linux-stable.git/drivers/pci, branch v4.19.26

PCI: Fix __initdata issue with "pci=disable_acs_redir" parameter

2019-02-23T08:07:26+00:00

commit d2fd6e81912a665993b24dcdc1c1384a42a54f7e upstream.

The disable_acs_redir parameter stores a pointer to the string passed to
pci_setup().  However, the string passed to PCI setup is actually a
temporary copy allocated in static __initdata memory.  After init, once the
memory is freed, it is no longer valid to reference this pointer.

This bug was noticed in v5.0-rc1 after a change in commit c5eb1190074c
("PCI / PM: Allow runtime PM without callback functions") caused
pci_disable_acs_redir() to be called during shutdown which manifested
as an unable to handle kernel paging request at:

  RIP: 0010:pci_enable_acs+0x3f/0x1e0
  Call Trace:
     pci_restore_state.part.44+0x159/0x3c0
     pci_restore_standard_config+0x33/0x40
     pci_pm_runtime_resume+0x2b/0xd0
     ? pci_restore_standard_config+0x40/0x40
     __rpm_callback+0xbc/0x1b0
     rpm_callback+0x1f/0x70
     ? pci_restore_standard_config+0x40/0x40
      rpm_resume+0x4f9/0x710
     ? pci_conf1_read+0xb6/0xf0
     ? pci_conf1_write+0xb2/0xe0
     __pm_runtime_resume+0x47/0x70
     pci_device_shutdown+0x1e/0x60
     device_shutdown+0x14a/0x1f0
     kernel_restart+0xe/0x50
     __do_sys_reboot+0x1ee/0x210
     ? __fput+0x144/0x1d0
     do_writev+0x5e/0xf0
     ? do_writev+0x5e/0xf0
     do_syscall_64+0x48/0xf0
     entry_SYSCALL_64_after_hwframe+0x44/0xa9

It was also likely possible to trigger this bug when hotplugging PCI
devices.

To fix this, instead of storing a pointer, we use kstrdup() to copy the
disable_acs_redir_param to its own buffer which will never be freed.

Fixes: aaca43fda742 ("PCI: Add "pci=disable_acs_redir=" parameter for peer-to-peer support")
Tested-by: Jarkko Nikula 
Signed-off-by: Logan Gunthorpe 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Jarkko Nikula 
Signed-off-by: Greg Kroah-Hartman

PCI: imx: Enable MSI from downstream components

2019-02-12T18:47:19+00:00

[ Upstream commit 75cb8d20c112aba70f23d98e3f8d0a38ace16006 ]

The MSI Enable bit in the MSI Capability (PCIe r4.0, sec 7.7.1.2) controls
whether a Function can request service using MSI.

i.MX6 Root Ports implement the MSI Capability and may use MSI to request
service for events like PME, hotplug, AER, etc.  In addition, on i.MX6, the
MSI Enable bit controls delivery of MSI interrupts from components below
the Root Port.

Prior to f3fdfc4ac3a2 ("PCI: Remove host driver Kconfig selection of
CONFIG_PCIEPORTBUS"), enabling CONFIG_PCI_IMX6 automatically also enabled
CONFIG_PCIEPORTBUS, and when portdrv claimed the Root Ports, it set the MSI
Enable bit so it could use PME, hotplug, AER, etc.  As a side effect, that
also enabled delivery of MSI interrupts from downstream components.

The imx6q-pcie driver itself does not depend on portdrv, so set MSI Enable
in imx6q-pcie so MSI from downstream components works even if nobody uses
MSI for the Root Port events.

Fixes: f3fdfc4ac3a2 ("PCI: Remove host driver Kconfig selection of CONFIG_PCIEPORTBUS")
Signed-off-by: Richard Zhu 
Signed-off-by: Bjorn Helgaas 
Tested-by: Sven Van Asbroeck 
Tested-by: Trent Piepho 
Reviewed-by: Lucas Stach 
Acked-by: Lorenzo Pieralisi 
Signed-off-by: Sasha Levin

switchtec: Fix SWITCHTEC_IOCTL_EVENT_IDX_ALL flags overwrite

2019-02-12T18:47:09+00:00

[ Upstream commit e4a7dca5de625018b29417ecc39dc5037d9a5a36 ]

In the ioctl_event_ctl() SWITCHTEC_IOCTL_EVENT_IDX_ALL case, we call
event_ctl() several times with the same "ctl" struct.  Each call clobbers
ctl.flags, which leads to the problem that we may not actually enable or
disable all events as the user requested.

Preserve the event flag value with a temporary variable.

Fixes: 52eabba5bcdb ("switchtec: Add IOCTLs to the Switchtec driver")
Signed-off-by: Joey Zhang 
Signed-off-by: Wesley Sheng 
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Logan Gunthorpe 
Signed-off-by: Sasha Levin

PCI: dwc: Move interrupt acking into the proper callback

2019-01-16T21:04:35+00:00

commit 3f7bb2ec20ce07c02b2002349d256c91a463fcc5 upstream.

The write to the status register is really an ACK for the HW,
and should be treated as such by the driver. Let's move it to the
irq_ack() callback, which will prevent people from moving it around
in order to paper over other bugs.

Fixes: 8c934095fa2f ("PCI: dwc: Clear MSI interrupt status after it is handled,
not before")
Fixes: 7c5925afbc58 ("PCI: dwc: Move MSI IRQs allocation to IRQ domains
hierarchical API")
Link: https://lore.kernel.org/linux-pci/20181113225734.8026-1-marc.zyngier@arm.com/
Reported-by: Trent Piepho 
Tested-by: Niklas Cassel 
Tested-by: Gustavo Pimentel 
Tested-by: Stanimir Varbanov 
Signed-off-by: Marc Zyngier 
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

PCI: dwc: Take lock when ACKing an interrupt

2019-01-16T21:04:34+00:00

commit fce5423e4f431c71933d6c1f850b540a314aa6ee upstream.

Bizarrely, there is no lock taken in the irq_ack() helper. This
puts the ACK callback provided by a specific platform in a awkward
situation where there is no synchronization that would be expected
on other callback.

Introduce the required lock, giving some level of uniformity among
callbacks.

Fixes: 7c5925afbc58 ("PCI: dwc: Move MSI IRQs allocation to IRQ domains
hierarchical API")
Link: https://lore.kernel.org/linux-pci/20181113225734.8026-1-marc.zyngier@arm.com/
Tested-by: Niklas Cassel 
Tested-by: Gustavo Pimentel 
Tested-by: Stanimir Varbanov 
Signed-off-by: Marc Zyngier 
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

PCI: dwc: Use interrupt masking instead of disabling

2019-01-16T21:04:34+00:00

commit 830920e065e90db318a0da98bf13a02b641eae7f upstream.

The dwc driver is showing an interesting level of brokeness, as it
insists on using the enable/disable set of registers to mask/unmask
MSIs, meaning that an MSIs being generated while the interrupt is in
that "disabled" state will simply be lost.

Let's move to the mask/unmask set of registers, which offers the
expected semantics.

Fixes: 7c5925afbc58 ("PCI: dwc: Move MSI IRQs allocation to IRQ domains
hierarchical API")
Link: https://lore.kernel.org/linux-pci/20181113225734.8026-1-marc.zyngier@arm.com/
Tested-by: Niklas Cassel 
Tested-by: Gustavo Pimentel 
Tested-by: Stanimir Varbanov 
Signed-off-by: Marc Zyngier 
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

PCI / PM: Allow runtime PM without callback functions

2019-01-13T08:51:07+00:00

commit c5eb1190074cfb14c5d9cac692f1912eecf1a5e4 upstream.

a9c8088c7988 ("i2c: i801: Don't restore config registers on runtime PM")
nullified the runtime PM suspend/resume callback pointers while keeping the
runtime PM enabled.

This caused the SMBus PCI device to stay in D0 with
/sys/devices/.../power/runtime_status showing "error" when the runtime PM
framework attempted to autosuspend the device.  This is due to PCI bus
runtime PM, which checks for driver runtime PM callbacks and returns
-ENOSYS if they are not set.

Since i2c-i801.c doesn't need to do anything device-specific for runtime
PM, Jean Delvare proposed this be fixed in the PCI core rather than adding
dummy runtime PM callback functions in the PCI drivers.

Change pci_pm_runtime_suspend()/pci_pm_runtime_resume() so they allow
changing the PCI device power state during runtime PM transitions even if
the driver supplies no runtime PM callbacks.

This fixes the runtime PM regression on i2c-i801.c.

It is not obvious why the code previously required the runtime PM
callbacks.  The test has been there since the code was introduced by
6cbf82148ff2 ("PCI PM: Run-time callbacks for PCI bus type").

On the other hand, a similar change was done to generic runtime PM
callbacks in 05aa55dddb9e ("PM / Runtime: Lenient generic runtime pm
callbacks").

Fixes: a9c8088c7988 ("i2c: i801: Don't restore config registers on runtime PM")
Reported-by: Mika Westerberg 
Signed-off-by: Jarkko Nikula 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Jean Delvare 
Reviewed-by: Rafael J. Wysocki 
Cc: stable@vger.kernel.org	# v4.18+
Signed-off-by: Greg Kroah-Hartman

PCI: imx6: Fix link training status detection in link up check

2018-12-17T08:24:33+00:00

[ Upstream commit 68bc10bf992180f269816ff3d22eb30383138577 ]

This bug was introduced in the interaction for two commits on either
branch of the merge commit 562df5c8521e ("Merge branch
'pci/host-designware' into next").

Commit 4d107d3b5a68 ("PCI: imx6: Move link up check into
imx6_pcie_wait_for_link()"), changed imx6_pcie_wait_for_link() to poll
the link status register directly, checking for link up and not
training, and made imx6_pcie_link_up() only check the link up bit (once,
not a polling loop).

While commit 886bc5ceb5cc ("PCI: designware: Add generic
dw_pcie_wait_for_link()"), replaced the loop in
imx6_pcie_wait_for_link() with a call to a new dwc core function, which
polled imx6_pcie_link_up(), which still checked both link up and not
training in a loop.

When these two commits were merged, the version of
imx6_pcie_wait_for_link() from 886bc5ceb5cc was kept, which eliminated
the link training check placed there by 4d107d3b5a68. However, the
version of imx6_pcie_link_up() from 4d107d3b5a68 was kept, which
eliminated the link training check that had been there and was moved to
imx6_pcie_wait_for_link().

The result was the link training check got lost for the imx6 driver.

Eliminate imx6_pcie_link_up() so that the default handler,
dw_pcie_link_up(), is used instead. The default handler has the correct
code, which checks for link up and also that it still is not training,
fixing the regression.

Fixes: 562df5c8521e ("Merge branch 'pci/host-designware' into next")
Signed-off-by: Trent Piepho 
[lorenzo.pieralisi@arm.com: rewrote the commit log]
Signed-off-by: Lorenzo Pieralisi 
Reviewed-by: Lucas Stach 
Cc: Bjorn Helgaas 
Cc: Joao Pinto 
Cc: Lorenzo Pieralisi 
Cc: Richard Zhu 
Signed-off-by: Sasha Levin

PCI: Fix incorrect value returned from pcie_get_speed_cap()

2018-12-05T18:32:07+00:00

commit f1f90e254e46e0a14220e4090041f68256fbe297 upstream.

The macros PCI_EXP_LNKCAP_SLS_*GB are values, not bit masks.  We must mask
the register and compare it against them.

This fixes errors like this:

  amdgpu: [powerplay] failed to send message 261 ret is 0

when a PCIe-v3 card is plugged into a PCIe-v1 slot, because the slot is
being incorrectly reported as PCIe-v3 capable.

6cf57be0f78e, which appeared in v4.17, added pcie_get_speed_cap() with the
incorrect test of PCI_EXP_LNKCAP_SLS as a bitmask.  5d9a63304032, which
appeared in v4.19, changed amdgpu to use pcie_get_speed_cap(), so the
amdgpu bug reports below are regressions in v4.19.

Fixes: 6cf57be0f78e ("PCI: Add pcie_get_speed_cap() to find max supported link speed")
Fixes: 5d9a63304032 ("drm/amdgpu: use pcie functions for link width and speed")
Link: https://bugs.freedesktop.org/show_bug.cgi?id=108704
Link: https://bugs.freedesktop.org/show_bug.cgi?id=108778
Signed-off-by: Mikulas Patocka 
[bhelgaas: update comment, remove use of PCI_EXP_LNKCAP_SLS_8_0GB and
PCI_EXP_LNKCAP_SLS_16_0GB since those should be covered by PCI_EXP_LNKCAP2,
remove test of PCI_EXP_LNKCAP for zero, since that register is required]
Signed-off-by: Bjorn Helgaas 
Acked-by: Alex Deucher 
Cc: stable@vger.kernel.org	# v4.17+
Signed-off-by: Greg Kroah-Hartman

PCI: dwc: Fix MSI-X EP framework address calculation bug

2018-12-05T18:32:07+00:00

commit 15cb127e3c8f6232096d5dba6a5b4046bc292d70 upstream.

Fix an error caused by 3-bit right rotation on offset address
calculation of MSI-X table in dw_pcie_ep_raise_msix_irq().

The initial testing code was setting by default the offset address of
MSI-X table to zero, so that even with a 3-bit right rotation the
computed result would still be zero and valid, therefore this bug went
unnoticed.

Fixes: beb4641a787d ("PCI: dwc: Add MSI-X callbacks handler")
Signed-off-by: Gustavo Pimentel 
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman