[ Upstream commit a4e772898f8bf2e7e1cf661a12c60a5612c4afab ]
One of the true positives that the cfg_access_lock lockdep effort
identified is this sequence:
WARNING: CPU: 14 PID: 1 at drivers/pci/pci.c:4886 pci_bridge_secondary_bus_reset+0x5d/0x70
RIP: 0010:pci_bridge_secondary_bus_reset+0x5d/0x70
Call Trace:
<TASK>
? __warn+0x8c/0x190
? pci_bridge_secondary_bus_reset+0x5d/0x70
? report_bug+0x1f8/0x200
? handle_bug+0x3c/0x70
? exc_invalid_op+0x18/0x70
? asm_exc_invalid_op+0x1a/0x20
? pci_bridge_secondary_bus_reset+0x5d/0x70
pci_reset_bus+0x1d8/0x270
vmd_probe+0x778/0xa10
pci_device_probe+0x95/0x120
Where pci_reset_bus() users are triggering unlocked secondary bus resets.
Ironically pci_bus_reset(), several calls down from pci_reset_bus(), uses
pci_bus_lock() before issuing the reset which locks everything *but* the
bridge itself.
For the same motivation as adding:
bridge = pci_upstream_bridge(dev);
if (bridge)
pci_dev_lock(bridge);
to pci_reset_function() for the "bus" and "cxl_bus" reset cases, add
pci_dev_lock() for @bus->self to pci_bus_lock().
Link: https://lore.kernel.org/r/171711747501.1628941.15217746952476635316.stgit@dwillia2-xfh.jf.intel.com
Reported-by: Imre Deak <imre.deak@intel.com>
Closes: http://lore.kernel.org/r/6657833b3b5ae_14984b29437@dwillia2-xfh.jf.intel.com.notmuch
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
[bhelgaas: squash in recursive locking deadlock fix from Keith Busch:
https://lore.kernel.org/r/20240711193650.701834-1-kbusch@meta.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Kalle Valo <kvalo@kernel.org>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 11a1f4bc47362700fcbde717292158873fb847ed upstream.
Keith reports a use-after-free when a DPC event occurs concurrently to
hot-removal of the same portion of the hierarchy:
The dpc_handler() awaits readiness of the secondary bus below the
Downstream Port where the DPC event occurred. To do so, it polls the
config space of the first child device on the secondary bus. If that
child device is concurrently removed, accesses to its struct pci_dev
cause the kernel to oops.
That's because pci_bridge_wait_for_secondary_bus() neglects to hold a
reference on the child device. Before v6.3, the function was only
called on resume from system sleep or on runtime resume. Holding a
reference wasn't necessary back then because the pciehp IRQ thread
could never run concurrently. (On resume from system sleep, IRQs are
not enabled until after the resume_noirq phase. And runtime resume is
always awaited before a PCI device is removed.)
However starting with v6.3, pci_bridge_wait_for_secondary_bus() is also
called on a DPC event. Commit 53b54ad074de ("PCI/DPC: Await readiness
of secondary bus after reset"), which introduced that, failed to
appreciate that pci_bridge_wait_for_secondary_bus() now needs to hold a
reference on the child device because dpc_handler() and pciehp may
indeed run concurrently. The commit was backported to v5.10+ stable
kernels, so that's the oldest one affected.
Add the missing reference acquisition.
Abridged stack trace:
BUG: unable to handle page fault for address: 00000000091400c0
CPU: 15 PID: 2464 Comm: irq/53-pcie-dpc 6.9.0
RIP: pci_bus_read_config_dword+0x17/0x50
pci_dev_wait()
pci_bridge_wait_for_secondary_bus()
dpc_reset_link()
pcie_do_recovery()
dpc_handler()
Fixes: 53b54ad074de ("PCI/DPC: Await readiness of secondary bus after reset")
Closes: https://lore.kernel.org/r/20240612181625.3604512-3-kbusch@meta.com/
Link: https://lore.kernel.org/linux-pci/8e4bcd4116fd94f592f2bf2749f168099c480ddf.1718707743.git.lukas@wunner.de
Reported-by: Keith Busch <kbusch@kernel.org>
Tested-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 256df20c590bf0e4d63ac69330cf23faddac3e08 ]
Hewlett-Packard HP Pavilion 17 Notebook PC/1972 is an Intel Ivy Bridge
system with a muxless AMD Radeon dGPU. Attempting to use the dGPU fails
with the following sequence:
ACPI Error: Aborting method \AMD3._ON due to previous error (AE_AML_LOOP_TIMEOUT) (20230628/psparse-529)
radeon 0000:01:00.0: not ready 1023ms after resume; waiting
radeon 0000:01:00.0: not ready 2047ms after resume; waiting
radeon 0000:01:00.0: not ready 4095ms after resume; waiting
radeon 0000:01:00.0: not ready 8191ms after resume; waiting
radeon 0000:01:00.0: not ready 16383ms after resume; waiting
radeon 0000:01:00.0: not ready 32767ms after resume; waiting
radeon 0000:01:00.0: not ready 65535ms after resume; giving up
radeon 0000:01:00.0: Unable to change power state from D3cold to D0, device inaccessible
The issue is that the Root Port the dGPU is connected to can't handle the
transition from D3cold to D0 so the dGPU can't properly exit runtime PM.
The existing logic in pci_bridge_d3_possible() checks for systems that are
newer than 2015 to decide that D3 is safe. This would nominally work for
an Ivy Bridge system (which was discontinued in 2015), but this system
appears to have continued to receive BIOS updates until 2017 and so this
existing logic doesn't appropriately capture it.
Add the system to bridge_d3_blacklist to prevent D3cold from being used.
Link: https://lore.kernel.org/r/20240307163709.323-1-mario.limonciello@amd.com
Reported-by: Eric Heintzmann <heintzmann.eric@free.fr>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3229
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Eric Heintzmann <heintzmann.eric@free.fr>
Signed-off-by: Sasha Levin <sashal@kernel.org>
