user/sven/linux.git/block, branch v6.16.1

block: ensure discard_granularity is zero when discard is not supported

2025-08-15T14:39:24Z

[ Upstream commit fad6551fcf537375702b9af012508156a16a1ff7 ] Documentation/ABI/stable/sysfs-block states: What: /sys/block//queue/discard_granularity [...] A discard_granularity of 0 means that the device does not support discard functionality. but this got broken when sorting out the block limits updates. Fix this by setting the discard_granularity limit to zero when the combined max_discard_sectors is zero. Fixes: 3c407dc723bb ("block: default the discard granularity to sector size") Signed-off-by: Christoph Hellwig Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20250731152228.873923-1-hch@lst.de Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: restore two stage elevator switch while running nr_hw_queue update

2025-08-15T14:38:24Z

[ Upstream commit 5989bfe6ac6bf230c2c84e118c786be0ed4be3f4 ] The kmemleak reports memory leaks related to elevator resources that were originally allocated in the ->init_hctx() method. The following leak traces are observed after running blktests block/040: unreferenced object 0xffff8881b82f7400 (size 512): comm "check", pid 68454, jiffies 4310588881 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 5bac8b34): __kvmalloc_node_noprof+0x55d/0x7a0 sbitmap_init_node+0x15a/0x6a0 kyber_init_hctx+0x316/0xb90 blk_mq_init_sched+0x419/0x580 elevator_switch+0x18b/0x630 elv_update_nr_hw_queues+0x219/0x2c0 __blk_mq_update_nr_hw_queues+0x36a/0x6f0 blk_mq_update_nr_hw_queues+0x3a/0x60 0xffffffffc09ceb80 0xffffffffc09d7e0b configfs_write_iter+0x2b1/0x470 vfs_write+0x527/0xe70 ksys_write+0xff/0x200 do_syscall_64+0x98/0x3c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e unreferenced object 0xffff8881b82f6000 (size 512): comm "check", pid 68454, jiffies 4310588881 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 5bac8b34): __kvmalloc_node_noprof+0x55d/0x7a0 sbitmap_init_node+0x15a/0x6a0 kyber_init_hctx+0x316/0xb90 blk_mq_init_sched+0x419/0x580 elevator_switch+0x18b/0x630 elv_update_nr_hw_queues+0x219/0x2c0 __blk_mq_update_nr_hw_queues+0x36a/0x6f0 blk_mq_update_nr_hw_queues+0x3a/0x60 0xffffffffc09ceb80 0xffffffffc09d7e0b configfs_write_iter+0x2b1/0x470 vfs_write+0x527/0xe70 ksys_write+0xff/0x200 do_syscall_64+0x98/0x3c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e unreferenced object 0xffff8881b82f5800 (size 512): comm "check", pid 68454, jiffies 4310588881 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 5bac8b34): __kvmalloc_node_noprof+0x55d/0x7a0 sbitmap_init_node+0x15a/0x6a0 kyber_init_hctx+0x316/0xb90 blk_mq_init_sched+0x419/0x580 elevator_switch+0x18b/0x630 elv_update_nr_hw_queues+0x219/0x2c0 __blk_mq_update_nr_hw_queues+0x36a/0x6f0 blk_mq_update_nr_hw_queues+0x3a/0x60 0xffffffffc09ceb80 0xffffffffc09d7e0b configfs_write_iter+0x2b1/0x470 vfs_write+0x527/0xe70 ksys_write+0xff/0x200 do_syscall_64+0x98/0x3c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The issue arises while we run nr_hw_queue update, Specifically, we first reallocate hardware contexts (hctx) via __blk_mq_realloc_hw_ctxs(), and then later invoke elevator_switch() (assuming q->elevator is not NULL). The elevator switch code would first exit old elevator (elevator_exit) and then switches to the new elevator. The elevator_exit loops through each hctx and invokes the elevator’s per-hctx exit method ->exit_hctx(), which releases resources allocated during ->init_hctx(). This memleak manifests when we reduce the num of h/w queues - for example, when the initial update sets the number of queues to X, and a later update reduces it to Y, where Y < X. In this case, we'd loose the access to old hctxs while we get to elevator exit code because __blk_mq_realloc_hw_ctxs would have already released the old hctxs. As we don't now have any reference left to the old hctxs, we don't have any way to free the scheduler resources (which are allocate in ->init_hctx()) and kmemleak complains about it. This issue was caused due to the commit 596dce110b7d ("block: simplify elevator reattachment for updating nr_hw_queues"). That change unified the two-stage elevator teardown and reattachment into a single call that occurs after __blk_mq_realloc_hw_ctxs() has already freed the hctxs. This patch restores the previous two-stage elevator switch logic during nr_hw_queues updates. First, the elevator is switched to 'none', which ensures all scheduler resources are properly freed. Then, the hardware contexts (hctxs) are reallocated, and the software-to-hardware queue mappings are updated. Finally, the original elevator is reattached. This sequence prevents loss of references to old hctxs and avoids the scheduler resource leaks reported by kmemleak. Reported-by : Yi Zhang Fixes: 596dce110b7d ("block: simplify elevator reattachment for updating nr_hw_queues") Closes: https://lore.kernel.org/all/CAHj4cs8oJFvz=daCvjHM5dYCNQH4UXwSySPPU4v-WHce_kZXZA@mail.gmail.com/ Signed-off-by: Nilay Shroff Reviewed-by: Yu Kuai Link: https://lore.kernel.org/r/20250724102540.1366308-1-nilay@linux.ibm.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: sanitize chunk_sectors for atomic write limits

2025-08-15T14:38:23Z

[ Upstream commit 1de67e8e28fc47d71ee06ffa0185da549b378ffb ] Currently we just ensure that a non-zero value in chunk_sectors aligns with any atomic write boundary, as the blk boundary functionality uses both these values. However it is also improper to have atomic write unit max > chunk_sectors (for non-zero chunk_sectors), as this would lead to splitting of atomic write bios (which is disallowed). Sanitize atomic write unit max against chunk_sectors to avoid any potential problems. Fixes: d00eea91deaf3 ("block: Add extra checks in blk_validate_atomic_write_limits()") Reviewed-by: Nilay Shroff Signed-off-by: John Garry Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20250711105258.3135198-3-john.g.garry@oracle.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

Merge tag 'block-6.16-20250725' of git://git.kernel.dk/linux

2025-07-25T15:05:17Z

Pull block fix from Jens Axboe: "Just a single fix for regression in this release, where a module reference could be leaked" * tag 'block-6.16-20250725' of git://git.kernel.dk/linux: block: fix module reference leak in mq-deadline I/O scheduler

block: fix module reference leak in mq-deadline I/O scheduler

2025-07-20T19:18:13Z

During probe, when the block layer registers a request queue, it defaults to the mq-deadline I/O scheduler if the device is single-queue and the mq-deadline module is available. To determine availability, the elevator_set_default() invokes elevator_find_get(), which increments the module's reference count. However, this reference is never released, resulting in a module reference leak that prevents the mq-deadline module from being unloaded. This patch fixes the issue by ensuring the acquired module reference is properly released. Fixes: 1e44bedbc921 ("block: unifying elevator change") Signed-off-by: Nilay Shroff Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20250719132722.769536-1-nilay@linux.ibm.com Signed-off-by: Jens Axboe

Merge tag 'block-6.16-20250718' of git://git.kernel.dk/linux

2025-07-18T19:16:13Z

Pull block fixes from Jens Axboe: - NVMe changes via Christoph: - revert the cross-controller atomic write size validation that caused regressions (Christoph Hellwig) - fix endianness of command word printout in nvme_log_err_passthru() (John Garry) - fix callback lock for TLS handshake (Maurizio Lombardi) - fix misaccounting of nvme-mpath inflight I/O (Yu Kuai) - fix inconsistent RCU list manipulation in nvme_ns_add_to_ctrl_list() (Zheng Qixing) - Fix for a kobject leak in queue unregistration - Fix for loop async file write start/end handling * tag 'block-6.16-20250718' of git://git.kernel.dk/linux: loop: use kiocb helpers to fix lockdep warning nvmet-tcp: fix callback lock for TLS handshake nvme: fix misaccounting of nvme-mpath inflight I/O nvme: revert the cross-controller atomic write size validation nvme: fix endianness of command word prints in nvme_log_err_passthru() nvme: fix inconsistent RCU list manipulation in nvme_ns_add_to_ctrl_list() block: fix kobject leak in blk_unregister_queue

block: fix kobject leak in blk_unregister_queue

2025-07-12T02:39:23Z

The kobject for the queue, `disk->queue_kobj`, is initialized with a reference count of 1 via `kobject_init()` in `blk_register_queue()`. While `kobject_del()` is called during the unregister path to remove the kobject from sysfs, the initial reference is never released. Add a call to `kobject_put()` in `blk_unregister_queue()` to properly decrement the reference count and fix the leak. Fixes: 2bd85221a625 ("block: untangle request_queue refcounting from sysfs") Cc: Christoph Hellwig Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20250711083009.2574432-1-ming.lei@redhat.com Signed-off-by: Jens Axboe

Merge tag 'block-6.16-20250626' of git://git.kernel.dk/linux

2025-06-27T16:02:33Z

Pull block fixes from Jens Axboe: - Fixes for ublk: - fix C++ narrowing warnings in the uapi header - update/improve UBLK_F_SUPPORT_ZERO_COPY comment in uapi header - fix for the ublk ->queue_rqs() implementation, limiting a batch to just the specific task AND ring - ublk_get_data() error handling fix - sanity check more arguments in ublk_ctrl_add_dev() - selftest addition - NVMe pull request via Christoph: - reset delayed remove_work after reconnect - fix atomic write size validation - Fix for a warning introduced in bdev_count_inflight_rw() in this merge window * tag 'block-6.16-20250626' of git://git.kernel.dk/linux: block: fix false warning in bdev_count_inflight_rw() ublk: sanity check add_dev input for underflow nvme: fix atomic write size validation nvme: refactor the atomic write unit detection nvme: reset delayed remove_work after reconnect ublk: setup ublk_io correctly in case of ublk_get_data() failure ublk: update UBLK_F_SUPPORT_ZERO_COPY comment in UAPI header ublk: fix narrowing warnings in UAPI header selftests: ublk: don't take same backing file for more than one ublk devices ublk: build batch from IOs in same io_ring_ctx and io task

block: fix false warning in bdev_count_inflight_rw()

2025-06-26T13:34:11Z

While bdev_count_inflight is interating all cpus, if some IOs are issued from traversed cpu and then completed from the cpu that is not traversed yet: cpu0 cpu1 bdev_count_inflight //for_each_possible_cpu // cpu0 is 0 infliht += 0 // issue a io blk_account_io_start // cpu0 inflight ++ cpu2 // the io is done blk_account_io_done // cpu2 inflight -- // cpu 1 is 0 inflight += 0 // cpu2 is -1 inflight += -1 ... In this case, the total inflight will be -1, causing lots of false warning. Fix the problem by removing the warning. Noted there is still a valid warning for nvme-mpath(From Yi) that is not fixed yet. Fixes: f5482ee5edb9 ("block: WARN if bdev inflight counter is negative") Reported-by: Yi Zhang Closes: https://lore.kernel.org/linux-block/aFtUXy-lct0WxY2w@mozart.vkv.me/T/#mae89155a5006463d0a21a4a2c35ae0034b26a339 Reported-and-tested-by: Calvin Owens Closes: https://lore.kernel.org/linux-block/aFtUXy-lct0WxY2w@mozart.vkv.me/T/#m1d935a00070bf95055d0ac84e6075158b08acaef Reported-by: Dave Chinner Closes: https://lore.kernel.org/linux-block/aFuypjqCXo9-5_En@dread.disaster.area/ Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20250626115743.1641443-1-yukuai3@huawei.com Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe

Merge tag 'block-6.16-20250614' of git://git.kernel.dk/linux

2025-06-14T16:25:22Z

Pull block fixes from Jens Axboe: - Fix for a deadlock on queue freeze with zoned writes - Fix for zoned append emulation - Two bio folio fixes, for sparsemem and for very large folios - Fix for a performance regression introduced in 6.13 when plug insertion was changed - Fix for NVMe passthrough handling for polled IO - Document the ublk auto registration feature - loop lockdep warning fix * tag 'block-6.16-20250614' of git://git.kernel.dk/linux: nvme: always punt polled uring_cmd end_io work to task_work Documentation: ublk: Separate UBLK_F_AUTO_BUF_REG fallback behavior sublists block: Fix bvec_set_folio() for very large folios bio: Fix bio_first_folio() for SPARSEMEM without VMEMMAP block: use plug request list tail for one-shot backmerge attempt block: don't use submit_bio_noacct_nocheck in blk_zone_wplug_bio_work block: Clear BIO_EMULATES_ZONE_APPEND flag on BIO completion ublk: document auto buffer registration(UBLK_F_AUTO_BUF_REG) loop: move lo_set_size() out of queue freeze