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Linux kernel
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Before 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0"),
pci_sriov_set_totalvfs(pdev, 0) meant "we can enable TotalVFs virtual
functions". After 8d85a7a4f2c9, it means "we can't enable *any* VFs".
That broke this scenario where nfp intends to remove any limit on the
number of VFs that can be enabled:
nfp_pci_probe
nfp_pcie_sriov_read_nfd_limit
nfp_rtsym_read_le("nfd_vf_cfg_max_vfs", &err)
pci_sriov_set_totalvfs(pf->pdev, 0) # if FW didn't expose a limit
...
# userspace writes N to sysfs "sriov_numvfs":
sriov_numvfs_store
pci_sriov_get_totalvfs # now returns 0
return -ERANGE
Prior to 8d85a7a4f2c9, pci_sriov_get_totalvfs() returned TotalVFs, but it
now returns 0.
Remove the pci_sriov_set_totalvfs(pdev, 0) calls so we don't limit the
number of VFs that can be enabled.
Fixes: 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The TotalVFs register in the SR-IOV capability is the hardware limit on the
number of VFs. A PF driver can limit the number of VFs further with
pci_sriov_set_totalvfs(). When the PF driver is removed, reset any VF
limit that was imposed by the driver because that limit may not apply to
other drivers.
Before 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0"),
pci_sriov_set_totalvfs(pdev, 0) meant "we can enable TotalVFs virtual
functions", and the nfp driver used that to remove the VF limit when the
driver unloads.
8d85a7a4f2c9 broke that because instead of removing the VF limit,
pci_sriov_set_totalvfs(pdev, 0) actually sets the limit to zero, and that
limit persists even if another driver is loaded.
We could fix that by making the nfp driver reset the limit when it unloads,
but it seems more robust to do it in the PCI core instead of relying on the
driver.
The regression scenario is:
nfp_pci_probe (driver 1)
...
nfp_pci_remove
pci_sriov_set_totalvfs(pf->pdev, 0) # limits VFs to 0
...
nfp_pci_probe (driver 2)
nfp_rtsym_read_le("nfd_vf_cfg_max_vfs")
# no VF limit from firmware
Now driver 2 is broken because the VF limit is still 0 from driver 1.
Fixes: 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
[bhelgaas: changelog, rename functions]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The call to of_get_next_child() returns a node pointer with refcount
incremented thus it must be explicitly decremented here in the error
path and after the last usage.
Fixes: d3c68e0a7e34 ("PCI: faraday: Add Faraday Technology FTPCI100 PCI Host Bridge driver")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
The call to of_get_next_child() returns a node pointer with
refcount incremented thus it must be explicitly decremented
here after the last usage.
Fixes: ab597d35ef11 ("PCI: xilinx-nwl: Add support for Xilinx NWL PCIe Host Controller")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The call to of_get_next_child() returns a node pointer with refcount
incremented thus it must be explicitly decremented here after the last
usage.
Fixes: 8961def56845 ("PCI: xilinx: Add Xilinx AXI PCIe Host Bridge IP driver")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
[lorenzo.pieralisi@arm.com: reworked commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We need to use list_for_each_entry_safe() because the
pci_ep_cfs_remove_epf_group() function frees "group".
Fixes: ef1433f717a2 ("PCI: endpoint: Create configfs entry for each pci_epf_device_id table entry")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
PCIE_DW_PLAT_HOST does not have any platform dependency, so it should
not default to yes.
Fixes: 1d906b22076e12cf ("PCI: dwc: Add support for EP mode")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
If the Gen3 PHY fails to power up, the code does not undo the
initialization caused by phy_init(). Add the missing failure
handling to the rcar_pcie_phy_init_gen3() function.
Fixes: 517ca93a7159 ("PCI: rcar: Add R-Car gen3 PHY support")
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
If anything fails past phy_init_fn() and the system is a Gen3 with
a PHY, the PHY will be left on and inited. This is caused by the
phy_init_fn, which is in fact a pointer to rcar_pcie_phy_init_gen3()
function, which starts the PHY, yet has no counterpart in the failpath.
Add that counterpart.
Fixes: 517ca93a7159 ("PCI: rcar: Add R-Car gen3 PHY support")
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Commit 51bc085d6454 ("PCI: Improve host drivers compile test coverage")
added configuration options to allow PCI host controller drivers to be
compile tested on all architectures.
Some host controller drivers (eg PCIE_ALTERA) config entries select the
PCI_DOMAINS config option to enable PCI domains management in the kernel.
Now that host controller drivers can be compiled on all architectures, this
triggers build regressions on arches that do not implement the PCI_DOMAINS
required API (ie pci_domain_nr()):
drivers/ata/pata_ali.c: In function 'ali_init_chipset':
drivers/ata/pata_ali.c:469:38: error: implicit declaration of function 'pci_domain_nr'; did you mean 'pci_iomap_wc'?
Furthemore, some software configurations (ie Jailhouse) require a
PCI_DOMAINS enabled kernel to configure multiple host controllers without
having an explicit dependency on the ARM platform on which they run.
Make PCI_DOMAINS a visible configuration option on ARM so that software
configurations that need it can manually select it and move the PCI_DOMAINS
selection from PCI controllers configuration file to ARM sub-arch config
entries that currently require it, fixing the issue.
Fixes: 51bc085d6454 ("PCI: Improve host drivers compile test coverage")
Link: https://lkml.kernel.org/r/20180612170229.GA10141@roeck-us.net
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>
Acked-by: Rob Herring <robh@kernel.org>
Cc: Scott Branden <scott.branden@broadcom.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Guenter Roeck <linux@roeck-us.net>
The endpoint library must be initialized before its users, which are in
drivers/pci/controllers. The endpoint initialization currently depends on
link order.
This corrects a kernel crash when loading the Cadence EP driver, since it
calls devm_pci_epc_create() and this is only valid once the endpoint
library has been initialized.
Fixes: 6e0832fa432e ("PCI: Collect all native drivers under drivers/pci/controller/")
Signed-off-by: Alan Douglas <adouglas@cadence.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
An SHPC can be operated either by platform firmware or by the OS. The OS
uses a host bridge ACPI _OSC method to negotiate for control of SHPC. If
firmware wants to prevent an OS from operating an SHPC, it must supply an
_OSC method that declines to grant SHPC ownership to the OS.
If acpi_pci_find_root() returns NULL, it means there's no ACPI host bridge
device (PNP0A03 or PNP0A08) and hence no _OSC method, so the OS is always
allowed to manage the SHPC.
Fix a NULL pointer dereference when CONFIG_ACPI=y but the current
hardware/firmware platform doesn't support ACPI. In that case,
acpi_get_hp_hw_control_from_firmware() is implemented but
acpi_pci_find_root() returns NULL.
Fixes: 90cc0c3cc709 ("PCI: shpchp: Add shpchp_is_native()")
Link: https://lkml.kernel.org/r/20180621164715.28160-1-marc.zyngier@arm.com
Reported-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Pull block fixes from Jens Axboe:
"A collection of fixes that should go into -rc1. This contains:
- bsg_open vs bsg_unregister race fix (Anatoliy)
- NVMe pull request from Christoph, with fixes for regressions in
this window, FC connect/reconnect path code unification, and a
trace point addition.
- timeout fix (Christoph)
- remove a few unused functions (Christoph)
- blk-mq tag_set reinit fix (Roman)"
* tag 'for-linus-20180616' of git://git.kernel.dk/linux-block:
bsg: fix race of bsg_open and bsg_unregister
block: remov blk_queue_invalidate_tags
nvme-fabrics: fix and refine state checks in __nvmf_check_ready
nvme-fabrics: handle the admin-only case properly in nvmf_check_ready
nvme-fabrics: refactor queue ready check
blk-mq: remove blk_mq_tagset_iter
nvme: remove nvme_reinit_tagset
nvme-fc: fix nulling of queue data on reconnect
nvme-fc: remove reinit_request routine
blk-mq: don't time out requests again that are in the timeout handler
nvme-fc: change controllers first connect to use reconnect path
nvme: don't rely on the changed namespace list log
nvmet: free smart-log buffer after use
nvme-rdma: fix error flow during mapping request data
nvme: add bio remapping tracepoint
nvme: fix NULL pointer dereference in nvme_init_subsystem
blk-mq: reinit q->tag_set_list entry only after grace period
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