04e85a3285
[ 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> |
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.. | ||
controller | ||
endpoint | ||
hotplug | ||
pcie | ||
switch | ||
Kconfig | ||
Makefile | ||
access.c | ||
ats.c | ||
bus.c | ||
ecam.c | ||
host-bridge.c | ||
iov.c | ||
irq.c | ||
mmap.c | ||
msi.c | ||
of.c | ||
p2pdma.c | ||
pci-acpi.c | ||
pci-bridge-emul.c | ||
pci-bridge-emul.h | ||
pci-driver.c | ||
pci-label.c | ||
pci-mid.c | ||
pci-pf-stub.c | ||
pci-stub.c | ||
pci-sysfs.c | ||
pci.c | ||
pci.h | ||
probe.c | ||
proc.c | ||
quirks.c | ||
remove.c | ||
rom.c | ||
search.c | ||
setup-bus.c | ||
setup-irq.c | ||
setup-res.c | ||
slot.c | ||
syscall.c | ||
vc.c | ||
vpd.c | ||
xen-pcifront.c |