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Previously, blk_cleanup_queue has called blk_set_queue_dying to set the
flag, no need to do it again.
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Use the two functions to simplify code.
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Since the later description mentioned "checked against the new queue
limits", so make the change to avoid confusion.
Signed-off-by: NGuoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

There is a potential race between ioc_release_fn() and
ioc_clear_queue() as shown below, due to which below kernel
crash is observed. It also can result into use-after-free
issue.

context#1:				context#2:
ioc_release_fn()			__ioc_clear_queue() gets the same icq
->spin_lock(&ioc->lock);		->spin_lock(&ioc->lock);
->ioc_destroy_icq(icq);
  ->list_del_init(&icq->q_node);
  ->call_rcu(&icq->__rcu_head,
  	icq_free_icq_rcu);
->spin_unlock(&ioc->lock);
					->ioc_destroy_icq(icq);
					  ->hlist_del_init(&icq->ioc_node);
					  This results into below crash as this memory
					  is now used by icq->__rcu_head in context#1.
					  There is a chance that icq could be free'd
					  as well.

22150.386550:   <6> Unable to handle kernel write to read-only memory
at virtual address ffffffaa8d31ca50
...
Call trace:
22150.607350:   <2>  ioc_destroy_icq+0x44/0x110
22150.611202:   <2>  ioc_clear_queue+0xac/0x148
22150.615056:   <2>  blk_cleanup_queue+0x11c/0x1a0
22150.619174:   <2>  __scsi_remove_device+0xdc/0x128
22150.623465:   <2>  scsi_forget_host+0x2c/0x78
22150.627315:   <2>  scsi_remove_host+0x7c/0x2a0
22150.631257:   <2>  usb_stor_disconnect+0x74/0xc8
22150.635371:   <2>  usb_unbind_interface+0xc8/0x278
22150.639665:   <2>  device_release_driver_internal+0x198/0x250
22150.644897:   <2>  device_release_driver+0x24/0x30
22150.649176:   <2>  bus_remove_device+0xec/0x140
22150.653204:   <2>  device_del+0x270/0x460
22150.656712:   <2>  usb_disable_device+0x120/0x390
22150.660918:   <2>  usb_disconnect+0xf4/0x2e0
22150.664684:   <2>  hub_event+0xd70/0x17e8
22150.668197:   <2>  process_one_work+0x210/0x480
22150.672222:   <2>  worker_thread+0x32c/0x4c8

Fix this by adding a new ICQ_DESTROYED flag in ioc_destroy_icq() to
indicate this icq is once marked as destroyed. Also, ensure
__ioc_clear_queue() is accessing icq within rcu_read_lock/unlock so
that icq doesn't get free'd up while it is still using it.
Signed-off-by: NSahitya Tummala <stummala@codeaurora.org>
Co-developed-by: NPradeep P V K <ppvk@codeaurora.org>
Signed-off-by: NPradeep P V K <ppvk@codeaurora.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This makes it possible to test the error path in blk_mq_realloc_hw_ctxs()
and also several error paths in null_blk.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If null_add_dev() fails then null_del_dev() is called with a NULL argument.
Make null_del_dev() handle this scenario correctly. This patch fixes the
following KASAN complaint:

null-ptr-deref in null_del_dev+0x28/0x280 [null_blk]
Read of size 8 at addr 0000000000000000 by task find/1062

Call Trace:
 dump_stack+0xa5/0xe6
 __kasan_report.cold+0x65/0x99
 kasan_report+0x16/0x20
 __asan_load8+0x58/0x90
 null_del_dev+0x28/0x280 [null_blk]
 nullb_group_drop_item+0x7e/0xa0 [null_blk]
 client_drop_item+0x53/0x80 [configfs]
 configfs_rmdir+0x395/0x4e0 [configfs]
 vfs_rmdir+0xb6/0x220
 do_rmdir+0x238/0x2c0
 __x64_sys_unlinkat+0x75/0x90
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If null_add_dev() fails, clear dev->nullb.

This patch fixes the following KASAN complaint:

BUG: KASAN: use-after-free in nullb_device_submit_queues_store+0xcf/0x160 [null_blk]
Read of size 8 at addr ffff88803280fc30 by task check/8409

Call Trace:
 dump_stack+0xa5/0xe6
 print_address_description.constprop.0+0x26/0x260
 __kasan_report.cold+0x7b/0x99
 kasan_report+0x16/0x20
 __asan_load8+0x58/0x90
 nullb_device_submit_queues_store+0xcf/0x160 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7ff370926317
Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007fff2dd2da48 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007ff370926317
RDX: 0000000000000002 RSI: 0000559437ef23f0 RDI: 0000000000000001
RBP: 0000559437ef23f0 R08: 000000000000000a R09: 0000000000000001
R10: 0000559436703471 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ff370a006a0 R14: 00007ff370a014a0 R15: 00007ff370a008a0

Allocated by task 8409:
 save_stack+0x23/0x90
 __kasan_kmalloc.constprop.0+0xcf/0xe0
 kasan_kmalloc+0xd/0x10
 kmem_cache_alloc_node_trace+0x129/0x4c0
 null_add_dev+0x24a/0xe90 [null_blk]
 nullb_device_power_store+0x1b6/0x270 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8409:
 save_stack+0x23/0x90
 __kasan_slab_free+0x112/0x160
 kasan_slab_free+0x12/0x20
 kfree+0xdf/0x250
 null_add_dev+0xaf3/0xe90 [null_blk]
 nullb_device_power_store+0x1b6/0x270 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: 2984c868 ("nullb: factor disk parameters")
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Instead of initializing null_blk hardware queues explicitly after the
request queue has been created, provide .init_hctx() and .exit_hctx()
callback functions. The latter functions are not only called during
request queue allocation but also when the number of hardware queues
changes. Allocate nr_cpu_ids queues during initialization to support
increasing the number of hardware queues above the initial hardware
queue count.

This change fixes increasing the number of hardware queues above the
initial number of hardware queues and also keeps nullb->nr_queues in
sync with the number of hardware queues.

Fixes: 45919fbf ("null_blk: Enable modifying 'submit_queues' after an instance has been configured")
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Although it is not clear to me why UBSAN complains when 'memory_backed'
is set, this patch suppresses the UBSAN complaint that is triggered when
setting that configfs attribute.

UBSAN: Undefined behaviour in drivers/block/null_blk_main.c:327:1
load of value 16 is not a valid value for type '_Bool'
CPU: 2 PID: 8396 Comm: check Not tainted 5.6.0-rc1-dbg+ #14
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
 dump_stack+0xa5/0xe6
 ubsan_epilogue+0x9/0x26
 __ubsan_handle_load_invalid_value+0x6d/0x76
 nullb_device_memory_backed_store.cold+0x2c/0x38 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

q->nr_hw_queues must only be updated once it is known that
blk_mq_realloc_hw_ctxs() has succeeded. Otherwise it can happen that
reallocation fails and that q->nr_hw_queues is larger than the number of
allocated hardware queues. This patch fixes the following crash if
increasing the number of hardware queues fails:

BUG: KASAN: null-ptr-deref in blk_mq_map_swqueue+0x775/0x810
Write of size 8 at addr 0000000000000118 by task check/977

CPU: 3 PID: 977 Comm: check Not tainted 5.6.0-rc1-dbg+ #8
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
 dump_stack+0xa5/0xe6
 __kasan_report.cold+0x65/0x99
 kasan_report+0x16/0x20
 check_memory_region+0x140/0x1b0
 memset+0x28/0x40
 blk_mq_map_swqueue+0x775/0x810
 blk_mq_update_nr_hw_queues+0x468/0x710
 nullb_device_submit_queues_store+0xf7/0x1a0 [null_blk]
 configfs_write_file+0x1c4/0x250 [configfs]
 __vfs_write+0x4c/0x90
 vfs_write+0x145/0x2c0
 ksys_write+0xd7/0x180
 __x64_sys_write+0x47/0x50
 do_syscall_64+0x6f/0x2f0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: ac0d6b92 ("block: Reduce the amount of memory required per request queue")
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

blk_mq_map_queues() and multiple .map_queues() implementations expect that
set->map[HCTX_TYPE_DEFAULT].nr_queues is set to the number of hardware
queues. Hence set .nr_queues before calling these functions. This patch
fixes the following kernel warning:

WARNING: CPU: 0 PID: 2501 at include/linux/cpumask.h:137
Call Trace:
 blk_mq_run_hw_queue+0x19d/0x350 block/blk-mq.c:1508
 blk_mq_run_hw_queues+0x112/0x1a0 block/blk-mq.c:1525
 blk_mq_requeue_work+0x502/0x780 block/blk-mq.c:775
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255

Fixes: ed76e329 ("blk-mq: abstract out queue map") # v5.0
Reported-by: syzbot+d44e1b26ce5c3e77458d@syzkaller.appspotmail.com
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>