linux-stable.git/drivers/pci/hotplug/pnv_php.c, branch linux-6.10.y Linux kernel stable tree pci/hotplug/pnv_php: Fix hotplug driver crash on Powernv 2024-09-12T09:12:59+00:00 Krishna Kumar krishnak@linux.ibm.com 2024-07-01T07:45:06+00:00 bfc44075b19740d372f989f21dd03168bfda0689 [ Upstream commit 335e35b748527f0c06ded9eebb65387f60647fda ] The hotplug driver for powerpc (pci/hotplug/pnv_php.c) causes a kernel crash when we try to hot-unplug/disable the PCIe switch/bridge from the PHB. The crash occurs because although the MSI data structure has been released during disable/hot-unplug path and it has been assigned with NULL, still during unregistration the code was again trying to explicitly disable the MSI which causes the NULL pointer dereference and kernel crash. The patch fixes the check during unregistration path to prevent invoking pci_disable_msi/msix() since its data structure is already freed. Reported-by: Timothy Pearson <tpearson@raptorengineering.com> Closes: https://lore.kernel.org/all/1981605666.2142272.1703742465927.JavaMail.zimbra@raptorengineeringinc.com/ Acked-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Shawn Anastasio <sanastasio@raptorengineering.com> Signed-off-by: Krishna Kumar <krishnak@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240701074513.94873-2-krishnak@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 335e35b748527f0c06ded9eebb65387f60647fda ]

The hotplug driver for powerpc (pci/hotplug/pnv_php.c) causes a kernel
crash when we try to hot-unplug/disable the PCIe switch/bridge from
the PHB.

The crash occurs because although the MSI data structure has been
released during disable/hot-unplug path and it has been assigned
with NULL, still during unregistration the code was again trying to
explicitly disable the MSI which causes the NULL pointer dereference and
kernel crash.

The patch fixes the check during unregistration path to prevent invoking
pci_disable_msi/msix() since its data structure is already freed.

Reported-by: Timothy Pearson <tpearson@raptorengineering.com>
Closes: https://lore.kernel.org/all/1981605666.2142272.1703742465927.JavaMail.zimbra@raptorengineeringinc.com/
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Shawn Anastasio <sanastasio@raptorengineering.com>
Signed-off-by: Krishna Kumar <krishnak@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240701074513.94873-2-krishnak@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
PCI: hotplug: Use FIELD_GET/PREP() 2023-10-24T15:54:04+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2023-10-18T11:32:50+00:00 abaaac4845a0d6f39f83cbaba4c3b46ba5f93170 Instead of handcrafted shifts to handle register fields, use FIELD_GET/FIELD_PREP(). Link: https://lore.kernel.org/r/20231018113254.17616-4-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> 
Instead of handcrafted shifts to handle register fields, use
FIELD_GET/FIELD_PREP().

Link: https://lore.kernel.org/r/20231018113254.17616-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
PCI: hotplug: Clean up include files 2022-04-05T16:13:33+00:00 Christophe Leroy christophe.leroy@csgroup.eu 2022-04-02T10:11:56+00:00 b2851926c6d9d977ff60f613aff95f4900b9620e arch/powerpc/include/asm/prom.h includes some headers that it doesn't need itself. Add the missing headers to files that include prom.h so we can remove them from prom.h. Link: https://lore.kernel.org/r/79201f5fae8d003164ac36ed3be7789db1bc5ab4.1648833421.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> 
arch/powerpc/include/asm/prom.h includes some headers that it doesn't need
itself.  Add the missing headers to files that include prom.h so we can
remove them from prom.h.

Link: https://lore.kernel.org/r/79201f5fae8d003164ac36ed3be7789db1bc5ab4.1648833421.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
PCI: Change the type of probe argument in reset functions 2021-08-18T22:32:42+00:00 Amey Narkhede ameynarkhede03@gmail.com 2021-08-17T18:05:00+00:00 9bdc81ce440ec6ea899b236879aee470ec388020 Change the type of probe argument in functions which implement reset methods from int to bool to make the context and intent clear. Suggested-by: Alex Williamson <alex.williamson@redhat.com> Link: https://lore.kernel.org/r/20210817180500.1253-10-ameynarkhede03@gmail.com Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> 
Change the type of probe argument in functions which implement reset
methods from int to bool to make the context and intent clear.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20210817180500.1253-10-ameynarkhede03@gmail.com
Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
pci/hotplug/pnv-php: Wrap warnings in macro 2020-01-23T10:31:17+00:00 Frederic Barrat fbarrat@linux.ibm.com 2019-11-21T13:49:17+00:00 748ac391ab9acd8d7f3c93cbf3e63c773c0b2638 An opencapi slot doesn't have an associated bridge device. It's not needed for operation, but any warning is displayed through pci_warn() which uses the pci_dev struct of the assocated bridge device. So wrap those warning so that a different trace mechanism can be used if it's an opencapi slot. Reviewed-by: Alastair D'Silva <alastair@d-silva.org> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191121134918.7155-11-fbarrat@linux.ibm.com 
An opencapi slot doesn't have an associated bridge device. It's not
needed for operation, but any warning is displayed through pci_warn()
which uses the pci_dev struct of the assocated bridge device. So wrap
those warning so that a different trace mechanism can be used if it's
an opencapi slot.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-11-fbarrat@linux.ibm.com
pci/hotplug/pnv-php: Relax check when disabling slot 2020-01-23T10:31:17+00:00 Frederic Barrat fbarrat@linux.ibm.com 2019-11-21T13:49:16+00:00 be1611e043de63948c21cc7dd27ea6798ffd6fa4 The driver only allows to disable a slot in the POPULATED state. However, if an error occurs while enabling the slot, say because the link couldn't be trained, then the POPULATED state may not be reached, yet the power state of the slot is on. So allow to disable a slot in the REGISTERED state. Removing the devices will do nothing since it's not populated, and we'll set the power state of the slot back to off. Reviewed-by: Alastair D'Silva <alastair@d-silva.org> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191121134918.7155-10-fbarrat@linux.ibm.com 
The driver only allows to disable a slot in the POPULATED
state. However, if an error occurs while enabling the slot, say
because the link couldn't be trained, then the POPULATED state may not
be reached, yet the power state of the slot is on. So allow to disable
a slot in the REGISTERED state. Removing the devices will do nothing
since it's not populated, and we'll set the power state of the slot
back to off.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-10-fbarrat@linux.ibm.com
pci/hotplug/pnv-php: Register opencapi slots 2020-01-23T10:31:17+00:00 Frederic Barrat fbarrat@linux.ibm.com 2019-11-21T13:49:15+00:00 ea53919b15bf1e821b034b9c89758008de521437 Add the opencapi PHBs to the list of PHBs being scanned to look for slots. Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191121134918.7155-9-fbarrat@linux.ibm.com 
Add the opencapi PHBs to the list of PHBs being scanned to look for
slots.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-9-fbarrat@linux.ibm.com
pci/hotplug/pnv-php: Improve error msg on power state change failure 2020-01-23T10:31:17+00:00 Frederic Barrat fbarrat@linux.ibm.com 2019-11-21T13:49:14+00:00 323c2a26ff43500a96799250330fab68903d776f When changing the slot state, if opal hits an error and tells as such in the asynchronous reply, the warning "Wrong msg" is logged, which is rather confusing. Instead we can reuse the better message which is already used when we couldn't submit the asynchronous opal request initially. Reviewed-by: Alastair D'Silva <alastair@d-silva.org> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191121134918.7155-8-fbarrat@linux.ibm.com 
When changing the slot state, if opal hits an error and tells as such
in the asynchronous reply, the warning "Wrong msg" is logged, which is
rather confusing. Instead we can reuse the better message which is
already used when we couldn't submit the asynchronous opal request
initially.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-8-fbarrat@linux.ibm.com
pci/hotplug/pnv-php: Remove erroneous warning 2020-01-23T10:31:17+00:00 Frederic Barrat fbarrat@linux.ibm.com 2019-11-21T13:49:13+00:00 658ab186dd22060408d94f5c5a6d02d809baba44 On powernv, when removing a device through hotplug, the following warning is logged: Invalid refcount <.> on <...> It may be incorrect, the refcount may be set to a higher value than 1 and be valid. of_detach_node() can drop more than one reference. As it doesn't seem trivial to assert the correct value, let's remove the warning. Reviewed-by: Alastair D'Silva <alastair@d-silva.org> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191121134918.7155-7-fbarrat@linux.ibm.com 
On powernv, when removing a device through hotplug, the following
warning is logged:

     Invalid refcount <.> on <...>

It may be incorrect, the refcount may be set to a higher value than 1
and be valid. of_detach_node() can drop more than one reference. As it
doesn't seem trivial to assert the correct value, let's remove the
warning.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-7-fbarrat@linux.ibm.com
pci-hotplug/pnv_php: Add attention indicator support 2019-09-05T04:22:39+00:00 Oliver O'Halloran oohall@gmail.com 2019-09-03T10:16:01+00:00 018c49e999ac4680e59de236a4a8cde209e8cc98 pnv_php is generally used with PCIe bridges which provide a native interface for setting the attention and power indicator LEDs. Wire up those interfaces even if firmware does not have support for them (yet...) Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-11-oohall@gmail.com 
pnv_php is generally used with PCIe bridges which provide a native
interface for setting the attention and power indicator LEDs. Wire up
those interfaces even if firmware does not have support for them (yet...)

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903101605.2890-11-oohall@gmail.com