[REGRESSION 6.17-rc3] usb/xhci: possible memory leak after suspend/resume cycle.

[David Wang <00107082@163.com>]

Hi,

I have been watching kernel memory usage for drivers for a while, via /proc/allocinfo.
After upgrade to 6.17-rc3, I notice memory usage behavior changes for usb drivers:

Before rc3, after several suspend/resume cycles, usb devices's memory usage is very stable:

       40960        5 drivers/usb/host/xhci-mem.c:980 [xhci_hcd] func:xhci_alloc_virt_device 9
        1024        1 drivers/usb/host/xhci-mem.c:841 [xhci_hcd] func:xhci_alloc_tt_info 2
         320       10 drivers/usb/host/xhci-mem.c:461 [xhci_hcd] func:xhci_alloc_container_ctx 31
        1920       15 drivers/usb/host/xhci-mem.c:377 [xhci_hcd] func:xhci_ring_alloc 31
         112       12 drivers/usb/host/xhci-mem.c:49 [xhci_hcd] func:xhci_segment_alloc 32
        1792       28 drivers/usb/host/xhci-mem.c:38 [xhci_hcd] func:xhci_segment_alloc 59

But with rc3, the memory usage increase after each suspend/resume cycle: 

#1:
       49152        6 drivers/usb/host/xhci-mem.c:980 [xhci_hcd] func:xhci_alloc_virt_device 9
        1024        1 drivers/usb/host/xhci-mem.c:841 [xhci_hcd] func:xhci_alloc_tt_info 2
         384       12 drivers/usb/host/xhci-mem.c:461 [xhci_hcd] func:xhci_alloc_container_ctx 32
        2176       17 drivers/usb/host/xhci-mem.c:377 [xhci_hcd] func:xhci_ring_alloc 32
         128       14 drivers/usb/host/xhci-mem.c:49 [xhci_hcd] func:xhci_segment_alloc 34
        2048       32 drivers/usb/host/xhci-mem.c:38 [xhci_hcd] func:xhci_segment_alloc 61
#2:
       57344        7 drivers/usb/host/xhci-mem.c:980 [xhci_hcd] func:xhci_alloc_virt_device 13
        1024        1 drivers/usb/host/xhci-mem.c:841 [xhci_hcd] func:xhci_alloc_tt_info 3
         448       14 drivers/usb/host/xhci-mem.c:461 [xhci_hcd] func:xhci_alloc_container_ctx 46
        2432       19 drivers/usb/host/xhci-mem.c:377 [xhci_hcd] func:xhci_ring_alloc 43
         144       16 drivers/usb/host/xhci-mem.c:49 [xhci_hcd] func:xhci_segment_alloc 44
        2304       36 drivers/usb/host/xhci-mem.c:38 [xhci_hcd] func:xhci_segment_alloc 82
#3:
       65536        8 drivers/usb/host/xhci-mem.c:980 [xhci_hcd] func:xhci_alloc_virt_device 17
        1024        1 drivers/usb/host/xhci-mem.c:841 [xhci_hcd] func:xhci_alloc_tt_info 4
         512       16 drivers/usb/host/xhci-mem.c:461 [xhci_hcd] func:xhci_alloc_container_ctx 60
        2688       21 drivers/usb/host/xhci-mem.c:377 [xhci_hcd] func:xhci_ring_alloc 54
         160       18 drivers/usb/host/xhci-mem.c:49 [xhci_hcd] func:xhci_segment_alloc 54
        2560       40 drivers/usb/host/xhci-mem.c:38 [xhci_hcd] func:xhci_segment_alloc 103

The memory increasing pattern keeps going on for each suspend/resume afterwards, I am not
sure whether those memory would be released sometime later.

And in kernel log, two lines of error always showed up after suspend/resume:

	[  295.613598] xhci_hcd 0000:03:00.0: dma_pool_destroy xHCI ring segments busy
	[  295.613605] xhci_hcd 0000:03:00.0: dma_pool_destroy xHCI input/output contexts busy

And bisect narrow down to commit 2eb03376151bb8585caa23ed2673583107bb5193(
"usb: xhci: Fix slot_id resource race conflict"):

	git bisect start 'drivers/usb'
	# status: waiting for both good and bad commits
	# good: [c17b750b3ad9f45f2b6f7e6f7f4679844244f0b9] Linux 6.17-rc2
	git bisect good c17b750b3ad9f45f2b6f7e6f7f4679844244f0b9
	# status: waiting for bad commit, 1 good commit known
	# bad: [1b237f190eb3d36f52dffe07a40b5eb210280e00] Linux 6.17-rc3
	git bisect bad 1b237f190eb3d36f52dffe07a40b5eb210280e00
	# good: [e86ba12cf84ab9cf42fbc2382235fa7ba616e18b] Merge tag 'nfs-for-6.17-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
	git bisect good e86ba12cf84ab9cf42fbc2382235fa7ba616e18b
	# good: [471b25a2fcbb25dccd7c9bece30313f2440a554e] Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd
	git bisect good 471b25a2fcbb25dccd7c9bece30313f2440a554e
	# good: [52025b8fc992972168128be40bffee7eafa532b5] Merge tag 'driver-core-6.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
	git bisect good 52025b8fc992972168128be40bffee7eafa532b5
	# bad: [8004d08330e1aa7ae797778509e864f7ac3da687] Merge tag 'usb-6.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
	git bisect bad 8004d08330e1aa7ae797778509e864f7ac3da687
	# good: [a381c6d6f646226924809d0ad01a9465786da463] usb: typec: maxim_contaminant: re-enable cc toggle if cc is open and port is clean
	git bisect good a381c6d6f646226924809d0ad01a9465786da463
	# good: [4013aef2ced9b756a410f50d12df9ebe6a883e4a] ftrace: Fix potential warning in trace_printk_seq during ftrace_dump
	git bisect good 4013aef2ced9b756a410f50d12df9ebe6a883e4a
	# bad: [2eb03376151bb8585caa23ed2673583107bb5193] usb: xhci: Fix slot_id resource race conflict
	git bisect bad 2eb03376151bb8585caa23ed2673583107bb5193
	# good: [309b6341d5570fb2b41b923de2fc9bb147106b80] usb: typec: fusb302: Revert incorrect threaded irq fix
	git bisect good 309b6341d5570fb2b41b923de2fc9bb147106b80
	# first bad commit: [2eb03376151bb8585caa23ed2673583107bb5193] usb: xhci: Fix slot_id resource race conflict



Thanks
David