put_all_bios() always drops devs[i].bio, but it only drops
devs[i].repl_bio when r10_bio->read_slot < 0. If discard reuses an
r10bio that was previously used for a read, read_slot can still be
non-negative, and discard cleanup can skip bio_put() on repl_bio.
Reset read_slot to -1 when preparing an r10bio for discard so the
replacement bio is always released correctly.
Fixes: d30588b273 ("md/raid10: improve raid10 discard request")
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Reviewed-by: Xiao Ni <xiao@kernel.org>
Link: https://patch.msgid.link/20260515093019.3436882-1-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
Calling update_raid_disks() with the same value as the current one
can trigger unnecessary work. For example, RAID1 will reallocate
resources such as the mempool for r1bio.
Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@gmail.com>
Link: https://patch.msgid.link/20260428130524.448063-1-abd.masalkhi@gmail.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
Returning DM_MAPIO_REQUEUE from the target map() function only requeues
the bio during noflush suspends. During regular operations or during
flushing suspends, it fails the bio. Failing the bio during flushing
suspends is the correct behavior here. The bio cannot be handled, and
dm-raid cannot suspend while it is outstanding. But during normal
operations, dm-raid should not push the bio back to dm. Instead, wait
for the reshape to be resumed.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Reviewed-by: Xiao Ni <xiao@kernel.org>
Link: https://patch.msgid.link/20260428232010.2785514-1-bmarzins@redhat.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
People have gone to the trouble of writing this kernel-doc; the
least we can do is publish it.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@linux.dev>
Link: https://patch.msgid.link/20260528175905.1102280-3-willy@infradead.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is a simple helper which replaces page_folio(bvec->bv_page).
Minor improvement in readability, but the real motivation is to reduce
the number of references to bvec->bv_page so that it can be changed
with less work.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@linux.dev>
Link: https://patch.msgid.link/20260528175905.1102280-2-willy@infradead.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A user can enable io accounting for passthrough requests, so export the
helper that checks if the request should be tracked. This will enable
stacking drivers to to report iostats for passthrough workloads. Since
the stacking request_queue may not be the one providing the request, the
API has to add a parameter for the caller to specify which one to check.
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260528010041.1533124-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a helper that sets bi_status and call bio_endio() as that is a very
common pattern and convert the core block code over to it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Md Haris Iqbal <haris.iqbal@linux.dev>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Link: https://patch.msgid.link/20260528084632.2505277-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The macros are impossible to follow due to the lack of visual type
information and all the braces. Replace them with inline helpers to
improve on that. Because the calling conventions are a bit problematic
with a lot of passing structures by value, all the helpers are marked
as __always_inline so that they are force inlined.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260527151043.2349900-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Split the two init cases based on code in the zloop driver. This
simplifies the code and makes it easier to follow.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260527151043.2349900-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Port over the changes from the zloop driver to remove the need for
the local bio, bvec and offset variables and clean up the code by
that.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260527151043.2349900-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
nvme_setup_descriptor_pools() indexes dev->descriptor_pools[] using the
numa_node forwarded from hctx->numa_node by its single caller,
nvme_init_hctx_common(). On a non-NUMA kernel hctx->numa_node is
NUMA_NO_NODE (-1). Because the parameter was declared 'unsigned', the
value becomes UINT_MAX and the index walks off the array (sized to
nr_node_ids), faulting during nvme_alloc_ns() and leaving the namespace
without a /dev node.
Reproduces on any NVMe controller probed by a CONFIG_NUMA=n kernel:
BUG: unable to handle page fault for address: ffff889101603d38
RIP: 0010:nvme_init_hctx_common+0x5a/0x190 [nvme]
Call Trace:
nvme_init_hctx+0x10/0x20 [nvme]
nvme_alloc_ns+0x9e/0xa10 [nvme_core]
nvme_scan_ns+0x301/0x3b0 [nvme_core]
nvme_scan_ns_async+0x23/0x30 [nvme_core]
Switch the parameter to int and fall back to node 0 when it is
NUMA_NO_NODE; node 0 is always present.
Fixes: d977506f88 ("nvme-pci: make PRP list DMA pools per-NUMA-node")
Link: https://lore.kernel.org/r/20260309062840.2937858-2-iam@sung-woo.kim
Reported-by: Sung-woo Kim <iam@sung-woo.kim>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mateusz Nowicki <mateusz.nowicki@posteo.net>
Signed-off-by: Keith Busch <kbusch@kernel.org>
nvmet_rdma_queue_connect() calls nvmet_rdma_find_get_device() which
acquires a reference on the returned ndev via kref_get(). On the path
where the host queue backlog is exceeded and the function returns
NVME_SC_CONNECT_CTRL_BUSY, reference of ndev is not released, leaking
the kref.
Fix this by adding a goto to the existing put_device label before the
early return.
Fixes: 31deaeb11b ("nvmet-rdma: avoid circular locking dependency on install_queue()")
Cc: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Signed-off-by: Keith Busch <kbusch@kernel.org>
struct nvme_ns_head contains a flexible array member, current_path[],
which is indexed using the NUMA node ID:
head->current_path[numa_node_id()]
The structure is currently allocated as:
size = sizeof(struct nvme_ns_head) +
(num_possible_nodes() * sizeof(struct nvme_ns *));
head = kzalloc(size, GFP_KERNEL);
This allocation assumes that NUMA node IDs are sequential and densely
packed from 0 .. num_possible_nodes() - 1. While this assumption holds
on many systems, it is not always true on some architectures such as
powerpc.
On some powerpc systems, NUMA node IDs can be sparse. For example:
NUMA:
NUMA node(s): 6
NUMA node0 CPU(s): 80-159
NUMA node8 CPU(s): 0-79
NUMA node252 CPU(s):
NUMA node253 CPU(s):
NUMA node254 CPU(s):
NUMA node255 CPU(s):
That is, the possible/online NUMA node IDs are: 0, 8, 252, 253, 254, 255
In this case: num_possible_nodes() = 6
So memory is allocated for only 6 entries in current_path[]. However,
the array is later indexed using the actual NUMA node ID. As a result,
accesses such as:
head->current_path[8] or
head->current_path[252]
goes out of bounds, leading to the following KASAN splat:
==================================================================
BUG: KASAN: slab-out-of-bounds in nvme_mpath_revalidate_paths+0x22c/0x290 [nvme_core]
Write of size 8 at addr c00020003bda35b8 by task kworker/u641:2/1997
CPU: 1 UID: 0 PID: 1997 Comm: kworker/u641:2 Not tainted 7.1.0-rc5-dirty #14 PREEMPT(lazy)
Hardware name: 8335-GTH POWER9 0x4e1202 opal:skiboot-v6.5.3-35-g1851b2a06 PowerNV
Workqueue: async async_run_entry_fn
Call Trace:
[c000200037fa7510] [c0000000021c23d4] dump_stack_lvl+0x88/0xdc (unreliable)
[c000200037fa7540] [c0000000009fda90] print_report+0x22c/0x67c
[c000200037fa7630] [c0000000009fd508] kasan_report+0x108/0x220
[c000200037fa7740] [c0000000009fff48] __asan_store8+0xe8/0x120
[c000200037fa7760] [c008000018e76474] nvme_mpath_revalidate_paths+0x22c/0x290 [nvme_core]
[c000200037fa7800] [c008000018e6556c] nvme_update_ns_info+0x4a4/0x5e0 [nvme_core]
[c000200037fa7a50] [c008000018e66270] nvme_alloc_ns+0x6d8/0x1a70 [nvme_core]
[c000200037fa7c20] [c008000018e679fc] nvme_scan_ns+0x3f4/0x630 [nvme_core]
[c000200037fa7d10] [c00000000031f22c] async_run_entry_fn+0x9c/0x3a0
[c000200037fa7db0] [c0000000002fa544] process_one_work+0x414/0xa10
[c000200037fa7ec0] [c0000000002fbf00] worker_thread+0x320/0x640
[c000200037fa7f80] [c00000000030d0f8] kthread+0x278/0x290
[c000200037fa7fe0] [c00000000000ded8] start_kernel_thread+0x14/0x18
Allocated by task 1997 on cpu 1 at 35.928317s:
The buggy address belongs to the object at c00020003bda3000
which belongs to the cache kmalloc-rnd-15-2k of size 2048
The buggy address is located 16 bytes to the right of
allocated 1448-byte region [c00020003bda3000, c00020003bda35a8)
The buggy address belongs to the physical page:
Memory state around the buggy address:
c00020003bda3480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
c00020003bda3500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>c00020003bda3580: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
^
c00020003bda3600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
c00020003bda3680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Fix this by allocating the flexible array using nr_node_ids instead
of num_possible_nodes(). Since nr_node_ids represents the maximum
possible NUMA node IDs, indexing current_path[] using numa_node_id()
becomes safe even on systems with sparse node IDs.
Fixes: f333444708 ("nvme: take node locality into account when selecting a path")
Tested-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
ublk_start_cancel() previously bailed out early when ublk_get_disk()
returned NULL, treating it as "our disk has been dead". That is correct
for the post-teardown case, but it also wrongly covers the pre-start
case: ublk_ctrl_start_dev() has not assigned ub->ub_disk yet, while
io_uring is already tearing down the daemon's uring_cmds via
ublk_uring_cmd_cancel_fn().
In that window, the cancel path skips ublk_set_canceling(), so
ubq->canceling stays false, even though ublk_cancel_cmd() goes on to
NULL out every io->cmd. ublk_ctrl_start_dev() then proceeds to set
ub->ub_disk, call add_disk(), and schedule partition_scan_work. When
ublk_partition_scan_work() runs bdev_disk_changed() and the resulting
read reaches ublk_queue_rq() -> ublk_queue_cmd(), the ubq->canceling
check passes and the code dereferences the NULL io->cmd:
BUG: kernel NULL pointer dereference, address: 0000000000000018
RIP: ublk_queue_cmd drivers/block/ublk_drv.c [inline]
RIP: ublk_queue_rq+0x73/0x100
Call Trace:
blk_mq_dispatch_rq_list+0x1c5/0xca0
...
bdev_disk_changed+0x3d4/0x5e0
ublk_partition_scan_work+0x89/0xe0
process_one_work+0x344/0x8a0
Fix it by always setting ub->canceling / ubq->canceling under
cancel_mutex. When the disk is allocated, keep the existing
quiesce/unquiesce dance so the flag is observed across the
ublk_queue_rq() barrier. When the disk is not yet allocated, there is
no request_queue and ublk_queue_rq() cannot be running concurrently, so
simply flipping the flag is sufficient: any subsequent I/O - including
the partition scan started by ublk_ctrl_start_dev() - will see
canceling set and be aborted via __ublk_queue_rq_common().
Fixes: 7fc4da6a30 ("ublk: scan partition in async way")
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Link: https://patch.msgid.link/20260527144042.2095194-1-tom.leiming@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE instead of
DEFINE_SYSFS_GROUP_VISIBLE, which means that we can drop
multipath_sysfs_attr_visible().
Incidentally, multipath_sysfs_attr_visible() should have returned a
umode_t.
This idea was suggested by Ben Marzinski elsewhere.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
The return value of nvmet_tcp_set_queue_sock() is currently ignored in
nvmet_tcp_tls_handshake_done(). If it fails (e.g., due to the socket
not being in TCP_ESTABLISHED state), the socket callbacks will not be
properly set, leading to queue and socket leakage.
Fix this by capturing the return value and calling
nvmet_tcp_schedule_release_queue() on failure to ensure proper cleanup.
Fixes: 675b453e02 ("nvmet-tcp: enable TLS handshake upcall")
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Signed-off-by: Keith Busch <kbusch@kernel.org>
tg_flush_bios() schedules pending_timer on the child tg's own
service_queue, which causes throtl_pending_timer_fn() to dispatch from
the child's pending_tree. For leaf cgroups this tree is empty, so the
timer fires and exits without dispatching the throttled bio.
The throttled bio sits in the parent's pending_tree with disptime set
to jiffies (THROTL_TG_CANCELING zeroes all dispatch times), but the
parent's timer is never explicitly rescheduled. The bio only gets
dispatched when the parent timer eventually fires at its previously
scheduled expiry.
Fix by calling throtl_schedule_next_dispatch(sq->parent_sq, true)
instead, matching what tg_set_limit() already does. This forces the
parent's dispatch cycle to run immediately and flush all canceling
bios without waiting for a stale timer.
For the device deletion path (blk_throtl_cancel_bios), directly
complete throttled bios with EIO via bio_io_error() instead of
dispatching them through the timer -> work -> submission chain.
This avoids a race with the SCSI state machine where bios can reach
the SCSI layer while the device is in SDEV_CANCEL state, causing
ENODEV instead of the expected EIO.
Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/all/ag2owaQQoigp_fSV@shinmob/
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Link: https://patch.msgid.link/20260522091530.1901437-1-cuitao@kylinos.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit b040a1a452 ("block: switch numa_node to int in
blk_mq_hw_ctx and init_request") changed the type of the
`numa_node` argument of `blk_mq_ops::init_request` from
`unsigned int` to `int`. Update the Rust callback signature to
match, so that the function item can be coerced to the C fn
pointer type stored in `blk_mq_ops`.
Without this change the Rust block layer fails to build:
error[E0308]: mismatched types
--> rust/kernel/block/mq/operations.rs:274:28
|
274 | init_request: Some(Self::init_request_callback),
| ---- ^^^^^^^^^^^^^^^^^^^^^^^^^^^
| expected fn pointer, found fn item
|
= note: expected fn pointer
`unsafe extern "C" fn(_, _, _, i32) -> _`
found fn item
`unsafe extern "C" fn(_, _, _, u32) -> _ {...}`
The argument is unused on the Rust side, so this is a pure
type-signature change with no functional impact.
Fixes: b040a1a452 ("block: switch numa_node to int in blk_mq_hw_ctx and init_request")
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260527-block-for-next-2026-05-26-2200-failure-v1-1-4865889e282c@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
check_partition() allocates a buffer to use as backing memory for
seq_buf.
This buffer can be allocated with kmalloc() as there's nothing special
about it to go directly to the page allocator.
kmalloc() provides a better API that does not require ugly casts and
kfree() does not need to know the size of the freed object.
For a single allocation on the cold path the performance difference between
kmalloc() and __get_free_pages() is not measurable as both allocators take
an object/page from a per-CPU list for fast path allocations.
For the slow path the performance is anyway determined by the amount of
reclaim involved rather than by what allocator is used.
Replace use of __get_free_page() with kmalloc() and free_page() with
kfree().
Link: https://lore.kernel.org/all/635405e4-9423-4a25-a6e7-e03c8ea0bcbe@redhat.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Link: https://patch.msgid.link/20260527-block-v2-1-8e06f914c484@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In nvmet_tcp_alloc_queue(), when a connection is closed during the
allocation process (e.g., nvmet_tcp_set_queue_sock() returns -ENOTCONN),
the error handling jumps to out_destroy_sq and then to out_ida_remove
without draining the page fragment cache.
Although nvmet_tcp_free_cmd() is called in some error paths to release
individual page fragments, the underlying page cache reference held by
queue->pf_cache is never released. The first allocation using pf_cache
is the call to nvmet_tcp_alloc_cmd() for queue->connect, which happens
after ida_alloc() returns successfully. This results in a page leak each
time a connection fails during allocation, which could lead to memory
exhaustion over time if connections are repeatedly opened and closed.
Fix this by calling page_frag_cache_drain() before freeing the queue
structure in the out_ida_remove label.
Fixes: 872d26a391 ("nvmet-tcp: add NVMe over TCP target driver")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Signed-off-by: Keith Busch <kbusch@kernel.org>
The timeout variable in nvme_wait_freeze_timeout() is an unsigned type.
Checking if it is <= 0 triggers a compiler warning because an unsigned
variable can never be negative.
Fix this warning by changing the type to long.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202605211257.STzj2Ujv-lkp@intel.com/
Fixes: 23b6d2cbf7 ("nvme: remove redundant timeout argument from nvme_wait_freeze_timeout")
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
NVMe multipath does not expose BLK_FEAT_PCI_P2PDMA on the head disk
even when all underlying controllers support it.
Set BLK_FEAT_PCI_P2PDMA unconditionally in nvme_mpath_alloc_disk()
alongside the other features. nvme_update_ns_info_block() already
calls queue_limits_stack_bdev() to stack each path's limits onto the
head disk, which routes through blk_stack_limits(). The core now
clears BLK_FEAT_PCI_P2PDMA automatically if any path (e.g., FC) does
not support it, consistent with how BLK_FEAT_NOWAIT and BLK_FEAT_POLL
are handled.
Tested-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Kiran Kumar Modukuri <kmodukuri@nvidia.com>
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Tested=by: Pranjal Shrivastava <praan@google.com>
Link: https://patch.msgid.link/20260513185153.95552-4-kch@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
MD RAID does not propagate BLK_FEAT_PCI_P2PDMA from member devices to
the RAID device, preventing peer-to-peer DMA through the RAID layer even
when all underlying devices support it.
Enable BLK_FEAT_PCI_P2PDMA unconditionally in raid0, raid1 and raid10
personalities during queue limits setup. blk_stack_limits() clears it
automatically if any member device lacks support, consistent with how
BLK_FEAT_NOWAIT and BLK_FEAT_POLL are handled in the block core.
Parity RAID personalities (raid4/5/6) are excluded because they require
CPU access to data pages for parity computation, which is incompatible
with P2P mappings.
Tested with RAID0/1/10 arrays containing multiple NVMe devices with
P2PDMA support, confirming that peer-to-peer transfers work correctly
through the RAID layer.
Tested-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Kiran Kumar Modukuri <kmodukuri@nvidia.com>
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Tested=by: Pranjal Shrivastava <praan@google.com>
Link: https://patch.msgid.link/20260513185153.95552-3-kch@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
BLK_FEAT_NOWAIT and BLK_FEAT_POLL are cleared in blk_stack_limits()
when an underlying device does not support them. Apply the same
treatment to BLK_FEAT_PCI_P2PDMA: stacking drivers set it
unconditionally and rely on the core to clear it whenever a
non-supporting member device is stacked.
Tested-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Tested=by: Pranjal Shrivastava <praan@google.com>
Link: https://patch.msgid.link/20260513185153.95552-2-kch@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Remove blkdev_write_begin(), blkdev_write_end(), and their entries in
def_blk_aops. These have been unreachable since commit 487c607df7
("block: use iomap for writes to block devices") switched block device
buffered writes from generic_perform_write() to
iomap_file_buffered_write(), which bypasses aops->write_begin/end.
Signed-off-by: Tal Zussman <tz2294@columbia.edu>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260525-blk-write-cleanup-v1-1-391c073e3831@columbia.edu
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If service thread creation fails after device_add_disk() succeeds,
mtip_block_initialize() calls del_gendisk() and then falls through to
put_disk(). Since mtip32xx uses .free_disk to free struct driver_data,
put_disk() can release dd on the added-disk path.
The same unwind then continues to use dd for blk_mq_free_tag_set() and
mtip_hw_exit(), and mtip_pci_probe() can later free dd again. This can
cause a use-after-free and double free.
Track whether the disk was added in the current initialization call.
For the post-add service-thread failure path, remove the disk, release
the local hardware resources, and return without dropping the final disk
reference. The probe error path can then finish its cleanup and call
put_disk() after it is done using dd. Keep the pre-add path using
put_disk() before blk_mq_free_tag_set(), and clear dd->disk so the outer
probe cleanup frees dd directly.
Fixes: e8b58ef09e ("mtip32xx: fix device removal")
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
Link: https://patch.msgid.link/20260525162531.1406677-1-dbgh9129@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit abb30460bd ("block: mark bio_wouldblock_error() bio with
BIO_QUIET") added this to suppress buffer_head warnings, but neither
when this commit was added nor now any buffer_head using code actually
ever sets REQ_NOWAIT which can lead to BLK_STS_AGAIN.
Remove the special handling for now. If we ever plan to use REQ_NOWAIT
for buffer_head based I/O we're better off handling BLK_STS_AGAIN in
the completion handler as it actually needs to retry the I/O as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260518063336.507369-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
None of the file systems using the legacy direct I/O code actually sets
FMODE_NOWAIT, and if they did this would not work, as the write locking
could not handle the retry. Remove this dead code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://patch.msgid.link/20260518063336.507369-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The bdev pseudo-filesystem is an internal kernel filesystem with which
userspace should not interfere. Unregister it so that userspace cannot
even attempt to mount it.
This fixes a bug [1] that occurs when attempting to access files,
because the system call move_mount() uses pointers declared in the
inode_operations structure, which for the bdev pseudo-filesystem
are always equal to 0. `inode->i_op = &empty_iops;`
[1]
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 23380067 P4D 23380067 PUD 23381067 PMD 0
Oops: 0010 [#1] PREEMPT SMP KASAN NOPTI
CPU: 2 PID: 17125 Comm: syz-executor.0 Not tainted 6.1.155-syzkaller-00350-g84221fde2681 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:0x0
Call Trace:
<TASK>
lookup_open.isra.0+0x700/0x1180 fs/namei.c:3460
open_last_lookups fs/namei.c:3550 [inline]
path_openat+0x953/0x2700 fs/namei.c:3780
do_filp_open+0x1c5/0x410 fs/namei.c:3810
do_sys_openat2+0x171/0x4d0 fs/open.c:1318
do_sys_open fs/open.c:1334 [inline]
__do_sys_openat fs/open.c:1350 [inline]
__se_sys_openat fs/open.c:1345 [inline]
__x64_sys_openat+0x13c/0x1f0 fs/open.c:1345
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x35/0x80 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Link: https://lore.kernel.org/all/20131010004732.GJ13318@ZenIV.linux.org.uk/T/#
Cc: stable@vger.kernel.org
Signed-off-by: Denis Arefev <arefev@swemel.ru>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260521072857.5078-1-arefev@swemel.ru
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bdev_mark_dead()'s @surprise == true means the device is already gone.
The filesystem callback fs_bdev_mark_dead() honours this and skips
sync_filesystem(), but the bare block device path (no ->mark_dead op)
lost its !surprise guard when the holder ->mark_dead callback was wired
up (see Fixes), and now calls sync_blockdev() unconditionally, which can
hang forever waiting on writeback that can no longer complete.
syzkaller hit this via nvme_reset_work()'s "I/O queues lost" path:
nvme_mark_namespaces_dead() -> blk_mark_disk_dead() ->
bdev_mark_dead(bdev, true) -> sync_blockdev() blocks in
folio_wait_writeback(), wedging the reset worker and every task waiting
on it.
Skip the sync on surprise removal, matching fs_bdev_mark_dead();
invalidate_bdev() still runs. Orderly removal (surprise == false) is
unchanged.
Found by FuzzNvme(Syzkaller with FEMU fuzzing framework).
Fixes: d8530de5a6 ("block: call into the file system for bdev_mark_dead")
Acked-by: Sungwoo Kim <iam@sung-woo.kim>
Acked-by: Dave Tian <daveti@purdue.edu>
Acked-by: Weidong Zhu <weizhu@fiu.edu>
Signed-off-by: Chao Shi <coshi036@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260522220025.1770388-1-coshi036@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In high-performance storage environments, particularly when utilising
RAID controllers with shared tag sets (BLK_MQ_F_TAG_HCTX_SHARED), severe
latency spikes can occur when fast devices (SSDs) are starved of hardware
tags when sharing the same blk_mq_tag_set.
Currently, diagnosing this specific hardware queue contention is
difficult. When a CPU thread exhausts the tag pool, blk_mq_get_tag()
forces the current thread to block uninterruptible via io_schedule().
While this can be inferred via sched:sched_switch or dynamically
traced by attaching a kprobe to blk_mq_mark_tag_wait(), there is no
dedicated, out-of-the-box observability for this event.
This patch introduces the block_rq_tag_wait tracepoint in the tag
allocation slow-path. It triggers immediately before the task state
is altered to TASK_UNINTERRUPTIBLE (ensuring safety for PREEMPT_RT
locks). It exposes the exact hardware context (hctx) that is starved,
the specific pool experiencing starvation (driver, software scheduler,
or reserved), and the exact pool depth.
This provides storage engineers with a zero-configuration, low-overhead
mechanism to definitively identify shared-tag bottlenecks. For example,
userspace can trivially replicate tag starvation counters using bpftrace:
# bpftrace -e 'tracepoint:block:block_rq_tag_wait { @tag_waits[cpu] = count(); }'
Attaching 1 probe...
^C
@tag_waits[4]: 12
@tag_waits[12]: 87
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Link: https://patch.msgid.link/20260525005123.722277-1-atomlin@atomlin.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
of_partition() calls of_node_get() on the parent device node at the
beginning of the function, storing the reference in 'partitions_np'.
This reference is leaked in two paths:
1. The compatibility check at the top of the function returns 0
without releasing partitions_np when the node exists but is not
"fixed-partitions" compatible.
2. The function returns 1 at the end after successfully processing
all partitions without releasing partitions_np.
Fix both leaks by adding of_node_put(partitions_np) on each path.
Fixes: 2e3a191e89 ("block: add support for partition table defined in OF")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Md Haris Iqbal <haris.iqbal@linux.dev>
Link: https://patch.msgid.link/20260526102124.2283846-1-vulab@iscas.ac.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The code for initializing struct ublksrv_io_desc on I/O dispatch is
largely duplicated in 3 places. Commit 4d4a512a1f ("ublk: add PFN-
based buffer matching in I/O path") added support to ublk_setup_iod()
for matching request buffers against registered UBLK_F_SHMEM_ZC buffers,
but missed adding it to ublk_setup_iod_zoned() for zoned requests. Move
the duplicated logic to a new helper ublk_init_iod(). This way, zone
appends can also benefit from avoiding the data copy.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Link: https://patch.msgid.link/20260520203654.1413640-3-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move ublk_req_build_flags() above its callers so it doesn't need to be
forward-declared.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Link: https://patch.msgid.link/20260520203654.1413640-2-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ublk_rq_has_data() currently uses bio_has_data(), which involves 2
indirections and several branches. Use blk_rq_has_data() instead to save
an indirection and NULL check.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Link: https://patch.msgid.link/20260513211846.1956810-3-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add blk_rq_has_data(), an analogue of bio_has_data() for struct request.
This skips one dereference relative to bio_has_data(rq->bio).
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Link: https://patch.msgid.link/20260513211846.1956810-2-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
nvme_update_ns_info_block() trusts id->lbaf[lbaf].ds from the
controller and assigns it directly to ns->head->lba_shift without
bounds checking. nvme_lba_to_sect() then does:
return lba << (head->lba_shift - SECTOR_SHIFT);
When called with lba = le64_to_cpu(id->nsze) to compute the device
capacity, an attacker-controlled controller can choose ds < 9 or a
combination of (ds, nsze) that makes the left shift overflow
sector_t. The former is a C undefined behaviour that UBSAN reports
as a BUG; the latter silently yields a bogus capacity that the
block layer then trusts for bounds checking.
Validate ds against SECTOR_SHIFT and use check_shl_overflow() to
compute capacity so that any (ds, nsze) combination that would
overflow sector_t is rejected. The namespace is skipped with
-ENODEV instead of crashing the kernel. This is reachable by a
malicious NVMe device, a buggy firmware, or an attacker-controlled
NVMe-oF target.
The check is performed before queue_limits_start_update() and
blk_mq_freeze_queue(), so the error path is a plain `goto out` with
no cleanup needed.
Stack trace (UBSAN, ds < 9 variant):
RIP: nvme_lba_to_sect drivers/nvme/host/nvme.h:699 [inline]
RIP: nvme_update_ns_info_block.cold+0x5/0x7
Call Trace:
nvme_update_ns_info+0x175/0xd90 drivers/nvme/host/core.c:2467
nvme_validate_ns drivers/nvme/host/core.c:4299 [inline]
nvme_scan_ns drivers/nvme/host/core.c:4350
nvme_scan_ns_async+0xa5/0xe0 drivers/nvme/host/core.c:4383
async_run_entry_fn
process_one_work
worker_thread
kthread
Found by Syzkaller.
Acked-by: Sungwoo Kim <iam@sung-woo.kim>
Acked-by: Dave Tian <daveti@purdue.edu>
Acked-by: Weidong Zhu <weizhu@fiu.edu>
Signed-off-by: Chao Shi <coshi036@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Currently, nvme_alloc_admin_tag_set() silently drops and releases
the existing admin_q if it called on a controller that already
had one (e.g., during a controller reset).
However, transport drivers should not be reallocating the admin tag
set and queue during a reset. Dropping the old queue and allocating
a new one destroys user-configured timeouts and may race against
nvme_admin_timeout_store()
Since all transport drivers are now expected to preserve the admin queue
across resets, calling nvme_alloc_admin_tag_set() when ctrl->admin_q
is already populated is a bug.
Remove the silent cleanup and replace it with a WARN_ON_ONCE() to
explicitly catch any transport drivers that violate this lifecycle rule
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Currently, resetting a loopback controller unconditionally invokes
nvme_alloc_admin_tag_set() inside nvme_loop_configure_admin_queue().
Doing so drops the old queue and allocates a new one. Consequently,
this reverts the admin queue's timeout (q->rq_timeout) back to the
module default (NVME_ADMIN_TIMEOUT), completely wiping out any custom
timeout values the user may have configured via sysfs and potentially
racing against the sysfs nvme_admin_timeout_store() function
that may dereference the admin_q pointer during the RESETTING state.
Decouple the admin tag set lifecycle from the admin queue
configuration and destruction paths, which are executed during resets;
Specifically:
* Move nvme_alloc_admin_tag_set() into nvme_loop_create_ctrl() so it
is only allocated once during the initial controller creation.
* Defer the destruction of the admin tag set to
nvme_loop_delete_ctrl_host() and the terminal error-handling
paths of nvme_loop_reset_ctrl_work() and
nvme_loop_create_ctrl().
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Currently, the final reference for the fabrics admin queue (fabrics_q)
is dropped inside nvme_remove_admin_tag_set(). However, the primary admin
queue (admin_q) defers dropping its final reference until
nvme_free_ctrl().
Move the blk_put_queue() call for fabrics_q from
nvme_remove_admin_tag_set() to nvme_free_ctrl(). This aligns the
lifecycle management of both admin queues, ensuring they are freed
symmetrically when the controller is finally torn down.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Currently, there is no method to adjust the timeout values on a
per controller basis with nvme I/O queues.
Add an io_timeout attribute to nvme so that different nvme controllers
which may have different timeout requirements can have custom I/O
timeouts set.
The I/O timeout is also applied to the connect queue (connect_q).
In NVMe over Fabrics, the connect queue is utilized specifically to
issue Connect commands that establish the I/O queues.
Reviewed-by: Mohamed Khalfella <mkhalfella@purestorage.com>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Currently, there is no method to adjust the timeout values on a
per-controller basis with nvme admin queues.
Add an admin_timeout attribute to nvme so that different nvme controllers
which may have different timeout requirements can have custom admin
timeouts set.
The admin timeout is also applied to the fabrics queue (fabrics_q).
The fabrics queue is utilized for fabric-specific administrative and
control operations, such as Connect and Property Get/Set commands.
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Mohamed Khalfella <mkhalfella@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
All callers of nvme_wait_freeze_timeout() currently pass the exact same
NVME_IO_TIMEOUT default as their timeout argument.
Remove it and use a local variable.
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Mohamed Khalfella <mkhalfella@purestorage.com>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
When initializing an nvme request which is about to be send to the block
layer, we do not need to initialize its timeout. If it's left
uninitialized at 0 the block layer will use the request queue's timeout
in blk_add_timer (via nvme_start_request which is called from
nvme_*_queue_rq). These timeouts are setup to either NVME_IO_TIMEOUT or
NVME_ADMIN_TIMEOUT when the request queues were created.
Because the io_timeout of the IO queues can be modified via sysfs, the
following situation can occur:
1) NVME_IO_TIMEOUT = 30 (default module parameter)
2) nvme1n1 is probed. IO queues default timeout is 30 s
3) manually change the IO timeout to 90 s
echo 90000 > /sys/class/nvme/nvme1/nvme1n1/queue/io_timeout
4) Any call of __submit_sync_cmd on nvme1n1 to an IO queue will issue
commands with the 30 s timeout instead of the wanted 90 s which might
be more suitable for this device.
Commit 470e900c80 ("nvme: refactor nvme_alloc_request") silently
changed the behavior for ioctl's already because it unconditionally
overrides the request's timeout that was set in nvme_init_request. If it
was unset by the user of the ioctl if will be overridden with 0 meaning
the block layer will pick the request queue's IO timeout.
Following up on that, this patch further improves the consistency of IO
timeout usage. However, there are still uses of NVME_IO_TIMEOUT which
could be inconsistent with what is set in the device's request_queue by
the user.
Reviewed-by: Mohamed Khalfella <mkhalfella@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Signed-off-by: Maximilian Heyne <mheyne@amazon.de>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>