BMC/Intel-BMC/linux.git/arch/powerpc/mm, branch dev-4.6

powerpc/mm/hash: Fix the reference bit update when handling hash fault

2016-06-24T17:22:03+00:00

commit dc47c0c1f8099fccb2c1e2f3775855066a9e4484 upstream. When we converted the asm routines to C functions, we missed updating HPTE_R_R based on _PAGE_ACCESSED. ASM code used to copy over the lower bits from pte via. andi. r3,r30,0x1fe /* Get basic set of flags */ We also update the code such that we won't update the Change bit ('C' bit) always. This was added by commit c5cf0e30bf3d8 ("powerpc: Fix buglet with MMU hash management"). With hash64, we need to make sure that hardware doesn't do a pte update directly. This is because we do end up with entries in TLB with no hash page table entry. This happens because when we find a hash bucket full, we "evict" a more/less random entry from it. When we do that we don't invalidate the TLB (hpte_remove) because we assume the old translation is still technically "valid". For more info look at commit 0608d692463("powerpc/mm: Always invalidate tlb on hpte invalidate and update"). Thus it's critical that valid hash PTEs always have reference bit set and writeable ones have change bit set. We do this by hashing a non-dirty linux PTE as read-only and always setting _PAGE_ACCESSED (and thus R) when hashing anything else in. Any attempt by Linux at clearing those bits also removes the corresponding hash entry. Commit 5cf0e30bf3d8 did that for 'C' bit by enabling 'C' bit always. We don't really need to do that because we never map a RW pte entry without setting 'C' bit. On READ fault on a RW pte entry, we still map it READ only, hence a store update in the page will still cause a hash pte fault. This patch reverts the part of commit c5cf0e30bf3d8 ("[PATCH] powerpc: Fix buglet with MMU hash management") and retain the updatepp part. - If we hit the updatepp path on native, the old code without that commit, would fail to set C bcause native_hpte_updatepp() was implemented to filter the same bits as H_PROTECT and not let C through thus we would "upgrade" a RO HPTE to RW without setting C thus causing the bug. So the real fix in that commit was the change to native_hpte_updatepp Fixes: 89ff725051d1 ("powerpc/mm: Convert __hash_page_64K to C") Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/mm: Fixup preempt underflow with huge pages

2016-03-29T01:08:07+00:00

hugepd_free() used __get_cpu_var() once. Nothing ensured that the code accessing the variable did not migrate from one CPU to another and soon this was noticed by Tiejun Chen in 94b09d755462 ("powerpc/hugetlb: Replace __get_cpu_var with get_cpu_var"). So we had it fixed. Christoph Lameter was doing his __get_cpu_var() replaces and forgot PowerPC. Then he noticed this and sent his fixed up batch again which got applied as 69111bac42f5 ("powerpc: Replace __get_cpu_var uses"). The careful reader will noticed one little detail: get_cpu_var() got replaced with this_cpu_ptr(). So now we have a put_cpu_var() which does a preempt_enable() and nothing that does preempt_disable() so we underflow the preempt counter. Cc: Benjamin Herrenschmidt Cc: Christoph Lameter Cc: stable@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior Reviewed-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman

Merge tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2016-03-19T22:38:41+00:00

Pull powerpc updates from Michael Ellerman: "This was delayed a day or two by some build-breakage on old toolchains which we've now fixed. There's two PCI commits both acked by Bjorn. There's one commit to mm/hugepage.c which is (co)authored by Kirill. Highlights: - Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V - Add POWER9 cputable entry from Michael Neuling - FPU/Altivec/VSX save/restore optimisations from Cyril Bur - Add support for new ftrace ABI on ppc64le from Torsten Duwe Various cleanups & minor fixes from: - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh. General: - atomics: Allow architectures to define their own __atomic_op_* helpers from Boqun Feng - Implement atomic{, 64}_*_return_* variants and acquire/release/ relaxed variants for (cmp)xchg from Boqun Feng - Add powernv_defconfig from Jeremy Kerr - Fix BUG_ON() reporting in real mode from Balbir Singh - Add xmon command to dump OPAL msglog from Andrew Donnellan - Add xmon command to dump process/task similar to ps(1) from Douglas Miller - Clean up memory hotplug failure paths from David Gibson pci/eeh: - Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei Yang. - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan. - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang - PCI: Add pcibios_bus_add_device() weak function from Wei Yang - MAINTAINERS: Update EEH details and maintainership from Russell Currey cxl: - Support added to the CXL driver for running on both bare-metal and hypervisor systems, from Christophe Lombard and Frederic Barrat. - Ignore probes for virtual afu pci devices from Vaibhav Jain perf: - Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu - hv-24x7: Fix usage with chip events, display change in counter values, display domain indices in sysfs, eliminate domain suffix in event names, from Sukadev Bhattiprolu Freescale: - Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and other dt bits, and minor fixes/cleanup" * tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits) powerpc: Fix unrecoverable SLB miss during restore_math() powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers powerpc/rcpm: Fix build break when SMP=n powerpc/book3e-64: Use hardcoded mttmr opcode powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible powerpc/T104xRDB: add tdm riser card node to device tree powerpc32: PAGE_EXEC required for inittext powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s) powerpc/86xx: Introduce and use common dtsi powerpc/86xx: Update device tree powerpc/86xx: Move dts files to fsl directory powerpc/86xx: Switch to kconfig fragments approach powerpc/86xx: Update defconfigs powerpc/86xx: Consolidate common platform code powerpc32: Remove one insn in mulhdu powerpc32: small optimisation in flush_icache_range() powerpc: Simplify test in __dma_sync() powerpc32: move xxxxx_dcache_range() functions inline powerpc32: Remove clear_pages() and define clear_page() inline ...

mm: introduce page reference manipulation functions

2016-03-17T22:09:34+00:00

The success of CMA allocation largely depends on the success of migration and key factor of it is page reference count. Until now, page reference is manipulated by direct calling atomic functions so we cannot follow up who and where manipulate it. Then, it is hard to find actual reason of CMA allocation failure. CMA allocation should be guaranteed to succeed so finding offending place is really important. In this patch, call sites where page reference is manipulated are converted to introduced wrapper function. This is preparation step to add tracepoint to each page reference manipulation function. With this facility, we can easily find reason of CMA allocation failure. There is no functional change in this patch. In addition, this patch also converts reference read sites. It will help a second step that renames page._count to something else and prevents later attempt to direct access to it (Suggested by Andrew). Signed-off-by: Joonsoo Kim Acked-by: Michal Nazarewicz Acked-by: Vlastimil Babka Cc: Minchan Kim Cc: Mel Gorman Cc: "Kirill A. Shutemov" Cc: Sergey Senozhatsky Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

powerpc: query dynamic DEBUG_PAGEALLOC setting

2016-03-17T22:09:34+00:00

We can disable debug_pagealloc processing even if the code is compiled with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query whether it is enabled or not in runtime. Signed-off-by: Joonsoo Kim Acked-by: David Rientjes Cc: Christian Borntraeger Cc: Benjamin Herrenschmidt Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2016-03-16T16:55:35+00:00

Pull KVM updates from Paolo Bonzini: "One of the largest releases for KVM... Hardly any generic changes, but lots of architecture-specific updates. ARM: - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems - PMU support for guests - 32bit world switch rewritten in C - various optimizations to the vgic save/restore code. PPC: - enabled KVM-VFIO integration ("VFIO device") - optimizations to speed up IPIs between vcpus - in-kernel handling of IOMMU hypercalls - support for dynamic DMA windows (DDW). s390: - provide the floating point registers via sync regs; - separated instruction vs. data accesses - dirty log improvements for huge guests - bugfixes and documentation improvements. x86: - Hyper-V VMBus hypercall userspace exit - alternative implementation of lowest-priority interrupts using vector hashing (for better VT-d posted interrupt support) - fixed guest debugging with nested virtualizations - improved interrupt tracking in the in-kernel IOAPIC - generic infrastructure for tracking writes to guest memory - currently its only use is to speedup the legacy shadow paging (pre-EPT) case, but in the future it will be used for virtual GPUs as well - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits) KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch KVM: x86: disable MPX if host did not enable MPX XSAVE features arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit arm64: KVM: vgic-v3: Reset LRs at boot time arm64: KVM: vgic-v3: Do not save an LR known to be empty arm64: KVM: vgic-v3: Save maintenance interrupt state only if required arm64: KVM: vgic-v3: Avoid accessing ICH registers KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit KVM: arm/arm64: vgic-v2: Reset LRs at boot time KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers KVM: s390: allocate only one DMA page per VM KVM: s390: enable STFLE interpretation only if enabled for the guest KVM: s390: wake up when the VCPU cpu timer expires KVM: s390: step the VCPU timer while in enabled wait KVM: s390: protect VCPU cpu timer with a seqcount KVM: s390: step VCPU cpu timer during kvm_run ioctl ...

Merge branch 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-03-14T22:15:51+00:00

Pull ram resource handling changes from Ingo Molnar: "Core kernel resource handling changes to support NVDIMM error injection. This tree introduces a new I/O resource type, IORESOURCE_SYSTEM_RAM, for System RAM while keeping the current IORESOURCE_MEM type bit set for all memory-mapped ranges (including System RAM) for backward compatibility. With this resource flag it no longer takes a strcmp() loop through the resource tree to find "System RAM" resources. The new resource type is then used to extend ACPI/APEI error injection facility to also support NVDIMM" * 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ACPI/EINJ: Allow memory error injection to NVDIMM resource: Kill walk_iomem_res() x86/kexec: Remove walk_iomem_res() call with GART type x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem search resource: Add walk_iomem_res_desc() memremap: Change region_intersects() to take @flags and @desc arm/samsung: Change s3c_pm_run_res() to use System RAM type resource: Change walk_system_ram() to use System RAM type drivers: Initialize resource entry to zero xen, mm: Set IORESOURCE_SYSTEM_RAM to System RAM kexec: Set IORESOURCE_SYSTEM_RAM for System RAM arch: Set IORESOURCE_SYSTEM_RAM flag for System RAM ia64: Set System RAM type and descriptor x86/e820: Set System RAM type and descriptor resource: Add I/O resource descriptor resource: Handle resource flags properly resource: Add System RAM resource type

powerpc32: PAGE_EXEC required for inittext

2016-03-12T02:04:32+00:00

PAGE_EXEC is required for inittext, otherwise CONFIG_DEBUG_PAGEALLOC ends up with an Oops [ 0.000000] Inode-cache hash table entries: 8192 (order: 1, 32768 bytes) [ 0.000000] Sorting __ex_table... [ 0.000000] bootmem::free_all_bootmem_core nid=0 start=0 end=2000 [ 0.000000] Unable to handle kernel paging request for instruction fetch [ 0.000000] Faulting instruction address: 0xc045b970 [ 0.000000] Oops: Kernel access of bad area, sig: 11 [#1] [ 0.000000] PREEMPT DEBUG_PAGEALLOC CMPC885 [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 3.18.25-local-dirty #1673 [ 0.000000] task: c04d83d0 ti: c04f8000 task.ti: c04f8000 [ 0.000000] NIP: c045b970 LR: c045b970 CTR: 0000000a [ 0.000000] REGS: c04f9ea0 TRAP: 0400 Not tainted (3.18.25-local-dirty) [ 0.000000] MSR: 08001032 CR: 39955d35 XER: a000ff40 [ 0.000000] GPR00: c045b970 c04f9f50 c04d83d0 00000000 ffffffff c04dcdf4 00000048 c04f6b10 GPR08: c04f6ab0 00000001 c0563488 c04f6ab0 c04f8000 00000000 00000000 b6db6db7 GPR16: 00003474 00000180 00002000 c7fec000 00000000 000003ff 00000176 c0415014 GPR24: c0471018 c0414ee8 c05304e8 c03aeaac c0510000 c0471018 c0471010 00000000 [ 0.000000] NIP [c045b970] free_all_bootmem+0x164/0x228 [ 0.000000] LR [c045b970] free_all_bootmem+0x164/0x228 [ 0.000000] Call Trace: [ 0.000000] [c04f9f50] [c045b970] free_all_bootmem+0x164/0x228 (unreliable) [ 0.000000] [c04f9fa0] [c0454044] mem_init+0x3c/0xd0 [ 0.000000] [c04f9fb0] [c045080c] start_kernel+0x1f4/0x390 [ 0.000000] [c04f9ff0] [c0002214] start_here+0x38/0x98 [ 0.000000] Instruction dump: [ 0.000000] 2f150000 7f968840 72a90001 3ad60001 56b5f87e 419a0028 419e0024 41a20018 [ 0.000000] 807cc20c 38800000 7c638214 4bffd2f5 <3a940001> 3a100024 4bffffc8 7e368b78 [ 0.000000] ---[ end trace dc8fa200cb88537f ]--- Signed-off-by: Christophe Leroy Signed-off-by: Scott Wood

powerpc: Simplify test in __dma_sync()

2016-03-11T23:20:12+00:00

This simplification helps the compiler. We now have only one test instead of two, so it reduces the number of branches. Signed-off-by: Christophe Leroy Signed-off-by: Scott Wood

powerpc/8xx: rewrite flush_instruction_cache() in C

2016-03-11T23:20:11+00:00

On PPC8xx, flushing instruction cache is performed by writing in register SPRN_IC_CST. This registers suffers CPU6 ERRATA. The patch rewrites the fonction in C so that CPU6 ERRATA will be handled transparently Signed-off-by: Christophe Leroy Signed-off-by: Scott Wood