linux.git/block, branch v4.12-rc4

block: Avoid that blk_exit_rl() triggers a use-after-free

2017-06-01T19:07:55+00:00

Since the introduction of .init_rq_fn() and .exit_rq_fn() it is
essential that the memory allocated for struct request_queue
stays around until all blk_exit_rl() calls have finished. Hence
make blk_init_rl() take a reference on struct request_queue.

This patch fixes the following crash:

general protection fault: 0000 [#2] SMP
CPU: 3 PID: 28 Comm: ksoftirqd/3 Tainted: G      D         4.12.0-rc2-dbg+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
task: ffff88013a108040 task.stack: ffffc9000071c000
RIP: 0010:free_request_size+0x1a/0x30
RSP: 0018:ffffc9000071fd38 EFLAGS: 00010202
RAX: 6b6b6b6b6b6b6b6b RBX: ffff880067362a88 RCX: 0000000000000003
RDX: ffff880067464178 RSI: ffff880067362a88 RDI: ffff880135ea4418
RBP: ffffc9000071fd40 R08: 0000000000000000 R09: 0000000100180009
R10: ffffc9000071fd38 R11: ffffffff81110800 R12: ffff88006752d3d8
R13: ffff88006752d3d8 R14: ffff88013a108040 R15: 000000000000000a
FS:  0000000000000000(0000) GS:ffff88013fd80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa8ec1edb00 CR3: 0000000138ee8000 CR4: 00000000001406e0
Call Trace:
 mempool_destroy.part.10+0x21/0x40
 mempool_destroy+0xe/0x10
 blk_exit_rl+0x12/0x20
 blkg_free+0x4d/0xa0
 __blkg_release_rcu+0x59/0x170
 rcu_process_callbacks+0x260/0x4e0
 __do_softirq+0x116/0x250
 smpboot_thread_fn+0x123/0x1e0
 kthread+0x109/0x140
 ret_from_fork+0x31/0x40

Fixes: commit e9c787e65c0c ("scsi: allocate scsi_cmnd structures as part of struct request")
Signed-off-by: Bart Van Assche 
Acked-by: Tejun Heo 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Christoph Hellwig 
Cc: Jan Kara 
Cc:  # v4.11+
Signed-off-by: Jens Axboe

cfq-iosched: fix the delay of cfq_group's vdisktime under iops mode

2017-05-31T15:25:21+00:00

When adding a cfq_group into the cfq service tree, we use CFQ_IDLE_DELAY
as the delay of cfq_group's vdisktime if there have been other cfq_groups
already.

When cfq is under iops mode, commit 9a7f38c42c2b ("cfq-iosched: Convert
from jiffies to nanoseconds") could result in a large iops delay and
lead to an abnormal io schedule delay for the added cfq_group. To fix
it, we just need to revert to the old CFQ_IDLE_DELAY value: HZ / 5
when iops mode is enabled.

Despite having the same value, the delay of a cfq_queue in idle class
and the delay of cfq_group are different things, so I define two new
macros for the delay of a cfq_group under time-slice mode and iops mode.

Fixes: 9a7f38c42c2b ("cfq-iosched: Convert from jiffies to nanoseconds")
Cc:  # 4.8+
Signed-off-by: Hou Tao 
Acked-by: Jan Kara 
Signed-off-by: Jens Axboe

blk-mq: Take tagset lock when updating hw queues

2017-05-30T18:32:37+00:00

The tagset lock needs to be held when iterating the tag_list, so a
lockdep assert was added when updating number of hardware queues. The
drivers calling this API, however, were unaware of the new requirement,
so are failing the assertion.

This patch takes the lock within the blk-mq function so the drivers do
not have to be modified in order to be safe.

Fixes: 705cda97e ("blk-mq: Make it safe to use RCU to iterate over blk_mq_tag_set.tag_list")
Reported-by: Gabriel Krisman Bertazi 
Reviewed-by: Bart Van Assche 
Signed-off-by: Keith Busch 
Signed-off-by: Jens Axboe

Merge branch 'nvme-4.12' of git://git.infradead.org/nvme into for-linus

2017-05-26T15:11:19+00:00

Christoph writes:

"A couple of fixes for the next rc on the nvme front. Various FC fixes
from James, controller removal fixes from Ming (including a block layer
patch), a APST related device quirk from Andy, a RDMA fix for small
queue depth device from Marta, as well as fixes for the lack of
metadata support in non-PCIe drivers and the printk logging format from
me."

blk-mq: Only register debugfs attributes for blk-mq queues

2017-05-26T13:25:13+00:00

The code in blk-mq-debugfs.c assumes that it is working on a blk-mq
queue and is not intended to work on a blk-sq queue. Hence only
register blk-mq debugfs attributes for blk-mq queues.

Fixes: commit 9c1051aacde8 ("blk-mq: untangle debugfs and sysfs")
Signed-off-by: Bart Van Assche 
Cc: Christoph Hellwig 
Cc: Ming Lei 
Reviewed-by: Omar Sandoval 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jens Axboe

partitions/msdos: FreeBSD UFS2 file systems are not recognized

2017-05-23T15:16:07+00:00

The code in block/partitions/msdos.c recognizes FreeBSD, OpenBSD
and NetBSD partitions and does a reasonable job picking out OpenBSD
and NetBSD UFS subpartitions.

But for FreeBSD the subpartitions are always "bad".

    Kernel: 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

block: fix an error code in add_partition()

2017-05-23T14:41:59+00:00

We don't set an error code on this path.  It means that we return NULL
instead of an error pointer and the caller does a NULL dereference.

Fixes: 6d1d8050b4bc ("block, partition: add partition_meta_info to hd_struct")
Signed-off-by: Dan Carpenter 
Signed-off-by: Jens Axboe

blk-throttle: force user to configure all settings for io.low

2017-05-22T20:47:12+00:00

Default value of io.low limit is 0. If user doesn't configure the limit,
last patch makes cgroup be throttled to very tiny bps/iops, which could
stall the system. A cgroup with default settings of io.low limit really
means nothing, so we force user to configure all settings, otherwise
io.low limit doesn't take effect. With this stragety, default setting of
latency/idle isn't important, so just set them to very conservative and
safe value.

Signed-off-by: Shaohua Li 
Acked-by: Tejun Heo 
Signed-off-by: Jens Axboe

blk-throttle: respect 0 bps/iops settings for io.low

2017-05-22T20:47:12+00:00

If a cgroup with low limit 0 for both bps/iops, the cgroup's low limit
is ignored and we throttle the cgroup with its max limit. In this way,
other cgroups with a low limit will not get protected. To fix this, we
don't do the exception any more. cgroup will be throttled to a limit 0
if it uese default setting. To avoid completed stall, we give such
cgroup tiny IO resources.

Signed-off-by: Shaohua Li 
Acked-by: Tejun Heo 
Signed-off-by: Jens Axboe

blk-throttle: output some debug info in trace

2017-05-22T20:47:12+00:00

These info are important to understand what's happening and help debug.

Signed-off-by: Shaohua Li 
Acked-by: Tejun Heo 
Signed-off-by: Jens Axboe