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2018-06-06Merge tag 'kbuild-v4.18' of ↵Linus Torvalds2-11/+12
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - improve fixdep to coalesce consecutive slashes in dep-files - fix some issues of the maintainer string generation in deb-pkg script - remove unused CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX and clean-up several tools and linker scripts - clean-up modpost - allow to enable the dead code/data elimination for PowerPC in EXPERT mode - improve two coccinelle scripts for better performance - pass endianness and machine size flags to sparse for all architecture - misc fixes * tag 'kbuild-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) kbuild: add machine size to CHECKFLAGS kbuild: add endianness flag to CHEKCFLAGS kbuild: $(CHECK) doesnt need NOSTDINC_FLAGS twice scripts: Fixed printf format mismatch scripts/tags.sh: use `find` for $ALLSOURCE_ARCHS generation coccinelle: deref_null: improve performance coccinelle: mini_lock: improve performance powerpc: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selected kbuild: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selectable if enabled kbuild: LD_DEAD_CODE_DATA_ELIMINATION no -ffunction-sections/-fdata-sections for module build kbuild: Fix asm-generic/vmlinux.lds.h for LD_DEAD_CODE_DATA_ELIMINATION modpost: constify *modname function argument where possible modpost: remove redundant is_vmlinux() test modpost: use strstarts() helper more widely modpost: pass struct elf_info pointer to get_modinfo() checkpatch: remove VMLINUX_SYMBOL() check vmlinux.lds.h: remove no-op macro VMLINUX_SYMBOL() kbuild: remove CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX export.h: remove code for prefixing symbols with underscore depmod.sh: remove symbol prefix support ...
2018-06-06Merge tag 'char-misc-4.18-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the "big" char and misc driver patches for 4.18-rc1. It's not a lot of stuff here, but there are some highlights: - coreboot driver updates - soundwire driver updates - android binder updates - fpga big sync, mostly documentation - lots of minor driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (81 commits) vmw_balloon: fixing double free when batching mode is off MAINTAINERS: Add driver-api/fpga path fpga: clarify that unregister functions also free documentation: fpga: move fpga-region.txt to driver-api documentation: fpga: add bridge document to driver-api documentation: fpga: move fpga-mgr.txt to driver-api Documentation: fpga: move fpga overview to driver-api fpga: region: kernel-doc fixes fpga: bridge: kernel-doc fixes fpga: mgr: kernel-doc fixes fpga: use SPDX fpga: region: change api, add fpga_region_create/free fpga: bridge: change api, don't use drvdata fpga: manager: change api, don't use drvdata fpga: region: don't use drvdata in common fpga code Drivers: hv: vmbus: Removed an unnecessary cast from void * ver_linux: Drop redundant calls to system() to test if file is readable ver_linux: Move stderr redirection from function parameter to function body misc: IBM Virtual Management Channel Driver (VMC) rpmsg: Correct support for MODULE_DEVICE_TABLE() ...
2018-06-05Merge branch 'timers-2038-for-linus' of ↵Linus Torvalds4-43/+40
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull time/Y2038 updates from Thomas Gleixner: - Consolidate SySV IPC UAPI headers - Convert SySV IPC to the new COMPAT_32BIT_TIME mechanism - Cleanup the core interfaces and standardize on the ktime_get_* naming convention. - Convert the X86 platform ops to timespec64 - Remove the ugly temporary timespec64 hack * 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86: Convert x86_platform_ops to timespec64 timekeeping: Add more coarse clocktai/boottime interfaces timekeeping: Add ktime_get_coarse_with_offset timekeeping: Standardize on ktime_get_*() naming timekeeping: Clean up ktime_get_real_ts64 timekeeping: Remove timespec64 hack y2038: ipc: Redirect ipc(SEMTIMEDOP, ...) to compat_ksys_semtimedop y2038: ipc: Enable COMPAT_32BIT_TIME y2038: ipc: Use __kernel_timespec y2038: ipc: Report long times to user space y2038: ipc: Use ktime_get_real_seconds consistently y2038: xtensa: Extend sysvipc data structures y2038: powerpc: Extend sysvipc data structures y2038: sparc: Extend sysvipc data structures y2038: parisc: Extend sysvipc data structures y2038: mips: Extend sysvipc data structures y2038: arm64: Extend sysvipc compat data structures y2038: s390: Remove unneeded ipc uapi header files y2038: ia64: Remove unneeded ipc uapi header files y2038: alpha: Remove unneeded ipc uapi header files ...
2018-06-05Merge branch 'timers-core-for-linus' of ↵Linus Torvalds3-12/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timers and timekeeping updates from Thomas Gleixner: - Core infrastucture work for Y2038 to address the COMPAT interfaces: + Add a new Y2038 safe __kernel_timespec and use it in the core code + Introduce config switches which allow to control the various compat mechanisms + Use the new config switch in the posix timer code to control the 32bit compat syscall implementation. - Prevent bogus selection of CPU local clocksources which causes an endless reselection loop - Remove the extra kthread in the clocksource code which has no value and just adds another level of indirection - The usual bunch of trivial updates, cleanups and fixlets all over the place - More SPDX conversions * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) clocksource/drivers/mxs_timer: Switch to SPDX identifier clocksource/drivers/timer-imx-tpm: Switch to SPDX identifier clocksource/drivers/timer-imx-gpt: Switch to SPDX identifier clocksource/drivers/timer-imx-gpt: Remove outdated file path clocksource/drivers/arc_timer: Add comments about locking while read GFRC clocksource/drivers/mips-gic-timer: Add pr_fmt and reword pr_* messages clocksource/drivers/sprd: Fix Kconfig dependency clocksource: Move inline keyword to the beginning of function declarations timer_list: Remove unused function pointer typedef timers: Adjust a kernel-doc comment tick: Prefer a lower rating device only if it's CPU local device clocksource: Remove kthread time: Change nanosleep to safe __kernel_* types time: Change types to new y2038 safe __kernel_* types time: Fix get_timespec64() for y2038 safe compat interfaces time: Add new y2038 safe __kernel_timespec posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME time: Introduce CONFIG_COMPAT_32BIT_TIME time: Introduce CONFIG_64BIT_TIME in architectures compat: Enable compat_get/put_timespec64 always ...
2018-06-05Merge branch 'irq-core-for-linus' of ↵Linus Torvalds1-7/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: - Consolidation of softirq pending: The softirq mask and its accessors/mutators have many implementations scattered around many architectures. Most do the same things consisting in a field in a per-cpu struct (often irq_cpustat_t) accessed through per-cpu ops. We can provide instead a generic efficient version that most of them can use. In fact s390 is the only exception because the field is stored in lowcore. - Support for level!?! triggered MSI (ARM) Over the past couple of years, we've seen some SoCs coming up with ways of signalling level interrupts using a new flavor of MSIs, where the MSI controller uses two distinct messages: one that raises a virtual line, and one that lowers it. The target MSI controller is in charge of maintaining the state of the line. This allows for a much simplified HW signal routing (no need to have hundreds of discrete lines to signal level interrupts if you already have a memory bus), but results in a departure from the current idea the kernel has of MSIs. - Support for Meson-AXG GPIO irqchip - Large stm32 irqchip rework (suspend/resume, hierarchical domains) - More SPDX conversions * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) ARM: dts: stm32: Add exti support to stm32mp157 pinctrl ARM: dts: stm32: Add exti support for stm32mp157c pinctrl/stm32: Add irq_eoi for stm32gpio irqchip irqchip/stm32: Add suspend/resume support for hierarchy domain irqchip/stm32: Add stm32mp1 support with hierarchy domain irqchip/stm32: Prepare common functions irqchip/stm32: Add host and driver data structures irqchip/stm32: Add suspend support irqchip/stm32: Add falling pending register support irqchip/stm32: Checkpatch fix irqchip/stm32: Optimizes and cleans up stm32-exti irq_domain irqchip/meson-gpio: Add support for Meson-AXG SoCs dt-bindings: interrupt-controller: New binding for Meson-AXG SoC dt-bindings: interrupt-controller: Fix the double quotes softirq/s390: Move default mutators of overwritten softirq mask to s390 softirq/x86: Switch to generic local_softirq_pending() implementation softirq/sparc: Switch to generic local_softirq_pending() implementation softirq/powerpc: Switch to generic local_softirq_pending() implementation softirq/parisc: Switch to generic local_softirq_pending() implementation softirq/ia64: Switch to generic local_softirq_pending() implementation ...
2018-06-05Merge branch 'siginfo-linus' of ↵Linus Torvalds5-23/+9
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull siginfo updates from Eric Biederman: "This set of changes close the known issues with setting si_code to an invalid value, and with not fully initializing struct siginfo. There remains work to do on nds32, arc, unicore32, powerpc, arm, arm64, ia64 and x86 to get the code that generates siginfo into a simpler and more maintainable state. Most of that work involves refactoring the signal handling code and thus careful code review. Also not included is the work to shrink the in kernel version of struct siginfo. That depends on getting the number of places that directly manipulate struct siginfo under control, as it requires the introduction of struct kernel_siginfo for the in kernel things. Overall this set of changes looks like it is making good progress, and with a little luck I will be wrapping up the siginfo work next development cycle" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits) signal/sh: Stop gcc warning about an impossible case in do_divide_error signal/mips: Report FPE_FLTUNK for undiagnosed floating point exceptions signal/um: More carefully relay signals in relay_signal. signal: Extend siginfo_layout with SIL_FAULT_{MCEERR|BNDERR|PKUERR} signal: Remove unncessary #ifdef SEGV_PKUERR in 32bit compat code signal/signalfd: Add support for SIGSYS signal/signalfd: Remove __put_user from signalfd_copyinfo signal/xtensa: Use force_sig_fault where appropriate signal/xtensa: Consistenly use SIGBUS in do_unaligned_user signal/um: Use force_sig_fault where appropriate signal/sparc: Use force_sig_fault where appropriate signal/sparc: Use send_sig_fault where appropriate signal/sh: Use force_sig_fault where appropriate signal/s390: Use force_sig_fault where appropriate signal/riscv: Replace do_trap_siginfo with force_sig_fault signal/riscv: Use force_sig_fault where appropriate signal/parisc: Use force_sig_fault where appropriate signal/parisc: Use force_sig_mceerr where appropriate signal/openrisc: Use force_sig_fault where appropriate signal/nios2: Use force_sig_fault where appropriate ...
2018-06-04Merge tag 'docs-4.18' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull documentation updates from Jonathan Corbet: "There's been a fair amount of work in the docs tree this time around, including: - Extensive RST conversions and organizational work in the memory-management docs thanks to Mike Rapoport. - An update of Documentation/features from Andrea Parri and a script to keep it updated. - Various LICENSES updates from Thomas, along with a script to check SPDX tags. - Work to fix dangling references to documentation files; this involved a fair number of one-liner comment changes outside of Documentation/ ... and the usual list of documentation improvements, typo fixes, etc" * tag 'docs-4.18' of git://git.lwn.net/linux: (103 commits) Documentation: document hung_task_panic kernel parameter docs/admin-guide/mm: add high level concepts overview docs/vm: move ksm and transhuge from "user" to "internals" section. docs: Use the kerneldoc comments for memalloc_no*() doc: document scope NOFS, NOIO APIs docs: update kernel versions and dates in tables docs/vm: transhuge: split userspace bits to admin-guide/mm/transhuge docs/vm: transhuge: minor updates docs/vm: transhuge: change sections order Documentation: arm: clean up Marvell Berlin family info Documentation: gpio: driver: Fix a typo and some odd grammar docs: ranoops.rst: fix location of ramoops.txt scripts/documentation-file-ref-check: rewrite it in perl with auto-fix mode docs: uio-howto.rst: use a code block to solve a warning mm, THP, doc: Add document for thp_swpout/thp_swpout_fallback w1: w1_io.c: fix a kernel-doc warning Documentation/process/posting: wrap text at 80 cols docs: admin-guide: add cgroup-v2 documentation Revert "Documentation/features/vm: Remove arch support status file for 'pte_special'" Documentation: refcount-vs-atomic: Update reference to LKMM doc. ...
2018-06-04Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds4-44/+3
Pull dma-mapping updates from Christoph Hellwig: - replace the force_dma flag with a dma_configure bus method. (Nipun Gupta, although one patch is іncorrectly attributed to me due to a git rebase bug) - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai) - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the right thing for bounce buffering. - move dma-debug initialization to common code, and apply a few cleanups to the dma-debug code. - cleanup the Kconfig mess around swiotlb selection - swiotlb comment fixup (Yisheng Xie) - a trivial swiotlb fix. (Dan Carpenter) - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt) - add a new generic dma-noncoherent dma_map_ops implementation and use it for arc, c6x and nds32. - improve scatterlist validity checking in dma-debug. (Robin Murphy) - add a struct device quirk to limit the dma-mask to 32-bit due to bridge/system issues, and switch x86 to use it instead of a local hack for VIA bridges. - handle devices without a dma_mask more gracefully in the dma-direct code. * tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits) dma-direct: don't crash on device without dma_mask nds32: use generic dma_noncoherent_ops nds32: implement the unmap_sg DMA operation nds32: consolidate DMA cache maintainance routines x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag x86/pci-dma: remove the explicit nodac and allowdac option x86/pci-dma: remove the experimental forcesac boot option Documentation/x86: remove a stray reference to pci-nommu.c core, dma-direct: add a flag 32-bit dma limits dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs dma-debug: check scatterlist segments c6x: use generic dma_noncoherent_ops arc: use generic dma_noncoherent_ops arc: fix arc_dma_{map,unmap}_page arc: fix arc_dma_sync_sg_for_{cpu,device} arc: simplify arc_dma_sync_single_for_{cpu,device} dma-mapping: provide a generic dma-noncoherent implementation dma-mapping: simplify Kconfig dependencies riscv: add swiotlb support riscv: only enable ZONE_DMA32 for 64-bit ...
2018-06-04Merge branch 'hch.procfs' of ↵Linus Torvalds3-54/+6
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull procfs updates from Al Viro: "Christoph's proc_create_... cleanups series" * 'hch.procfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (44 commits) xfs, proc: hide unused xfs procfs helpers isdn/gigaset: add back gigaset_procinfo assignment proc: update SIZEOF_PDE_INLINE_NAME for the new pde fields tty: replace ->proc_fops with ->proc_show ide: replace ->proc_fops with ->proc_show ide: remove ide_driver_proc_write isdn: replace ->proc_fops with ->proc_show atm: switch to proc_create_seq_private atm: simplify procfs code bluetooth: switch to proc_create_seq_data netfilter/x_tables: switch to proc_create_seq_private netfilter/xt_hashlimit: switch to proc_create_{seq,single}_data neigh: switch to proc_create_seq_data hostap: switch to proc_create_{seq,single}_data bonding: switch to proc_create_seq_data rtc/proc: switch to proc_create_single_data drbd: switch to proc_create_single resource: switch to proc_create_seq_data staging/rtl8192u: simplify procfs code jfs: simplify procfs code ...
2018-05-26Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds6-55/+159
Pull KVM fixes from Radim Krčmář: "PPC: - Close a hole which could possibly lead to the host timebase getting out of sync. - Three fixes relating to PTEs and TLB entries for radix guests. - Fix a bug which could lead to an interrupt never getting delivered to the guest, if it is pending for a guest vCPU when the vCPU gets offlined. s390: - Fix false negatives in VSIE validity check (Cc stable) x86: - Fix time drift of VMX preemption timer when a guest uses LAPIC timer in periodic mode (Cc stable) - Unconditionally expose CPUID.IA32_ARCH_CAPABILITIES to allow migration from hosts that don't need retpoline mitigation (Cc stable) - Fix guest crashes on reboot by properly coupling CR4.OSXSAVE and CPUID.OSXSAVE (Cc stable) - Report correct RIP after Hyper-V hypercall #UD (introduced in -rc6)" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: fix #UD address of failed Hyper-V hypercalls kvm: x86: IA32_ARCH_CAPABILITIES is always supported KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed x86/kvm: fix LAPIC timer drift when guest uses periodic mode KVM: s390: vsie: fix < 8k check for the itdba KVM: PPC: Book 3S HV: Do ptesync in radix guest exit path KVM: PPC: Book3S HV: XIVE: Resend re-routed interrupts on CPU priority change KVM: PPC: Book3S HV: Make radix clear pte when unmapping KVM: PPC: Book3S HV: Make radix use correct tlbie sequence in kvmppc_radix_tlbie_page KVM: PPC: Book3S HV: Snapshot timebase offset on guest entry
2018-05-25Merge tag 'powerpc-4.17-7' of ↵Linus Torvalds2-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fix from Michael Ellerman: "Just one fix, to make sure the PCR (Processor Compatibility Register) is reset on boot. Otherwise if we're running in compat mode in a guest (eg. pretending a Power9 is a Power8) and the host kernel oopses and kdumps then the kdump kernel's userspace will be running in Power8 mode, and will SIGILL if it uses Power9-only instructions. Thanks to Michael Neuling" * tag 'powerpc-4.17-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64s: Clear PCR on boot
2018-05-22powerpc/64s: Add support for a store forwarding barrier at kernel entry/exitNicholas Piggin9-2/+356
On some CPUs we can prevent a vulnerability related to store-to-load forwarding by preventing store forwarding between privilege domains, by inserting a barrier in kernel entry and exit paths. This is known to be the case on at least Power7, Power8 and Power9 powerpc CPUs. Barriers must be inserted generally before the first load after moving to a higher privilege, and after the last store before moving to a lower privilege, HV and PR privilege transitions must be protected. Barriers are added as patch sections, with all kernel/hypervisor entry points patched, and the exit points to lower privilge levels patched similarly to the RFI flush patching. Firmware advertisement is not implemented yet, so CPU flush types are hard coded. Thanks to Michal Suchánek for bug fixes and review. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michal Suchánek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-19Merge branch 'linus' into timers/2038Thomas Gleixner18-72/+191
Merge upstream to pick up changes on which pending patches depend on.
2018-05-18powerpc/64s: Clear PCR on bootMichael Neuling2-0/+7
Clear the PCR (Processor Compatibility Register) on boot to ensure we are not running in a compatibility mode. We've seen this cause problems when a crash (and kdump) occurs while running compat mode guests. The kdump kernel then runs with the PCR set and causes problems. The symptom in the kdump kernel (also seen in petitboot after fast-reboot) is early userspace programs taking sigills on newer instructions (seen in libc). Signed-off-by: Michael Neuling <mikey@neuling.org> Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-17powerpc/powernv: Fix NVRAM sleep in invalid context when crashingNicholas Piggin1-2/+12
Similarly to opal_event_shutdown, opal_nvram_write can be called in the crash path with irqs disabled. Special case the delay to avoid sleeping in invalid context. Fixes: 3b8070335f75 ("powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops") Cc: stable@vger.kernel.org # v3.2 Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-17powerpc: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selectedNicholas Piggin2-11/+12
This requires further changes to linker script to KEEP some tables and wildcard compiler generated sections into the right place. This includes pp32 modifications from Christophe Leroy. When compiling powernv_defconfig with this option, the resulting kernel is almost 400kB smaller (and still boots): text data bss dec filename 11827621 4810490 1341080 17979191 vmlinux 11752437 4598858 1338776 17690071 vmlinux.dcde Mathieu's numbers for custom Mac Mini G4 config has almost 200kB saving. It also had some increase in vmlinux size for as-yet unknown reasons. text data bss dec filename 7461457 2475122 1428064 11364643 vmlinux 7386425 2364370 1425432 11176227 vmlinux.dcde Tested-by: Christophe Leroy <christophe.leroy@c-s.fr> [8xx] Tested-by: Mathieu Malaterre <malat@debian.org> [32-bit powermac] Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-17KVM: PPC: Book 3S HV: Do ptesync in radix guest exit pathPaul Mackerras1-0/+8
A radix guest can execute tlbie instructions to invalidate TLB entries. After a tlbie or a group of tlbies, it must then do the architected sequence eieio; tlbsync; ptesync to ensure that the TLB invalidation has been processed by all CPUs in the system before it can rely on no CPU using any translation that it just invalidated. In fact it is the ptesync which does the actual synchronization in this sequence, and hardware has a requirement that the ptesync must be executed on the same CPU thread as the tlbies which it is expected to order. Thus, if a vCPU gets moved from one physical CPU to another after it has done some tlbies but before it can get to do the ptesync, the ptesync will not have the desired effect when it is executed on the second physical CPU. To fix this, we do a ptesync in the exit path for radix guests. If there are any pending tlbies, this will wait for them to complete. If there aren't, then ptesync will just do the same as sync. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-17KVM: PPC: Book3S HV: XIVE: Resend re-routed interrupts on CPU priority changeBenjamin Herrenschmidt1-7/+101
When a vcpu priority (CPPR) is set to a lower value (masking more interrupts), we stop processing interrupts already in the queue for the priorities that have now been masked. If those interrupts were previously re-routed to a different CPU, they might still be stuck until the older one that has them in its queue processes them. In the case of guest CPU unplug, that can be never. To address that without creating additional overhead for the normal interrupt processing path, this changes H_CPPR handling so that when such a priority change occurs, we scan the interrupt queue for that vCPU, and for any interrupt in there that has been re-routed, we replace it with a dummy and force a re-trigger. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-17KVM: PPC: Book3S HV: Make radix clear pte when unmappingNicholas Piggin1-1/+1
The current partition table unmap code clears the _PAGE_PRESENT bit out of the pte, which leaves pud_huge/pmd_huge true and does not clear pud_present/pmd_present. This can confuse subsequent page faults and possibly lead to the guest looping doing continual hypervisor page faults. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-17KVM: PPC: Book3S HV: Make radix use correct tlbie sequence in ↵Nicholas Piggin1-2/+2
kvmppc_radix_tlbie_page The standard eieio ; tlbsync ; ptesync must follow tlbie to ensure it is ordered with respect to subsequent operations. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-17KVM: PPC: Book3S HV: Snapshot timebase offset on guest entryPaul Mackerras4-45/+47
Currently, the HV KVM guest entry/exit code adds the timebase offset from the vcore struct to the timebase on guest entry, and subtracts it on guest exit. Which is fine, except that it is possible for userspace to change the offset using the SET_ONE_REG interface while the vcore is running, as there is only one timebase offset per vcore but potentially multiple VCPUs in the vcore. If that were to happen, KVM would subtract a different offset on guest exit from that which it had added on guest entry, leading to the timebase being out of sync between cores in the host, which then leads to bad things happening such as hangs and spurious watchdog timeouts. To fix this, we add a new field 'tb_offset_applied' to the vcore struct which stores the offset that is currently applied to the timebase. This value is set from the vcore tb_offset field on guest entry, and is what is subtracted from the timebase on guest exit. Since it is zero when the timebase offset is not applied, we can simplify the logic in kvmhv_start_timing and kvmhv_accumulate_time. In addition, we had secondary threads reading the timebase while running concurrently with code on the primary thread which would eventually add or subtract the timebase offset from the timebase. This occurred while saving or restoring the DEC register value on the secondary threads. Although no specific incorrect behaviour has been observed, this is a race which should be fixed. To fix it, we move the DEC saving code to just before we call kvmhv_commence_exit, and the DEC restoring code to after the point where we have waited for the primary thread to switch the MMU context and add the timebase offset. That way we are sure that the timebase contains the guest timebase value in both cases. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-16proc: introduce proc_create_single{,_data}Christoph Hellwig3-54/+6
Variants of proc_create{,_data} that directly take a seq_file show callback and drastically reduces the boilerplate code in the callers. All trivial callers converted over. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-14misc: IBM Virtual Management Channel Driver (VMC)Bryant G. Ly1-0/+1
This driver is a logical device which provides an interface between the hypervisor and a management partition. This interface is like a message passing interface. This management partition is intended to provide an alternative to HMC-based system management. VMC enables the Management LPAR to provide basic logical partition functions: - Logical Partition Configuration - Boot, start, and stop actions for individual partitions - Display of partition status - Management of virtual Ethernet - Management of virtual Storage - Basic system management This driver is to be used for the POWER Virtual Management Channel Virtual Adapter on the PowerPC platform. It provides a character device which allows for both request/response and async message support through the /dev/ibmvmc node. Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Reviewed-by: Steven Royer <seroyer@linux.vnet.ibm.com> Reviewed-by: Adam Reznechek <adreznec@linux.vnet.ibm.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Taylor Jakobson <tjakobs@us.ibm.com> Tested-by: Brad Warrum <bwarrum@us.ibm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14softirq/powerpc: Switch to generic local_softirq_pending() implementationFrederic Weisbecker1-7/+0
Remove the ad-hoc implementation, the generic code now allows us not to reinvent the wheel. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David S. Miller <davem@davemloft.net> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Rich Felker <dalias@libc.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/1525786706-22846-9-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-09swiotlb: move the SWIOTLB config symbol to lib/KconfigChristoph Hellwig1-9/+0
This way we have one central definition of it, and user can select it as needed. The new option is not user visible, which is the behavior it had in most architectures, with a few notable exceptions: - On x86_64 and mips/loongson3 it used to be user selectable, but defaulted to y. It now is unconditional, which seems like the right thing for 64-bit architectures without guaranteed availablity of IOMMUs. - on powerpc the symbol is user selectable and defaults to n, but many boards select it. This change assumes no working setup required a manual selection, but if that turned out to be wrong we'll have to add another select statement or two for the respective boards. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-09arch: define the ARCH_DMA_ADDR_T_64BIT config symbol in lib/KconfigChristoph Hellwig1-3/+0
Define this symbol if the architecture either uses 64-bit pointers or the PHYS_ADDR_T_64BIT is set. This covers 95% of the old arch magic. We only need an additional select for Xen on ARM (why anyway?), and we now always set ARCH_DMA_ADDR_T_64BIT on mips boards with 64-bit physical addressing instead of only doing it when highmem is set. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: James Hogan <jhogan@kernel.org>
2018-05-09arch: remove the ARCH_PHYS_ADDR_T_64BIT config symbolChristoph Hellwig2-4/+2
Instead select the PHYS_ADDR_T_64BIT for 32-bit architectures that need a 64-bit phys_addr_t type directly. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: James Hogan <jhogan@kernel.org>
2018-05-09scatterlist: move the NEED_SG_DMA_LENGTH config symbol to lib/KconfigChristoph Hellwig1-3/+1
This way we have one central definition of it, and user can select it as needed. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
2018-05-09iommu-helper: move the IOMMU_HELPER config symbol to lib/Christoph Hellwig1-3/+1
This way we have one central definition of it, and user can select it as needed. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
2018-05-09iommu-helper: mark iommu_is_span_boundary as inlineChristoph Hellwig1-1/+0
This avoids selecting IOMMU_HELPER just for this function. And we only use it once or twice in normal builds so this often even is a size reduction. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-08dma-debug: remove CONFIG_HAVE_DMA_API_DEBUGChristoph Hellwig1-1/+0
There is no arch specific code required for dma-debug, so there is no need to opt into the support either. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-05-08dma-debug: move initialization to common codeChristoph Hellwig1-3/+0
Most mainstream architectures are using 65536 entries, so lets stick to that. If someone is really desperate to override it that can still be done through <asm/dma-mapping.h>, but I'd rather see a really good rationale for that. dma_debug_init is now called as a core_initcall, which for many architectures means much earlier, and provides dma-debug functionality earlier in the boot process. This should be safe as it only relies on the memory allocator already being available. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-05-08powerpc/pseries: Fix CONFIG_NUMA=n buildMichael Ellerman1-8/+5
The build is failing with CONFIG_NUMA=n and some compiler versions: arch/powerpc/platforms/pseries/hotplug-cpu.o: In function `dlpar_online_cpu': hotplug-cpu.c:(.text+0x12c): undefined reference to `timed_topology_update' arch/powerpc/platforms/pseries/hotplug-cpu.o: In function `dlpar_cpu_remove': hotplug-cpu.c:(.text+0x400): undefined reference to `timed_topology_update' Fix it by moving the empty version of timed_topology_update() into the existing #ifdef block, which has the right guard of SPLPAR && NUMA. Fixes: cee5405da402 ("powerpc/hotplug: Improve responsiveness of hotplug change") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-07powerpc/trace/syscalls: Update syscall name matching logic to account for ↵Naveen N. Rao1-2/+19
ppc_ prefix Some syscall entry functions on powerpc are prefixed with ppc_/ppc32_/ppc64_ rather than the usual sys_/__se_sys prefix. fork(), clone(), swapcontext() are some examples of syscalls with such entry points. We need to match against these names when initializing ftrace syscall tracing. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-07powerpc/trace/syscalls: Update syscall name matching logicNaveen N. Rao1-7/+3
On powerpc64 ABIv1, we are enabling syscall tracing for only ~20 syscalls. This is due to commit e145242ea0df6 ("syscalls/core, syscalls/x86: Clean up syscall stub naming convention") which has changed the syscall entry wrapper prefix from "SyS" to "__se_sys". Update the logic for ABIv1 to not just skip the initial dot, but also the "__se_sys" prefix. Fixes: commit e145242ea0df6 ("syscalls/core, syscalls/x86: Clean up syscall stub naming convention") Reported-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-07powerpc/64: Remove unused paca->soft_enabledMichael Ellerman1-1/+0
In commit 4e26bc4a4ed6 ("powerpc/64: Rename soft_enabled to irq_soft_mask") we renamed paca->soft_enabled. But then in commit 8e0b634b1327 ("powerpc/64s: Do not allocate lppaca if we are not virtualized") we added it back. Oops. This happened because the two patches were in flight at the same time and rebased vs each other multiple times, and we missed it in review. Fixes: 8e0b634b1327 ("powerpc/64s: Do not allocate lppaca if we are not virtualized") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-07PCI: remove PCI_DMA_BUS_IS_PHYSChristoph Hellwig1-18/+0
This was used by the ide, scsi and networking code in the past to determine if they should bounce payloads. Now that the dma mapping always have to support dma to all physical memory (thanks to swiotlb for non-iommu systems) there is no need to this crude hack any more. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Palmer Dabbelt <palmer@sifive.com> (for riscv) Reviewed-by: Jens Axboe <axboe@kernel.dk>
2018-05-02Merge branch 'timers/urgent' into timers/coreThomas Gleixner14-53/+153
Pick up urgent fixes to apply dependent cleanup patch
2018-04-28Merge tag 'v4.17-rc2' into docs-nextJonathan Corbet6-5/+21
Merge -rc2 to pick up the changes to Documentation/core-api/kernel-api.rst that hit mainline via the networking tree. In their absence, subsequent patches cannot be applied.
2018-04-27powerpc/kvm/booke: Fix altivec related build breakLaurentiu Tudor1-0/+7
Add missing "altivec unavailable" interrupt injection helper thus fixing the linker error below: arch/powerpc/kvm/emulate_loadstore.o: In function `kvmppc_check_altivec_disabled': arch/powerpc/kvm/emulate_loadstore.c: undefined reference to `.kvmppc_core_queue_vec_unavail' Fixes: 09f984961c137c4b ("KVM: PPC: Book3S: Add MMIO emulation for VMX instructions") Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-27powerpc: Fix deadlock with multiple calls to smp_send_stopNicholas Piggin1-16/+39
smp_send_stop can lock up the IPI path for any subsequent calls, because the receiving CPUs spin in their handler function. This started becoming a problem with the addition of an smp_send_stop call in the reboot path, because panics can reboot after doing their own smp_send_stop. The NMI IPI variant was fixed with ac61c11566 ("powerpc: Fix smp_send_stop NMI IPI handling"), which leaves the smp_call_function variant. This is fixed by having smp_send_stop only ever do the smp_call_function once. This is a bit less robust than the NMI IPI fix, because any other call to smp_call_function after smp_send_stop could deadlock, but that has always been the case, and it was not been a problem before. Fixes: f2748bdfe1573 ("powerpc/powernv: Always stop secondaries before reboot/shutdown") Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-25signal/powerpc: Replace TRAP_FIXME with TRAP_UNKEric W. Biederman2-10/+2
Using an si_code of 0 that aliases with SI_USER is clearly the wrong thing todo, and causes problems in interesting ways. For use in unknown_exception the recently defined TRAP_UNK semantically is a perfect fit. For use in RunModeException it looks like something more specific than TRAP_UNK could be used. No one has bothered to find a better fit than the broken si_code of 0 in all of these years and I don't see an obvious better fit so TRAP_UNK is switching RunModeException to return TRAP_UNK is clearly an improvement. Recent history suggests no actually cares about crazy corner cases of the kernel behavior like this so I don't expect any regressions from changing this. However if something does happen this change is easy to revert. Though I wonder if SIGKILL might not be a better fit. Cc: Paul Mackerras <paulus@samba.org> Cc: Kumar Gala <kumar.gala@freescale.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: linuxppc-dev@lists.ozlabs.org Fixes: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx") Fixes: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25signal/powerpc: Replace FPE_FIXME with FPE_FLTUNKEric W. Biederman2-10/+3
Using an si_code of 0 that aliases with SI_USER is clearly the wrong thing todo, and causes problems in interesting ways. The newly defined FPE_FLTUNK semantically appears to fit the bill so use it instead. Cc: Paul Mackerras <paulus@samba.org> Cc: Kumar Gala <kumar.gala@freescale.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: linuxppc-dev@lists.ozlabs.org Fixes: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx") Fixes: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25signal: Ensure every siginfo we send has all bits initializedEric W. Biederman4-3/+4
Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions. Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure. The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized. In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared. Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25powerpc: Fix smp_send_stop NMI IPI handlingNicholas Piggin1-5/+17
The NMI IPI handler for a receiving CPU increments nmi_ipi_busy_count over the handler function call, which causes later smp_send_nmi_ipi() callers to spin until the call is finished. The stop_this_cpu() function never returns, so the busy count is never decremeted, which can cause the system to hang in some cases. For example panic() will call smp_send_stop() early on which calls stop_this_cpu() on other CPUs, then later in the reboot path, pnv_restart() will call smp_send_stop() again, which hangs. Fix this by adding a special case to the stop_this_cpu() handler to decrement the busy count, because it will never return. Now that the NMI/non-NMI versions of stop_this_cpu() are different, split them out into separate functions rather than doing #ifdef tricks to share the body between the two functions. Fixes: 6bed3237624e3 ("powerpc: use NMI IPI for smp_send_stop") Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Split out the functions, tweak change log a bit] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-25rtc: opal: Fix OPAL RTC driver OPAL_BUSY loopsNicholas Piggin1-3/+5
The OPAL RTC driver does not sleep in case it gets OPAL_BUSY or OPAL_BUSY_EVENT from firmware, which causes large scheduling latencies, up to 50 seconds have been observed here when RTC stops responding (BMC reboot can do it). Fix this by converting it to the standard form OPAL_BUSY loop that sleeps. Fixes: 628daa8d5abf ("powerpc/powernv: Add RTC and NVRAM support plus RTAS fallbacks") Cc: stable@vger.kernel.org # v3.2+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-24powerpc/mce: Fix a bug where mce loops on memory UE.Mahesh Salgaonkar1-5/+2
The current code extracts the physical address for UE errors and then hooks it up into memory failure infrastructure. On successful extraction of physical address it wrongly sets "handled = 1" which means this UE error has been recovered. Since MCE handler gets return value as handled = 1, it assumes that error has been recovered and goes back to same NIP. This causes MCE interrupt again and again in a loop leading to hard lockup. Also, initialize phys_addr to ULONG_MAX so that we don't end up queuing undesired page to hwpoison. Without this patch we see: Severe Machine check interrupt [Recovered] NIP: [000000001002588c] PID: 7109 Comm: find Initiator: CPU Error type: UE [Load/Store] Effective address: 00007fffd2755940 Physical address: 000020181a080000 ... Severe Machine check interrupt [Recovered] NIP: [000000001002588c] PID: 7109 Comm: find Initiator: CPU Error type: UE [Load/Store] Effective address: 00007fffd2755940 Physical address: 000020181a080000 Severe Machine check interrupt [Recovered] NIP: [000000001002588c] PID: 7109 Comm: find Initiator: CPU Error type: UE [Load/Store] Effective address: 00007fffd2755940 Physical address: 000020181a080000 Memory failure: 0x20181a08: recovery action for dirty LRU page: Recovered Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned ... Watchdog CPU:38 Hard LOCKUP After this patch we see: Severe Machine check interrupt [Not recovered] NIP: [00007fffaae585f4] PID: 7168 Comm: find Initiator: CPU Error type: UE [Load/Store] Effective address: 00007fffaafe28ac Physical address: 00002017c0bd0000 find[7168]: unhandled signal 7 at 00007fffaae585f4 nip 00007fffaae585f4 lr 00007fffaae585e0 code 4 Memory failure: 0x2017c0bd: recovery action for dirty LRU page: Recovered Fixes: 01eaac2b0591 ("powerpc/mce: Hookup ierror (instruction) UE errors") Fixes: ba41e1e1ccb9 ("powerpc/mce: Hookup derror (load/store) UE errors") Cc: stable@vger.kernel.org # v4.15+ Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-24powerpc/powernv/npu: Do a PID GPU TLB flush when invalidating a large ↵Alistair Popple1-4/+19
address range The NPU has a limited number of address translation shootdown (ATSD) registers and the GPU has limited bandwidth to process ATSDs. This can result in contention of ATSD registers leading to soft lockups on some threads, particularly when invalidating a large address range in pnv_npu2_mn_invalidate_range(). At some threshold it becomes more efficient to flush the entire GPU TLB for the given MM context (PID) than individually flushing each address in the range. This patch will result in ranges greater than 2MB being converted from 32+ ATSDs into a single ATSD which will flush the TLB for the given PID on each GPU. Fixes: 1ab66d1fbada ("powerpc/powernv: Introduce address translation services for Nvlink2") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Alistair Popple <alistair@popple.id.au> Acked-by: Balbir Singh <bsingharora@gmail.com> Tested-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-24powerpc/powernv/npu: Prevent overwriting of pnv_npu2_init_contex() callback ↵Alistair Popple2-4/+14
parameters There is a single npu context per set of callback parameters. Callers should be prevented from overwriting existing callback values so instead return an error if different parameters are passed. Fixes: 1ab66d1fbada ("powerpc/powernv: Introduce address translation services for Nvlink2") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Alistair Popple <alistair@popple.id.au> Reviewed-by: Mark Hairgrove <mhairgrove@nvidia.com> Tested-by: Mark Hairgrove <mhairgrove@nvidia.com> Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-24powerpc/powernv/npu: Add lock to prevent race in concurrent context init/destroyAlistair Popple1-9/+42
The pnv_npu2_init_context() and pnv_npu2_destroy_context() functions are used to allocate/free contexts to allow address translation and shootdown by the NPU on a particular GPU. Context initialisation is implicitly safe as it is protected by the requirement mmap_sem be held in write mode, however pnv_npu2_destroy_context() does not require mmap_sem to be held and it is not safe to call with a concurrent initialisation for a different GPU. It was assumed the driver would ensure destruction was not called concurrently with initialisation. However the driver may be simplified by allowing concurrent initialisation and destruction for different GPUs. As npu context creation/destruction is not a performance critical path and the critical section is not large a single spinlock is used for simplicity. Fixes: 1ab66d1fbada ("powerpc/powernv: Introduce address translation services for Nvlink2") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Alistair Popple <alistair@popple.id.au> Reviewed-by: Mark Hairgrove <mhairgrove@nvidia.com> Tested-by: Mark Hairgrove <mhairgrove@nvidia.com> Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>