kernel/linux.git/drivers/nvdimm, branch v6.12.101

nvdimm/btt: Free arena sub-allocations on discover_arenas() error path

2026-07-24T14:11:31+00:00

commit 13fe4cd9ddd0aacb7777812328be525a11ea3fea upstream. Memory allocated by btt_freelist_init(), btt_rtt_init(), and btt_maplocks_init() is not freed on some discover_arenas() error paths. This leaks memory when arena discovery fails. Add the missing kfree() calls to release the allocations before returning an error. [ as: commit message and log edits ] Fixes: 5212e11fde4d ("nd_btt: atomic sector updates") Cc: stable@vger.kernel.org Signed-off-by: Abdun Nihaal Reviewed-by: Alison Schofield Link: https://patch.msgid.link/20260519-nvdimmleaks-v1-1-592300fb7a43@cse.iitm.ac.in Signed-off-by: Alison Schofield Signed-off-by: Greg Kroah-Hartman

nvdimm/btt: Free arenas on btt_init() error paths

2026-07-24T14:11:31+00:00

commit 1a6b6442a982d0ca5fb6a1a39b6f6dfd760eda57 upstream. The arenas allocated by discover_arenas() or create_arenas() are not freed on some error paths in btt_init(). This leaks memory when BTT initialization fails. Call free_arenas() from the affected error paths to release the allocations. [ as: commit message and log edits ] Fixes: 5212e11fde4d ("nd_btt: atomic sector updates") Cc: stable@vger.kernel.org Signed-off-by: Abdun Nihaal Reviewed-by: Alison Schofield Link: https://patch.msgid.link/20260519-nvdimmleaks-v1-2-592300fb7a43@cse.iitm.ac.in Signed-off-by: Alison Schofield Signed-off-by: Greg Kroah-Hartman

nvdimm/btt: Handle preemption in BTT lane acquisition

2026-07-24T14:10:53+00:00

[ Upstream commit 8d4b989d9c9afe5f185aa5853b666fc4617afe9e ] BTT lanes serialize access to per-lane metadata and workspace state during BTT I/O. The btt-check unit test reports data mismatches during BTT writes due to a race in lane acquisition that can lead to silent data corruption. The existing lane model uses a spinlock together with a per-CPU recursion count. That recursion model stopped being valid after BTT lanes became preemptible: another task can run on the same CPU, observe a non-zero recursion count, bypass locking, and use the same lane concurrently. BTT lanes are also held across arena_write_bytes() calls. That path reaches nsio_rw_bytes(), which flushes writes with nvdimm_flush(). Some provider flush callbacks can sleep, making a spinlock the wrong primitive for the lane lifetime. Replace the spinlock-based recursion model with a dynamically allocated per-lane mutex array and take the lane lock unconditionally. Add might_sleep() to catch any future atomic-context caller. Found with the ndctl unit test btt-check.sh. Fixes: 36c75ce3bd29 ("nd_btt: Make BTT lanes preemptible") Assisted-by: Claude-Sonnet:4.5 Tested-by: Aboorva Devarajan Reviewed-by: Aboorva Devarajan Reviewed-by: Vishal Verma Reviewed-by: Dave Jiang Link: https://patch.msgid.link/20260528021625.618462-1-alison.schofield@intel.com Signed-off-by: Alison Schofield Signed-off-by: Sasha Levin

nvdimm/bus: Fix potential use after free in asynchronous initialization

2026-03-25T10:08:47+00:00

commit a8aec14230322ed8f1e8042b6d656c1631d41163 upstream. Dingisoul with KASAN reports a use after free if device_add() fails in nd_async_device_register(). Commit b6eae0f61db2 ("libnvdimm: Hold reference on parent while scheduling async init") correctly added a reference on the parent device to be held until asynchronous initialization was complete. However, if device_add() results in an allocation failure the ref count of the device drops to 0 prior to the parent pointer being accessed. Thus resulting in use after free. The bug bot AI correctly identified the fix. Save a reference to the parent pointer to be used to drop the parent reference regardless of the outcome of device_add(). Reported-by: Dingisoul Closes: http://lore.kernel.org/8855544b-be9e-4153-aa55-0bc328b13733@gmail.com Fixes: b6eae0f61db2 ("libnvdimm: Hold reference on parent while scheduling async init") Cc: stable@vger.kernel.org Reviewed-by: Dave Jiang Link: https://patch.msgid.link/20260306-fix-uaf-async-init-v1-1-a28fd7526723@intel.com Signed-off-by: Ira Weiny Signed-off-by: Greg Kroah-Hartman

nvdimm: virtio_pmem: serialize flush requests

2026-03-04T12:20:24+00:00

[ Upstream commit a9ba6733c7f1096c4506bf4e34a546e07242df74 ] Under heavy concurrent flush traffic, virtio-pmem can overflow its request virtqueue (req_vq): virtqueue_add_sgs() starts returning -ENOSPC and the driver logs "no free slots in the virtqueue". Shortly after that the device enters VIRTIO_CONFIG_S_NEEDS_RESET and flush requests fail with "virtio pmem device needs a reset". Serialize virtio_pmem_flush() with a per-device mutex so only one flush request is in-flight at a time. This prevents req_vq descriptor overflow under high concurrency. Reproducer (guest with virtio-pmem): - mkfs.ext4 -F /dev/pmem0 - mount -t ext4 -o dax,noatime /dev/pmem0 /mnt/bench - fio: ioengine=io_uring rw=randwrite bs=4k iodepth=64 numjobs=64 direct=1 fsync=1 runtime=30s time_based=1 - dmesg: "no free slots in the virtqueue" "virtio pmem device needs a reset" Fixes: 6e84200c0a29 ("virtio-pmem: Add virtio pmem driver") Signed-off-by: Li Chen Acked-by: Pankaj Gupta Acked-by: Michael S. Tsirkin Link: https://patch.msgid.link/20260203021353.121091-1-me@linux.beauty Signed-off-by: Ira Weiny Signed-off-by: Sasha Levin

libnvdimm/labels: Fix divide error in nd_label_data_init()

2025-05-29T09:02:09+00:00

[ Upstream commit ef1d3455bbc1922f94a91ed58d3d7db440652959 ] If a faulty CXL memory device returns a broken zero LSA size in its memory device information (Identify Memory Device (Opcode 4000h), CXL spec. 3.1, 8.2.9.9.1.1), a divide error occurs in the libnvdimm driver: Oops: divide error: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:nd_label_data_init+0x10e/0x800 [libnvdimm] Code and flow: 1) CXL Command 4000h returns LSA size = 0 2) config_size is assigned to zero LSA size (CXL pmem driver): drivers/cxl/pmem.c: .config_size = mds->lsa_size, 3) max_xfer is set to zero (nvdimm driver): drivers/nvdimm/label.c: max_xfer = min_t(size_t, ndd->nsarea.max_xfer, config_size); 4) A subsequent DIV_ROUND_UP() causes a division by zero: drivers/nvdimm/label.c: /* Make our initial read size a multiple of max_xfer size */ drivers/nvdimm/label.c: read_size = min(DIV_ROUND_UP(read_size, max_xfer) * max_xfer, drivers/nvdimm/label.c- config_size); Fix this by checking the config size parameter by extending an existing check. Signed-off-by: Robert Richter Reviewed-by: Pankaj Gupta Reviewed-by: Ira Weiny Link: https://patch.msgid.link/20250320112223.608320-1-rrichter@amd.com Signed-off-by: Ira Weiny Signed-off-by: Sasha Levin

nvdimm: rectify the illogical code within nd_dax_probe()

2024-12-14T19:04:02+00:00

[ Upstream commit b61352101470f8b68c98af674e187cfaa7c43504 ] When nd_dax is NULL, nd_pfn is consequently NULL as well. Nevertheless, it is inadvisable to perform pointer arithmetic or address-taking on a NULL pointer. Introduce the nd_dax_devinit() function to enhance the code's logic and improve its readability. Signed-off-by: Yi Yang Reviewed-by: Dave Jiang Link: https://patch.msgid.link/20241108085526.527957-1-yiyang13@huawei.com Signed-off-by: Ira Weiny Signed-off-by: Sasha Levin

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2024-09-26T15:43:17+00:00

Pull virtio updates from Michael Tsirkin: "Several new features here: - virtio-balloon supports new stats - vdpa supports setting mac address - vdpa/mlx5 suspend/resume as well as MKEY ops are now faster - virtio_fs supports new sysfs entries for queue info - virtio/vsock performance has been improved And fixes, cleanups all over the place" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (34 commits) vsock/virtio: avoid queuing packets when intermediate queue is empty vsock/virtio: refactor virtio_transport_send_pkt_work fw_cfg: Constify struct kobj_type vdpa/mlx5: Postpone MR deletion vdpa/mlx5: Introduce init/destroy for MR resources vdpa/mlx5: Rename mr_mtx -> lock vdpa/mlx5: Extract mr members in own resource struct vdpa/mlx5: Rename function vdpa/mlx5: Delete direct MKEYs in parallel vdpa/mlx5: Create direct MKEYs in parallel MAINTAINERS: add virtio-vsock driver in the VIRTIO CORE section virtio_fs: add sysfs entries for queue information virtio_fs: introduce virtio_fs_put_locked helper vdpa: Remove unused declarations vdpa/mlx5: Parallelize VQ suspend/resume for CVQ MQ command vdpa/mlx5: Small improvement for change_num_qps() vdpa/mlx5: Keep notifiers during suspend but ignore vdpa/mlx5: Parallelize device resume vdpa/mlx5: Parallelize device suspend vdpa/mlx5: Use async API for vq modify commands ...

virtio_pmem: Check device status before requesting flush

2024-09-10T06:51:47+00:00

If a pmem device is in a bad status, the driver side could wait for host ack forever in virtio_pmem_flush(), causing the system to hang. So add a status check in the beginning of virtio_pmem_flush() to return early if the device is not activated. Signed-off-by: Philip Chen Message-Id: <20240826215313.2673566-1-philipchen@chromium.org> Signed-off-by: Michael S. Tsirkin Acked-by: Pankaj Gupta

nvdimm: Remove dead code for ENODEV checking in scan_labels()

2024-08-21T21:06:43+00:00

The only way create_namespace_pmem() returns an ENODEV code is if select_pmem_id(nd_region, &uuid) returns ENODEV when its 2nd parameter is a null pointer. However, this is impossible because &uuid is always valid. Furthermore, create_namespace_pmem() is the only user of select_pmem_id(), it's safe to remove the 'return -ENODEV' branch. Signed-off-by: Li Zhijian Reviewed-by: Ira Weiny Link: https://patch.msgid.link/20240819062045.1481298-2-lizhijian@fujitsu.com Signed-off-by: Ira Weiny