Liguang Zhang 312366a681 PCI: pciehp: Clear cmd_busy bit in polling mode ... commit 92912b1751 upstream. Writes to a Downstream Port's Slot Control register are PCIe hotplug "commands." If the Port supports Command Completed events, software must wait for a command to complete before writing to Slot Control again. pcie_do_write_cmd() sets ctrl->cmd_busy when it writes to Slot Control. If software notification is enabled, i.e., PCI_EXP_SLTCTL_HPIE and PCI_EXP_SLTCTL_CCIE are set, ctrl->cmd_busy is cleared by pciehp_isr(). But when software notification is disabled, as it is when pcie_init() powers off an empty slot, pcie_wait_cmd() uses pcie_poll_cmd() to poll for command completion, and it neglects to clear ctrl->cmd_busy, which leads to spurious timeouts: pcieport 0000:00:03.0: pciehp: Timeout on hotplug command 0x01c0 (issued 2264 msec ago) pcieport 0000:00:03.0: pciehp: Timeout on hotplug command 0x05c0 (issued 2288 msec ago) Clear ctrl->cmd_busy in pcie_poll_cmd() when it detects a Command Completed event (PCI_EXP_SLTSTA_CC). [bhelgaas: commit log] Fixes: a5dd4b4b05 ("PCI: pciehp: Wait for hotplug command completion where necessary") Link: https://lore.kernel.org/r/20211111054258.7309-1-zhangliguang@linux.alibaba.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=215143 Link: https://lore.kernel.org/r/20211126173309.GA12255@wunner.de Signed-off-by: Liguang Zhang <zhangliguang@linux.alibaba.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-04-20 09:08:12 +02:00
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acpi_pcihp.c
acpiphp.h
acpiphp_core.c
acpiphp_glue.c	ACPI / hotplug / PCI: Fix reference count leak in enable_slot()	2021-05-22 10:57:42 +02:00
acpiphp_ibm.c
cpci_hotplug.h
cpci_hotplug_core.c
cpci_hotplug_pci.c
cpcihp_generic.c
cpcihp_zt5550.c
cpcihp_zt5550.h
cpqphp.h
cpqphp_core.c
cpqphp_ctrl.c
cpqphp_nvram.c
cpqphp_nvram.h
cpqphp_pci.c
cpqphp_sysfs.c
ibmphp.h
ibmphp_core.c
ibmphp_ebda.c
ibmphp_hpc.c
ibmphp_pci.c
ibmphp_res.c
Kconfig
Makefile
pci_hotplug_core.c
pciehp.h
pciehp_core.c
pciehp_ctrl.c
pciehp_hpc.c	PCI: pciehp: Clear cmd_busy bit in polling mode	2022-04-20 09:08:12 +02:00
pciehp_pci.c
pcihp_skeleton.c
pnv_php.c
rpadlpar.h
rpadlpar_core.c
rpadlpar_sysfs.c
rpaphp.h
rpaphp_core.c
rpaphp_pci.c
rpaphp_slot.c
s390_pci_hpc.c
sgi_hotplug.c
shpchp.h
shpchp_core.c
shpchp_ctrl.c
shpchp_hpc.c
shpchp_pci.c
shpchp_sysfs.c