On Tue, Sep 15, 2020 at 04:15:15PM +0200, Jinpu Wang wrote: > We are testing PCIe nvme SSD hotplug, it works out of box with kernel 5.4.62, > dmesg during the hotplug: [...] > But with kernel 4.19.133, pcieport core doesn't print anything, is > there known problem with kernel 4.19 support for pcie hotplug, do we > need to backport some fixes from newer kernel to make it work? No known problem. Please open a bug on bugzilla.kernel.org and attach full dmesg output for 5.4.62 and 4.19.133, as well as lspci -vv output. You may want to add the following to the kernel command line: ignore_loglevel log_bug_len=10M "dyndbg=file drivers/pci/* +p" pciehp.pciehp_debug=1 > [ 683.218554] pcieport 0000:16:00.0: pciehp: Slot(0-3): Card present > [ 683.218555] pcieport 0000:16:00.0: pciehp: Slot(0-3): Link Up > [ 683.271702] pcieport 0000:16:00.0: pciehp: Timeout on hotplug > command 0x17e1 (issued 73280 msec ago) > [ 686.301874] pcieport 0000:16:00.0: pciehp: Timeout on hotplug > command 0x13e1 (issued 3030 msec ago) > [ 686.361894] pcieport 0000:16:00.0: pciehp: Timeout on hotplug > command 0x13e1 (issued 3090 msec ago) Those timeouts look suspicious. Perhaps the hotplug controller claims to support Command Completed Support, but in reality does not? > CONFIG_HOTPLUG_PCI=y > CONFIG_HOTPLUG_PCI_ACPI=y > CONFIG_HOTPLUG_PCI_ACPI_IBM=m > CONFIG_HOTPLUG_PCI_CPCI=y > CONFIG_HOTPLUG_PCI_CPCI_ZT5550=m > CONFIG_HOTPLUG_PCI_CPCI_GENERIC=m > CONFIG_HOTPLUG_PCI_SHPC=y > CONFIG_HOTPLUG_PCI_PCIE=y You may not need ACPI_IBM, CPCI, SHPC. Thanks, Lukas
