kernel/linux.git/drivers/usb/core/hcd.c, branch linux-7.0.y

usb: hcd: queue wakeup_work to system_freezable_wq workqueue

2026-03-18T15:17:08+00:00

After commit 4fb352df14de ("PM: sleep: Do not flag runtime PM workqueue as freezable"), pm_wq workqueue will be unfreezable during system pm. This brings issue as below: [ 344.255749] ------------[ cut here ]------------ [ 344.277740] URB 000000004aae4ad1 submitted while active [ 344.282996] WARNING: drivers/usb/core/urb.c:379 at usb_submit_urb+0x5a4/0x5e0, CPU#2: kworker/u16:14/964 [ 344.292477] Modules linked in: [ 344.295532] CPU: 2 UID: 0 PID: 964 Comm: kworker/u16:14 Not tainted 7.0.0-rc2-next-20260303-00006-gf03fe0b53b39-dirty #100 PREEMPT [ 344.307341] Hardware name: NXP i.MX943 EVK board (DT) [ 344.312386] Workqueue: async async_run_entry_fn [ 344.316919] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 344.323862] pc : usb_submit_urb+0x5a4/0x5e0 [ 344.328046] lr : usb_submit_urb+0x5a4/0x5e0 [ 344.332217] sp : ffff800083283b30 [ 344.335528] x29: ffff800083283b30 x28: ffff000082631000 x27: 0000000000000000 [ 344.342661] x26: 0000000000000003 x25: 0000000000000c00 x24: 0000000000000000 [ 344.349793] x23: 0000000000000004 x22: 0000000000000010 x21: 0000000000000000 [ 344.356917] x20: 0000000000000002 x19: ffff00008253ce40 x18: ffff000089e4eec0 [ 344.364050] x17: 000000040044ffff x16: 000005d9d87f6289 x15: 0000000000000000 [ 344.371174] x14: ffff000089e4eec0 x13: 6576697463612065 x12: 6c69687720646574 [ 344.378298] x11: 0000000000000058 x10: 0000000000000001 x9 : 0000000000000001 [ 344.385431] x8 : 0000000000000000 x7 : 0000005028dd0800 x6 : 0000000000000002 [ 344.392563] x5 : ffffc48f74e9daf8 x4 : 0000000000000000 x3 : 0000000000000000 [ 344.399696] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000089e4ee40 [ 344.406835] Call trace: [ 344.409280] usb_submit_urb+0x5a4/0x5e0 (P) [ 344.413456] hub_activate+0x268/0x878 [ 344.417116] hub_resume+0x5c/0x10c [ 344.420522] usb_resume_interface.isra.0+0xa8/0x110 [ 344.425393] usb_resume_both+0x10c/0x1e0 [ 344.429310] usb_resume+0x1c/0x70 [ 344.432621] usb_dev_resume+0x14/0x20 [ 344.436278] dpm_run_callback.isra.0+0x38/0xf8 [ 344.440715] device_resume+0xec/0x1e8 [ 344.444373] async_resume+0x20/0x38 [ 344.447848] async_run_entry_fn+0x34/0xe0 [ 344.451852] process_one_work+0x150/0x290 [ 344.455856] worker_thread+0x18c/0x300 [ 344.459600] kthread+0x118/0x124 [ 344.462824] ret_from_fork+0x10/0x20 The reason is if the host controller resume routine xhci_resume() call usb_hcd_resume_root_hub(), wakeup_work will be queued and run immediately. Then usb_autoresume_device() will be called and usb device will exit runtime suspended state (if it was suspended before). For a hub device, hub_resume()/hub_reset_resume() will be called accordingly. After the host controller device system resume is finished, the root hub usb device "usb1" will do system resume too. Then hub_resume() will be called again. Above sequence will cause hub->urb to be submitted twice. To avoid this issue, restore the previous behavior by queuing wakeup_work to system_freezable_wq workqueue. Acked-by: Alan Stern Fixes: 4fb352df14de ("PM: sleep: Do not flag runtime PM workqueue as freezable") Cc: stable Signed-off-by: Xu Yang Link: https://patch.msgid.link/20260316094811.1559471-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

Convert more 'alloc_obj' cases to default GFP_KERNEL arguments

2026-02-22T04:03:00+00:00

This converts some of the visually simpler cases that have been split over multiple lines. I only did the ones that are easy to verify the resulting diff by having just that final GFP_KERNEL argument on the next line. Somebody should probably do a proper coccinelle script for this, but for me the trivial script actually resulted in an assertion failure in the middle of the script. I probably had made it a bit _too_ trivial. So after fighting that far a while I decided to just do some of the syntactically simpler cases with variations of the previous 'sed' scripts. The more syntactically complex multi-line cases would mostly really want whitespace cleanup anyway. Signed-off-by: Linus Torvalds

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

USB: HCD: remove logic about which hcd is loaded

2026-01-14T14:59:00+00:00

It turns out that warning about which USB host controller is loaded before another one doesn't really matter. All that really is needed is the PCI softdep module loading logic, which has been present in the kernel ever since commit 05c92da0c524 ("usb: ohci/uhci - add soft dependencies on ehci_pci") So remove the warning messages, they are not useful, not needed, and only confuse people. As can be seen in the discussion at https://lore.kernel.org/r/20251230080014.3934590-1-chenhuacai@loongson.cn Cc: Huacai Chen Suggested-by: Alan Stern Reviewed-by: Huacai Chen Link: https://patch.msgid.link/2026010739-diffuser-shelter-e31c@gregkh Signed-off-by: Greg Kroah-Hartman

usb: core: Drop spaces after function names

2025-10-13T07:11:48+00:00

Drop spaces after function name to comply with the coding style. Signed-off-by: Claudiu Beznea Link: https://lore.kernel.org/r/20250924091036.1319161-1-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman

USB: core: Update kerneldoc for usb_hcd_giveback_urb()

2025-08-19T10:29:04+00:00

The kerneldoc added for usb_hcd_giveback_urb() by commit 41631d3616c3 ("usb: core: Replace in_interrupt() in comments") is unclear and incorrect. Update the text for greater clarity and to say that URBs for a root hub will always use a BH context for their completion. Signed-off-by: Alan Stern Link: https://lore.kernel.org/r/41eaae05-116a-4568-940c-eeb94ab6baa0@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman

kcov, usb: Don't disable interrupts in kcov_remote_start_usb_softirq()

2025-08-13T15:18:43+00:00

kcov_remote_start_usb_softirq() the begin of urb's completion callback. HCDs marked HCD_BH will invoke this function from the softirq and in_serving_softirq() will detect this properly. Root-HUB (RH) requests will not be delayed to softirq but complete immediately in IRQ context. This will confuse kcov because in_serving_softirq() will report true if the softirq is served after the hardirq and if the softirq got interrupted by the hardirq in which currently runs. This was addressed by simply disabling interrupts in kcov_remote_start_usb_softirq() which avoided the interruption by the RH while a regular completion callback was invoked. This not only changes the behaviour while kconv is enabled but also breaks PREEMPT_RT because now sleeping locks can no longer be acquired. Revert the previous fix. Address the issue by invoking kcov_remote_start_usb() only if the context is just "serving softirqs" which is identified by checking in_serving_softirq() and in_hardirq() must be false. Fixes: f85d39dd7ed89 ("kcov, usb: disable interrupts in kcov_remote_start_usb_softirq") Cc: stable Reported-by: Yunseong Kim Closes: https://lore.kernel.org/all/20250725201400.1078395-2-ysk@kzalloc.com/ Tested-by: Yunseong Kim Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20250811082745.ycJqBXMs@linutronix.de Signed-off-by: Greg Kroah-Hartman

usb: core: hcd: fix accessing unmapped memory in SINGLE_STEP_SET_FEATURE test

2025-08-13T15:16:22+00:00

The USB core will unmap urb->transfer_dma after SETUP stage completes. Then the USB controller will access unmapped memory when it received device descriptor. If iommu is equipped, the entire test can't be completed due to the memory accessing is blocked. Fix it by calling map_urb_for_dma() again for IN stage. To reduce redundant map for urb->transfer_buffer, this will also set URB_NO_TRANSFER_DMA_MAP flag before first map_urb_for_dma() to skip dma map for urb->transfer_buffer and clear URB_NO_TRANSFER_DMA_MAP flag before second map_urb_for_dma(). Fixes: 216e0e563d81 ("usb: core: hcd: use map_urb_for_dma for single step set feature urb") Cc: stable Reviewed-by: Jun Li Signed-off-by: Xu Yang Acked-by: Alan Stern Link: https://lore.kernel.org/r/20250806083955.3325299-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

usb: core: add dma-noncoherent buffer alloc and free API

2025-07-09T10:15:56+00:00

This will add usb_alloc_noncoherent() and usb_free_noncoherent() functions to support alloc and free buffer in a dma-noncoherent way. To explicit manage the memory ownership for the kernel and device, this will also add usb_dma_noncoherent_sync_for_cpu/device() functions and call it at proper time. The management requires the user save sg_table returned by usb_alloc_noncoherent() to urb->sgt. Signed-off-by: Xu Yang Reviewed-by: Alan Stern Link: https://lore.kernel.org/r/20250704095751.73765-2-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman