FYI. There's more information and analysis, but no resolution yet, in the bugzilla. ---------- Forwarded message ---------- From: <bugzilla-daemon@xxxxxxxxxxxxxxxxxxx> Date: Wed, Jun 10, 2015 at 11:25 AM Subject: [Bug 99751] New: Enormous resume delay, unless pcie_ports=compat To: bhelgaas@xxxxxxxxxx https://bugzilla.kernel.org/show_bug.cgi?id=99751 Bug ID: 99751 Summary: Enormous resume delay, unless pcie_ports=compat Product: Drivers Version: 2.5 Kernel Version: 3.15 through 4.1rc5 Hardware: All OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: PCI Assignee: drivers_pci@xxxxxxxxxxxxxxxxxxxx Reporter: lenb@xxxxxxxxxx Regression: No Created attachment 179451 --> https://bugzilla.kernel.org/attachment.cgi?id=179451&action=edit lspci -vvv output On a Dell XPS11 laptop, pcieport 0000:00:1c.0 takes several seconds to resume from suspend. Booting with "pcie_ports=compat", or building with CONFIG_HOTPLUG_PCI_PCIE=n makes this delay go away. I've tested Linux-3.14.44 and do not see this delay. I've tested Linux-3.15.0 and others up through 4.1-rc5 and I do see this delay. So I'll mark this as a regression. while I use analyze_suspend.py to trace resume, initcall_debug is sufficient to show this delay in dmesg, and I notice some additional PCI warnings there: [ 55.897986] pciehp 0000:00:1c.0:pcie04: Link Training Error occurs [ 55.897988] pciehp 0000:00:1c.0:pcie04: Failed to check link status [ 55.897992] call 0000:00:1c.0+ returned 0 after 2197660 usecs (yes, that is 2.19 SECONDS -- where anything> 50ms for resume is considered slow) Unclear (to me) what pcie04 is... $ lspci 00:00.0 Host bridge: Intel Corporation Haswell-ULT DRAM Controller (rev 0b) 00:02.0 VGA compatible controller: Intel Corporation Device 0a1e (rev 0b) 00:03.0 Audio device: Intel Corporation Haswell-ULT HD Audio Controller (rev 0b) 00:04.0 Signal processing controller: Intel Corporation Device 0a03 (rev 0b) 00:14.0 USB controller: Intel Corporation 8 Series USB xHCI HC (rev 04) 00:16.0 Communication controller: Intel Corporation 8 Series HECI #0 (rev 04) 00:1b.0 Audio device: Intel Corporation 8 Series HD Audio Controller (rev 04) 00:1c.0 PCI bridge: Intel Corporation 8 Series PCI Express Root Port 1 (rev e4) 00:1c.1 PCI bridge: Intel Corporation 8 Series PCI Express Root Port 2 (rev e4) 00:1c.3 PCI bridge: Intel Corporation 8 Series PCI Express Root Port 4 (rev e4) 00:1d.0 USB controller: Intel Corporation 8 Series USB EHCI #1 (rev 04) 00:1f.0 ISA bridge: Intel Corporation 8 Series LPC Controller (rev 04) 00:1f.2 SATA controller: Intel Corporation 8 Series SATA Controller 1 [AHCI mode] (rev 04) 00:1f.3 SMBus: Intel Corporation 8 Series SMBus Controller (rev 04) 00:1f.6 Signal processing controller: Intel Corporation 8 Series Thermal (rev 04) 05:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5249 PCI Express Card Reader (rev 01) 07:00.0 Network controller: Intel Corporation Wireless 7260 (rev 6b) This 04 item appears under 1c.0 when I ask lspci about topology: $ lspci -tv -[0000:00]-+-00.0 Intel Corporation Haswell-ULT DRAM Controller +-02.0 Intel Corporation Device 0a1e +-03.0 Intel Corporation Haswell-ULT HD Audio Controller +-04.0 Intel Corporation Device 0a03 +-14.0 Intel Corporation 8 Series USB xHCI HC +-16.0 Intel Corporation 8 Series HECI #0 +-1b.0 Intel Corporation 8 Series HD Audio Controller +-1c.0-[04]-- +-1c.1-[05]----00.0 Realtek Semiconductor Co., Ltd. RTS5249 PCI Express Card Reader +-1c.3-[07]----00.0 Intel Corporation Wireless 7260 +-1d.0 Intel Corporation 8 Series USB EHCI #1 +-1f.0 Intel Corporation 8 Series LPC Controller +-1f.2 Intel Corporation 8 Series SATA Controller 1 [AHCI mode] +-1f.3 Intel Corporation 8 Series SMBus Controller \-1f.6 Intel Corporation 8 Series Thermal -- You are receiving this mail because: You are watching the assignee of the bug. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
