Dexuan Cui 0d5acba633 Drivers: hv: vmbus: Export hv_vmbus_exists() and use it in pci-hyperv ... With commit f84b21da36 ("PCI: hv: Don't load the driver for baremetal root partition"), the bare metal Linux root partition won't use the pci-hyperv driver, but when a Linux VM runs on the Linux root partition, pci-hyperv's module_init function init_hv_pci_drv() can still run, e.g. in the case of CONFIG_PCI_HYPERV=y, even if the VMBus driver is not used in such a VM (i.e. the hv_vmbus driver's init function returns -ENODEV due to vmbus_root_device being NULL). In such a Linux VM, init_hv_pci_drv() runs with a side effect: the 3 hvpci_block_ops callbacks are set to functions that depend on hv_vmbus. Later, when the MLX driver in such a VM invokes the callbacks, e.g. in drivers/net/ethernet/mellanox/mlx5/core/lib/hv.c: mlx5_hv_register_invalidate(), hvpci_block_ops.reg_blk_invalidate() is hv_register_block_invalidate() rather than a NULL function pointer, and hv_register_block_invalidate() assumes that it can find a struct hv_pcibus_device from pdev->bus->sysdata, which is false in such a VM. Consequently, hv_register_block_invalidate() -> get_pcichild_wslot() -> spin_lock_irqsave() may hang since it can be accessing an invalid spinlock pointer. Fix the issue by exporting hv_vmbus_exists() and using it in pci-hyperv: hv_root_partition() is true and hv_nested is false ==> hv_vmbus_exists() is false. hv_root_partition() is true and hv_nested is true ==> hv_vmbus_exists() is true. hv_root_partition() is false ==> hv_vmbus_exists() is true. While at it, rename vmbus_exists() to hv_vmbus_exists() to follow the convention that all public functions have the hv_ prefix; also change the return value's type from int to bool to make the code more readable; also move the two pr_info() calls. Reported-by: Mukesh Rathor <mrathor@linux.microsoft.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>		2026-04-14 04:42:44 +00:00
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acpi	…
asm-generic	…
clocksource	…
crypto	crypto: algif_aead - Revert to operating out-of-place	2026-03-31 17:11:47 +09:00
cxl	…
drm	drm/dp: Add definition for Panel Replay full-line granularity	2026-03-04 15:26:08 +02:00
dt-bindings	reset: spacemit: k3: Decouple composite reset lines	2026-03-23 12:25:47 +01:00
hyperv	mshv: Fix infinite fault loop on permission-denied GPA intercepts	2026-04-04 05:25:53 +00:00
keys	…
kunit	…
kvm	…
linux	Drivers: hv: vmbus: Export hv_vmbus_exists() and use it in pci-hyperv	2026-04-14 04:42:44 +00:00
math-emu	…
media	…
memory	…
misc	…
net	vfs-7.0-rc8.fixes	2026-04-10 08:40:49 -07:00
pcmcia	…
ras	…
rdma	…
rv	…
scsi	…
soc	…
sound	ASoC: SDCA: Unregister IRQ handlers on module remove	2026-04-08 16:55:30 +01:00
target	…
trace	rxrpc: Fix to request an ack if window is limited	2026-04-08 18:44:33 -07:00
uapi	s390:	2026-04-11 11:45:20 -07:00
ufs	…
vdso	…
video	…
xen	xen/xenbus: better handle backend crash	2026-03-04 15:31:40 +01:00
Kbuild	…