kernel/arch/powerpc/mm, branch linux-4.3.y

powerpc: Fix checkstop in native_hpte_clear() with lockdep

2015-10-08T21:01:38Z

native_hpte_clear() is called in real mode from two places: - Early in boot during htab initialisation if firmware assisted dump is active. - Late in the kexec path. In both contexts there is no need to disable interrupts are they are already disabled. Furthermore, locking around the tlbie() is only required for pre POWER5 hardware. On POWER5 or newer hardware concurrent tlbie()s work as expected and on pre POWER5 hardware concurrent tlbie()s could result in deadlock. This code would only be executed at crashdump time, during which all bets are off, concurrent tlbie()s are unlikely and taking locks is unsafe therefore the best course of action is to simply do nothing. Concurrent tlbie()s are not possible in the first case as secondary CPUs have not come up yet. Signed-off-by: Cyril Bur Signed-off-by: Michael Ellerman

Merge tag 'powerpc-4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2015-09-18T15:01:06Z

Pull powerpc fixes from Michael Ellerman: - Fix 32-bit TCE table init in kdump kernel from Nish - Fix kdump with non-power-of-2 crashkernel= from Nish - Abort cxl_pci_enable_device_hook() if PCI channel is offline from Andrew - Fix to release DRC when configure_connector() fails from Bharata - Wire up sys_userfaultfd() - Fix race condition in tearing down MSI interrupts from Paul - Fix unbalanced pci_dev_get() in cxl_probe() from Daniel - Fix cxl build failure due to -Wunused-variable gcc behaviour change from Ian - Tell the toolchain to use ABI v2 when building an LE boot wrapper from Benh - Fix THP to recompute hash value after a failed update from Aneesh - 32-bit memcpy/memset: only use dcbz once cache is enabled from Christophe * tag 'powerpc-4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc32: memset: only use dcbz once cache is enabled powerpc32: memcpy: only use dcbz once cache is enabled powerpc/mm: Recompute hash value after a failed update powerpc/boot: Specify ABI v2 when building an LE boot wrapper cxl: Fix build failure due to -Wunused-variable behaviour change cxl: Fix unbalanced pci_dev_get in cxl_probe powerpc/MSI: Fix race condition in tearing down MSI interrupts powerpc: Wire up sys_userfaultfd() powerpc/pseries: Release DRC when configure_connector fails cxl: abort cxl_pci_enable_device_hook() if PCI channel is offline powerpc/powernv/pci-ioda: fix kdump with non-power-of-2 crashkernel= powerpc/powernv/pci-ioda: fix 32-bit TCE table init in kdump kernel

powerpc/mm: Recompute hash value after a failed update

2015-09-16T12:06:03Z

If we had secondary hash flag set, we ended up modifying hash value in the updatepp code path. Hence with a failed updatepp we will be using a wrong hash value for the following hash insert. Fix this by recomputing hash before insert. Without this patch we can end up with using wrong slot number in linux pte. That can result in us missing an hash pte update or invalidate which can cause memory corruption or even machine check. Fixes: 6d492ecc6489 ("powerpc/THP: Add code to handle HPTE faults for hugepages") Cc: stable@vger.kernel.org # v3.11+ Signed-off-by: Aneesh Kumar K.V Reviewed-by: Paul Mackerras Signed-off-by: Michael Ellerman

Merge tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2015-09-08T21:35:59Z

Pull libnvdimm updates from Dan Williams: "This update has successfully completed a 0day-kbuild run and has appeared in a linux-next release. The changes outside of the typical drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and the introduction of ZONE_DEVICE + devm_memremap_pages(). Summary: - Introduce ZONE_DEVICE and devm_memremap_pages() as a generic mechanism for adding device-driver-discovered memory regions to the kernel's direct map. This facility is used by the pmem driver to enable pfn_to_page() operations on the page frames returned by DAX ('direct_access' in 'struct block_device_operations'). For now, the 'memmap' allocation for these "device" pages comes from "System RAM". Support for allocating the memmap from device memory will arrive in a later kernel. - Introduce memremap() to replace usages of ioremap_cache() and ioremap_wt(). memremap() drops the __iomem annotation for these mappings to memory that do not have i/o side effects. The replacement of ioremap_cache() with memremap() is limited to the pmem driver to ease merging the api change in v4.3. Completion of the conversion is targeted for v4.4. - Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem driver, update the VFS DAX implementation and PMEM api to provide persistence guarantees for kernel operations on a DAX mapping. - Convert the ACPI NFIT 'BLK' driver to map the block apertures as cacheable to improve performance. - Miscellaneous updates and fixes to libnvdimm including support for issuing "address range scrub" commands, clarifying the optimal 'sector size' of pmem devices, a clarification of the usage of the ACPI '_STA' (status) property for DIMM devices, and other minor fixes" * tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits) libnvdimm, pmem: direct map legacy pmem by default libnvdimm, pmem: 'struct page' for pmem libnvdimm, pfn: 'struct page' provider infrastructure x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB add devm_memremap_pages mm: ZONE_DEVICE for "device memory" mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h dax: drop size parameter to ->direct_access() nd_blk: change aperture mapping from WC to WB nvdimm: change to use generic kvfree() pmem, dax: have direct_access use __pmem annotation dax: update I/O path to do proper PMEM flushing pmem: add copy_from_iter_pmem() and clear_pmem() pmem, x86: clean up conditional pmem includes pmem: remove layer when calling arch_has_wmb_pmem() pmem, x86: move x86 PMEM API to new pmem.h header libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option pmem: switch to devm_ allocations devres: add devm_memremap libnvdimm, btt: write and validate parent_uuid ...

mm: ZONE_DEVICE for "device memory"

2015-08-27T23:40:58Z

While pmem is usable as a block device or via DAX mappings to userspace there are several usage scenarios that can not target pmem due to its lack of struct page coverage. In preparation for "hot plugging" pmem into the vmemmap add ZONE_DEVICE as a new zone to tag these pages separately from the ones that are subject to standard page allocations. Importantly "device memory" can be removed at will by userspace unbinding the driver of the device. Having a separate zone prevents allocation and otherwise marks these pages that are distinct from typical uniform memory. Device memory has different lifetime and performance characteristics than RAM. However, since we have run out of ZONES_SHIFT bits this functionality currently depends on sacrificing ZONE_DMA. Cc: H. Peter Anvin Cc: Ingo Molnar Cc: Dave Hansen Cc: Rik van Riel Cc: Mel Gorman Cc: Jerome Glisse [hch: various simplifications in the arch interface] Signed-off-by: Christoph Hellwig Signed-off-by: Dan Williams

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next

2015-08-27T10:13:12Z

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."

powerpc/numa: initialize distance lookup table from drconf path

2015-08-18T09:34:41Z

In some situations, a NUMA guest that supports ibm,dynamic-memory-reconfiguration node will end up having flat NUMA distances between nodes. This is because of two problems in the current code. 1) Different representations of associativity lists. There is an assumption about the associativity list in initialize_distance_lookup_table(). Associativity list has two forms: a) [cpu,memory]@x/ibm,associativity has following format: b) ibm,dynamic-reconfiguration-memory/ibm,associativity-lookup-arrays M = the number of associativity lists N = the number of entries per associativity list Fix initialize_distance_lookup_table() so that it does not assume "case a". And update the caller to skip the length field before sending the associativity list. 2) Distance table not getting updated from drconf path. Node distance table will not get initialized in certain cases as ibm,dynamic-reconfiguration-memory path does not initialize the lookup table. Call initialize_distance_lookup_table() from drconf path with appropriate associativity list. Reported-by: Bharata B Rao Signed-off-by: Nikunj A Dadhania Acked-by: Anton Blanchard Signed-off-by: Michael Ellerman

powerpc/mm: Drop CONFIG_PPC_HAS_HASH_64K

2015-08-18T09:32:10Z

The relation between CONFIG_PPC_HAS_HASH_64K and CONFIG_PPC_64K_PAGES is painfully complicated. But if we rearrange it enough we can see that PPC_HAS_HASH_64K essentially depends on PPC_STD_MMU_64 && PPC_64K_PAGES. We can then notice that PPC_HAS_HASH_64K is used in files that are only built for PPC_STD_MMU_64, meaning it's equivalent to PPC_64K_PAGES. So replace all uses and drop it. Signed-off-by: Michael Ellerman Reviewed-by: Aneesh Kumar K.V

powerpc/cell: Drop support for 64K local store on 4K kernels

2015-08-18T09:29:49Z

Back in the olden days we added support for using 64K pages to map the SPU (Synergistic Processing Unit) local store on Cell, when the main kernel was using 4K pages. This was useful at the time because distros were using 4K pages, but using 64K pages on the SPUs could reduce TLB pressure there. However these days the number of Cell users is approaching zero, and supporting this option adds unpleasant complexity to the memory management code. So drop the option, CONFIG_SPU_FS_64K_LS, and all related code. Signed-off-by: Michael Ellerman Acked-by: Jeremy Kerr

powerpc/e6500: hw tablewalk: optimize a bit for tcd lock acquiring codes

2015-08-17T23:53:47Z

It makes no sense to put the instructions for calculating the lock value (cpu number + 1) and the clearing of eq bit of cr1 in lbarx/stbcx loop. And when the lock is acquired by the other thread, the current lock value has no chance to equal with the lock value used by current cpu. So we can skip the comparing for these two lock values in the lbz/bne loop. Signed-off-by: Kevin Hao Signed-off-by: Scott Wood