kernel/linux.git/drivers/misc/ocxl, branch v5.9.2

ocxl: fix kconfig dependency warning for OCXL

2020-10-29T09:11:33+00:00

[ Upstream commit 4b53a3c72116118d86fab4112277e1dc4edf273c ] When OCXL is enabled and HOTPLUG_PCI is disabled, it results in the following Kbuild warning: WARNING: unmet direct dependencies detected for HOTPLUG_PCI_POWERNV Depends on [n]: PCI [=y] && HOTPLUG_PCI [=n] && PPC_POWERNV [=y] && EEH [=y] Selected by [y]: - OCXL [=y] && PPC_POWERNV [=y] && PCI [=y] && EEH [=y] The reason is that OCXL selects HOTPLUG_PCI_POWERNV without depending on or selecting HOTPLUG_PCI while HOTPLUG_PCI_POWERNV is subordinate to HOTPLUG_PCI. HOTPLUG_PCI_POWERNV is a visible symbol with a set of dependencies. Selecting it will lead to overlooking its other dependencies as well. Let OCXL depend on HOTPLUG_PCI_POWERNV instead to avoid Kbuild issues. Fixes: 49ce94b8677c ("ocxl: Add PCI hotplug dependency to Kconfig") Acked-by: Frederic Barrat Signed-off-by: Necip Fazil Yildiran Link: https://lore.kernel.org/r/20200918094148.20525-1-fazilyildiran@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

ocxl: Address kernel doc errors & warnings

2020-07-29T13:47:52+00:00

This patch addresses warnings and errors from the kernel doc scripts for the OpenCAPI driver. It also makes minor tweaks to make the docs more consistent. Signed-off-by: Alastair D'Silva Acked-by: Andrew Donnellan Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200415012343.919255-3-alastair@d-silva.org

ocxl: Replace HTTP links with HTTPS ones

2020-07-16T03:12:46+00:00

Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov Acked-by: Andrew Donnellan Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200713175506.36676-1-grandmaster@al2klimov.de

ocxl: control via sysfs whether the FPGA is reloaded on a link reset

2020-07-15T01:07:19+00:00

Some opencapi FPGA images allow to control if the FPGA should be reloaded on the next adapter reset. If it is supported, the image specifies it through a Vendor Specific DVSEC in the config space of function 0. Signed-off-by: Philippe Bergheaud Signed-off-by: Frederic Barrat Reviewed-by: Andrew Donnellan Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200619140439.153962-1-fbarrat@linux.ibm.com

ocxl: Fix misleading comment

2020-05-20T13:39:57+00:00

In ocxl_context_free() we note that the AFU reference we're releasing was taken in "ocxl_context_init", a function that no longer exists. Fix it to say ocxl_context_alloc() instead, which is the new name for ocxl_context_init(), since it was renamed. Fixes: b9721d275cc2 ("ocxl: Allow external drivers to use OpenCAPI contexts") Signed-off-by: Andrew Donnellan Acked-by: Frederic Barrat Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200226043923.5481-1-ajd@linux.ibm.com

ocxl: Add PCI hotplug dependency to Kconfig

2020-01-23T10:31:18+00:00

The PCI hotplug framework is used to update the devices when a new image is written to the FPGA. Reviewed-by: Alastair D'Silva Reviewed-by: Andrew Donnellan Signed-off-by: Frederic Barrat Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191121134918.7155-12-fbarrat@linux.ibm.com

ocxl: Fix potential memory leak on context creation

2019-12-13T20:59:39+00:00

If we couldn't fully init a context, we were leaking memory. Fixes: b9721d275cc2 ("ocxl: Allow external drivers to use OpenCAPI contexts") Signed-off-by: Frederic Barrat Acked-by: Andrew Donnellan Reviewed-by: Greg Kurz Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191209105513.8566-1-fbarrat@linux.ibm.com

ocxl: Fix concurrent AFU open and device removal

2019-12-10T09:34:23+00:00

If an ocxl device is unbound through sysfs at the same time its AFU is being opened by a user process, the open code may dereference freed stuctures, which can lead to kernel oops messages. You'd have to hit a tiny time window, but it's possible. It's fairly easy to test by making the time window bigger artificially. Fix it with a combination of 2 changes: - when an AFU device is found in the IDR by looking for the device minor number, we should hold a reference on the device until after the context is allocated. A reference on the AFU structure is kept when the context is allocated, so we can release the reference on the device after the context allocation. - with the fix above, there's still another even tinier window, between the time the AFU device is found in the IDR and the reference on the device is taken. We can fix this one by removing the IDR entry earlier, when the device setup is removed, instead of waiting for the 'release' device callback. With proper locking around the IDR. Fixes: 75ca758adbaf ("ocxl: Create a clear delineation between ocxl backend & frontend") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Frederic Barrat Reviewed-by: Greg Kurz Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190624144148.32022-1-fbarrat@linux.ibm.com

ocxl: Use the correct style for SPDX License Identifier

2019-10-10T13:34:40+00:00

This patch corrects the SPDX License Identifier style in header files for Open Coherent Accelerator (OCXL) compatible device drivers. For C header files Documentation/process/license-rules.rst mandates C-like comments (opposed to C source files where C++ style should be used) Changes made by using a script provided by Joe Perches here: https://lkml.org/lkml/2019/2/7/46. Suggested-by: Joe Perches Signed-off-by: Nishad Kamdar Acked-by: Andrew Donnellan Link: https://lore.kernel.org/r/20190920161826.GA6894@nishad Signed-off-by: Greg Kroah-Hartman

powerpc/64s/radix: introduce options to disable use of the tlbie instruction

2019-09-05T04:22:41+00:00

Introduce two options to control the use of the tlbie instruction. A boot time option which completely disables the kernel using the instruction, this is currently incompatible with HASH MMU, KVM, and coherent accelerators. And a debugfs option can be switched at runtime and avoids using tlbie for invalidating CPU TLBs for normal process and kernel address mappings. Coherent accelerators are still managed with tlbie, as will KVM partition scope translations. Cross-CPU TLB flushing is implemented with IPIs and tlbiel. This is a basic implementation which does not attempt to make any optimisation beyond the tlbie implementation. This is useful for performance testing among other things. For example in certain situations on large systems, using IPIs may be faster than tlbie as they can be directed rather than broadcast. Later we may also take advantage of the IPIs to do more interesting things such as trim the mm cpumask more aggressively. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190902152931.17840-7-npiggin@gmail.com