kernel/linux.git/drivers/misc/cxl, branch linux-4.3.y

cxl: Fix number of allocated pages in SPA

2015-10-07T05:44:46+00:00

The scheduled process area is currently allocated before assigning the correct maximum processes to the AFU, which will mean we only ever allocate a fixed number of pages for the scheduled process area. This will limit us to 958 processes with 2 x 64K pages. If we try to use more processes than that we'd probably overrun the buffer and corrupt memory or crash. AFUs that require three or more interrupts per process will not be affected as they are already limited to less processes than that, but we could hit it on an AFU that requires 0, 1 or 2 interrupts per process, or when using 4K pages. This patch moves the initialisation of the num_procs to before the SPA allocation so that enough pages will be allocated for the number of processes that the AFU supports. Signed-off-by: Christophe Lombard Signed-off-by: Ian Munsie Cc: # 3.18+ Signed-off-by: Michael Ellerman

cxl: Workaround malformed pcie packets on some cards

2015-10-06T09:59:46+00:00

This works around a pcie host bridge defect on some cards, that can cause malformed Transaction Layer Packet (TLP) errors to be erroneously reported. The upper nibble of the vendor section PSL revision is used to distinguish between different cards. The affected ones have it set to 0. Signed-off-by: Philippe Bergheaud Acked-by: Ian Munsie Signed-off-by: Michael Ellerman

cxl: fix leak of ctx->mapping when releasing kernel API contexts

2015-10-01T01:50:12+00:00

When a context is created via the kernel API, ctx->mapping is allocated within the kernel and thus needs to be freed when the context is freed. reclaim_ctx() attempts to do this for contexts with the ctx->kernelapi flag set, but afu_release() (which can be called from the kernel API through cxl_fd_release()) sets ctx->mapping to NULL before calling cxl_context_free() to free the context. Add a check to afu_release() so that the mappings in contexts created via the kernel API are left alone so reclaim_ctx() can free them. Reported-by: Matthew R. Ochs Fixes: 6f7f0b3df6d4 ("cxl: Add AFU virtual PHB and kernel API") Signed-off-by: Andrew Donnellan Acked-by: Ian Munsie Reviewed-by: Matthew R. Ochs Signed-off-by: Michael Ellerman

cxl: fix leak of ctx->irq_bitmap when releasing context via kernel API

2015-10-01T01:49:32+00:00

At present, ctx->irq_bitmap is freed in afu_release_irqs(), which is called from afu_release() via cxl_context_detach(). Move the freeing of ctx->irq_bitmap from afu_release_irqs() to reclaim_ctx() (called through cxl_context_free()) so it's freed when releasing a context via the kernel API (cxl_release_context()) or the userspace API (afu_release()). Reported-by: Matthew R. Ochs Fixes: 6f7f0b3df6d4 ("cxl: Add AFU virtual PHB and kernel API") Signed-off-by: Andrew Donnellan Acked-by: Ian Munsie Reviewed-by: Matthew R. Ochs Signed-off-by: Michael Ellerman

cxl: fix leak of IRQ names in cxl_free_afu_irqs()

2015-10-01T01:49:32+00:00

cxl_free_afu_irqs() doesn't free IRQ names when it releases an AFU's IRQ ranges. The userspace API equivalent in afu_release_irqs() calls afu_irq_name_free() to release the IRQ names. Call afu_irq_name_free() in cxl_free_afu_irqs() to release the IRQ names. Make afu_irq_name_free() non-static to allow this. Reported-by: Matthew R. Ochs Fixes: 6f7f0b3df6d4 ("cxl: Add AFU virtual PHB and kernel API") Signed-off-by: Andrew Donnellan Signed-off-by: Ian Munsie Reviewed-by: Matthew R. Ochs Signed-off-by: Michael Ellerman

cxl: Fix lockdep warning while creating afu_err_buff attribute

2015-09-23T10:57:13+00:00

Presently a lockdep warning is reported during creation of afu_err_buff bin_attribute for the afu. This is caused due to the variable attr.key not pointing to a static class key, hence the function lockdep_init_map reports this warning: BUG: key not in .data! The patch fixes this issue by calling sysfs_attr_init on the attr_eb.attr structure before populating it with the afu_err_buff file details. This will populate the attr.key variable with a static class key so that lockdep_init_map stops complaining about the lockdep key not being static. Reported-by: Daniel Axtens Signed-off-by: Vaibhav Jain Acked-by: Ian Munsie Reviewed-by: Daniel Axtens Signed-off-by: Michael Ellerman

cxl: Fix build failure due to -Wunused-variable behaviour change

2015-09-15T09:33:51+00:00

A recent change in gcc caused this build failure: /var/lib/jenkins/workspace/gcc_kernel_build/linux/drivers/misc/cxl/cxl.h:72:27: error: ‘CXL_PSL_DLCNTL’ defined but not used [-Werror=unused-const-variable] static const cxl_p1_reg_t CXL_PSL_DLCNTL = {0x0060}; Because of this gcc commit: Commit 1bca8cbd0c68366f07277f98ce6963e10c2aa617 by mark PR28901 -Wunused-variable ignores unused const initialised variables in C 12 years ago it was decided that -Wunused-variable shouldn't warn about static const variables because some code used const static char rcsid[] strings which were never used but wanted in the code anyway. But as the bug points out this hides some real bugs. These days the usage of rcsids is not very popular anymore. So this patch changes the default to warn about unused static const variables in C with -Wunused-variable. And it adds a new option -Wno-unused-const-variable to turn this warning off. For C++ this new warning is off by default, since const variables can be used as #defines in C++. New testcases for the new defaults in C and C++ are included testing the new warning and suppressing it with an unused attribute or using -Wno-unused-const-variable. gcc/ChangeLog The cxl driver uses static consts in place of #defines in some cases for type safety, so this change causes the driver to fail to build on new copilers as these constants are not all used in every file that imports the header. Suppress the warning for this driver to return to the old behaviour of -Wunused-variable. Reported-by: Anton Blanchard Signed-off-by: Ian Munsie Signed-off-by: Michael Ellerman

cxl: Fix unbalanced pci_dev_get in cxl_probe

2015-09-15T09:33:38+00:00

Currently the first thing we do in cxl_probe is to grab a reference on the pci device. Later on, we call device_register on our adapter. In our remove path, we call device_unregister, but we never call pci_dev_put. We therefore leak the device every time we do a reflash. device_register/unregister is sufficient to hold the reference. Therefore, drop the call to pci_dev_get. Here's why this is safe. The proposed cxl_probe(pdev) calls cxl_adapter_init: a) init calls cxl_adapter_alloc, which creates a struct cxl, conventionally called adapter. This struct contains a device entry, adapter->dev. b) init calls cxl_configure_adapter, where we set adapter->dev.parent = &dev->dev (here dev is the pci dev) So at this point, the cxl adapter's device's parent is the PCI device that I want to be refcounted properly. c) init calls cxl_register_adapter *) cxl_register_adapter calls device_register(&adapter->dev) So now we're in device_register, where dev is the adapter device, and we want to know if the PCI device is safe after we return. device_register(&adapter->dev) calls device_initialize() and then device_add(). device_add() does a get_device(). device_add() also explicitly grabs the device's parent, and calls get_device() on it: parent = get_device(dev->parent); So therefore, device_register() takes a lock on the parent PCI dev, which is what pci_dev_get() was guarding. pci_dev_get() can therefore be safely removed. Fixes: f204e0b8cedd ("cxl: Driver code for powernv PCIe based cards for userspace access") Cc: stable@vger.kernel.org Signed-off-by: Daniel Axtens Acked-by: Ian Munsie Signed-off-by: Michael Ellerman

cxl: abort cxl_pci_enable_device_hook() if PCI channel is offline

2015-09-07T10:14:24+00:00

cxl_pci_enable_device_hook() is called when attempting to enable an AFU sitting on a vPHB. At present, the state of the underlying CXL card's PCI channel is only checked when it calls cxl_afu_check_and_enable() at the very end, after it has already set DMA options and initialised a default context. Check the CXL card's link status before setting DMA options or initialising a default context. If the link is down, print a warning and return immediately. Signed-off-by: Andrew Donnellan Acked-by: Ian Munsie Signed-off-by: Michael Ellerman

Merge tag 'powerpc-4.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2015-09-03T23:41:38+00:00

Pull powerpc updates from Michael Ellerman: - support "hybrid" iommu/direct DMA ops for coherent_mask < dma_mask from Benjamin Herrenschmidt - EEH fixes for SRIOV from Gavin - introduce rtas_get_sensor_fast() for IRQ handlers from Thomas Huth - use hardware RNG for arch_get_random_seed_* not arch_get_random_* from Paul Mackerras - seccomp filter support from Michael Ellerman - opal_cec_reboot2() handling for HMIs & machine checks from Mahesh Salgaonkar - add powerpc timebase as a trace clock source from Naveen N. Rao - misc cleanups in the xmon, signal & SLB code from Anshuman Khandual - add an inline function to update POWER8 HID0 from Gautham R. Shenoy - fix pte_pagesize_index() crash on 4K w/64K hash from Michael Ellerman - drop support for 64K local store on 4K kernels from Michael Ellerman - move dma_get_required_mask() from pnv_phb to pci_controller_ops from Andrew Donnellan - initialize distance lookup table from drconf path from Nikunj A Dadhania - enable RTC class support from Vaibhav Jain - disable automatically blocked PCI config from Gavin Shan - add LEDs driver for PowerNV platform from Vasant Hegde - fix endianness issues in the HVSI driver from Laurent Dufour - kexec endian fixes from Samuel Mendoza-Jonas - fix corrupted pdn list from Gavin Shan - fix fenced PHB caused by eeh_slot_error_detail() from Gavin Shan - Freescale updates from Scott: Highlights include 32-bit memcpy/memset optimizations, checksum optimizations, 85xx config fragments and updates, device tree updates, e6500 fixes for non-SMP, and misc cleanup and minor fixes. - a ton of cxl updates & fixes: - add explicit precision specifiers from Rasmus Villemoes - use more common format specifier from Rasmus Villemoes - destroy cxl_adapter_idr on module_exit from Johannes Thumshirn - destroy afu->contexts_idr on release of an afu from Johannes Thumshirn - compile with -Werror from Daniel Axtens - EEH support from Daniel Axtens - plug irq_bitmap getting leaked in cxl_context from Vaibhav Jain - add alternate MMIO error handling from Ian Munsie - allow release of contexts which have been OPENED but not STARTED from Andrew Donnellan - remove use of macro DEFINE_PCI_DEVICE_TABLE from Vaishali Thakkar - release irqs if memory allocation fails from Vaibhav Jain - remove racy attempt to force EEH invocation in reset from Daniel Axtens - fix + cleanup error paths in cxl_dev_context_init from Ian Munsie - fix force unmapping mmaps of contexts allocated through the kernel api from Ian Munsie - set up and enable PSL Timebase from Philippe Bergheaud * tag 'powerpc-4.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (140 commits) cxl: Set up and enable PSL Timebase cxl: Fix force unmapping mmaps of contexts allocated through the kernel api cxl: Fix + cleanup error paths in cxl_dev_context_init powerpc/eeh: Fix fenced PHB caused by eeh_slot_error_detail() powerpc/pseries: Cleanup on pci_dn_reconfig_notifier() powerpc/pseries: Fix corrupted pdn list powerpc/powernv: Enable LEDS support powerpc/iommu: Set default DMA offset in dma_dev_setup cxl: Remove racy attempt to force EEH invocation in reset cxl: Release irqs if memory allocation fails cxl: Remove use of macro DEFINE_PCI_DEVICE_TABLE powerpc/powernv: Fix mis-merge of OPAL support for LEDS driver powerpc/powernv: Reset HILE before kexec_sequence() powerpc/kexec: Reset secondary cpu endianness before kexec powerpc/hvsi: Fix endianness issues in the HVSI driver leds/powernv: Add driver for PowerNV platform powerpc/powernv: Create LED platform device powerpc/powernv: Add OPAL interfaces for accessing and modifying system LED states powerpc/powernv: Fix the log message when disabling VF cxl: Allow release of contexts which have been OPENED but not STARTED ...