In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
driver core: Avoid warning when removing a device while its supplier is unbinding<\/p>\n
During driver removal, the following warning can appear:
\n WARNING: CPU: 1 PID: 139 at drivers\/base\/core.c:1497 __device_links_no_driver+0xcc\/0xfc
\n …
\n Call trace:
\n __device_links_no_driver+0xcc\/0xfc (P)
\n device_links_driver_cleanup+0xa8\/0xf0
\n device_release_driver_internal+0x208\/0x23c
\n device_links_unbind_consumers+0xe0\/0x108
\n device_release_driver_internal+0xec\/0x23c
\n device_links_unbind_consumers+0xe0\/0x108
\n device_release_driver_internal+0xec\/0x23c
\n device_links_unbind_consumers+0xe0\/0x108
\n device_release_driver_internal+0xec\/0x23c
\n driver_detach+0xa0\/0x12c
\n bus_remove_driver+0x6c\/0xbc
\n driver_unregister+0x30\/0x60
\n pci_unregister_driver+0x20\/0x9c
\n lan966x_pci_driver_exit+0x18\/0xa90 [lan966x_pci]<\/p>\n
This warning is triggered when a consumer is removed because the links
\nstatus of its supplier is not DL_DEV_DRIVER_BOUND and the link flag
\nDL_FLAG_SYNC_STATE_ONLY is not set.<\/p>\n
The topology in terms of consumers\/suppliers used was the following
\n(consumer —> supplier):<\/p>\n
i2c ———–> OIC —-> PCI device
\n | ^
\n | |
\n +—> pinctrl —+<\/p>\n
When the PCI device is removed, the OIC (interrupt controller) has to be
\nremoved. In order to remove the OIC, pinctrl and i2c need to be removed
\nand to remove pinctrl, i2c need to be removed. The removal order is:
\n 1) i2c
\n 2) pinctrl
\n 3) OIC
\n 4) PCI device<\/p>\n
In details, the removal sequence is the following (with 0000:01:00.0 the
\nPCI device):
\n driver_detach: call device_release_driver_internal(0000:01:00.0)…
\n device_links_busy(0000:01:00.0):
\n links->status = DL_DEV_UNBINDING
\n device_links_unbind_consumers(0000:01:00.0):
\n 0000:01:00.0–oic link->status = DL_STATE_SUPPLIER_UNBIND
\n call device_release_driver_internal(oic)…
\n device_links_busy(oic):
\n links->status = DL_DEV_UNBINDING
\n device_links_unbind_consumers(oic):
\n oic–pinctrl link->status = DL_STATE_SUPPLIER_UNBIND
\n call device_release_driver_internal(pinctrl)…
\n device_links_busy(pinctrl):
\n links->status = DL_DEV_UNBINDING
\n device_links_unbind_consumers(pinctrl):
\n pinctrl–i2c link->status = DL_STATE_SUPPLIER_UNBIND
\n call device_release_driver_internal(i2c)…
\n device_links_busy(i2c): links->status = DL_DEV_UNBINDING
\n __device_links_no_driver(i2c)…
\n pinctrl–i2c link->status is DL_STATE_SUPPLIER_UNBIND
\n oic–i2c link->status is DL_STATE_ACTIVE
\n oic–i2c link->supplier->links.status is DL_DEV_UNBINDING<\/p>\n
The warning is triggered by the i2c removal because the OIC (supplier)
\nlinks status is not DL_DEV_DRIVER_BOUND. Its links status is indeed set
\nto DL_DEV_UNBINDING.<\/p>\n
It is perfectly legit to have the links status set to DL_DEV_UNBINDING
\nin that case. Indeed we had started to unbind the OIC which triggered
\nthe consumer unbinding and didn’t finish yet when the i2c is unbound.<\/p>\n
Avoid the warning when the supplier links status is set to
\nDL_DEV_UNBINDING and thus support this removal sequence without any
\nwarnings.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
driver core: Avoid warning when removing a device while its supplier is unbinding<\/p>\n
During driver removal, the following warning can<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-28711","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/28711","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=28711"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=28711"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=28711"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}