wireguard-linux/arch/arm64/include/asm, branch jd/orphan-parallel

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

2020-10-23T18:17:56Z

Pull KVM updates from Paolo Bonzini: "For x86, there is a new alternative and (in the future) more scalable implementation of extended page tables that does not need a reverse map from guest physical addresses to host physical addresses. For now it is disabled by default because it is still lacking a few of the existing MMU's bells and whistles. However it is a very solid piece of work and it is already available for people to hammer on it. Other updates: ARM: - New page table code for both hypervisor and guest stage-2 - Introduction of a new EL2-private host context - Allow EL2 to have its own private per-CPU variables - Support of PMU event filtering - Complete rework of the Spectre mitigation PPC: - Fix for running nested guests with in-kernel IRQ chip - Fix race condition causing occasional host hard lockup - Minor cleanups and bugfixes x86: - allow trapping unknown MSRs to userspace - allow userspace to force #GP on specific MSRs - INVPCID support on AMD - nested AMD cleanup, on demand allocation of nested SVM state - hide PV MSRs and hypercalls for features not enabled in CPUID - new test for MSR_IA32_TSC writes from host and guest - cleanups: MMU, CPUID, shared MSRs - LAPIC latency optimizations ad bugfixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (232 commits) kvm: x86/mmu: NX largepage recovery for TDP MMU kvm: x86/mmu: Don't clear write flooding count for direct roots kvm: x86/mmu: Support MMIO in the TDP MMU kvm: x86/mmu: Support write protection for nesting in tdp MMU kvm: x86/mmu: Support disabling dirty logging for the tdp MMU kvm: x86/mmu: Support dirty logging for the TDP MMU kvm: x86/mmu: Support changed pte notifier in tdp MMU kvm: x86/mmu: Add access tracking for tdp_mmu kvm: x86/mmu: Support invalidate range MMU notifier for TDP MMU kvm: x86/mmu: Allocate struct kvm_mmu_pages for all pages in TDP MMU kvm: x86/mmu: Add TDP MMU PF handler kvm: x86/mmu: Remove disallowed_hugepage_adjust shadow_walk_iterator arg kvm: x86/mmu: Support zapping SPTEs in the TDP MMU KVM: Cache as_id in kvm_memory_slot kvm: x86/mmu: Add functions to handle changed TDP SPTEs kvm: x86/mmu: Allocate and free TDP MMU roots kvm: x86/mmu: Init / Uninit the TDP MMU kvm: x86/mmu: Introduce tdp_iter KVM: mmu: extract spte.h and spte.c KVM: mmu: Separate updating a PTE from kvm_set_pte_rmapp ...

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2020-10-23T16:46:16Z

Pull more arm64 updates from Will Deacon: "A small selection of further arm64 fixes and updates. Most of these are fixes that came in during the merge window, with the exception of the HAVE_MOVE_PMD mremap() speed-up which we discussed back in 2018 and somehow forgot to enable upstream. - Improve performance of Spectre-v2 mitigation on Falkor CPUs (if you're lucky enough to have one) - Select HAVE_MOVE_PMD. This has been shown to improve mremap() performance, which is used heavily by the Android runtime GC, and it seems we forgot to enable this upstream back in 2018. - Ensure linker flags are consistent between LLVM and BFD - Fix stale comment in Spectre mitigation rework - Fix broken copyright header - Fix KASLR randomisation of the linear map - Prevent arm64-specific prctl()s from compat tasks (return -EINVAL)" Link: https://lore.kernel.org/kvmarm/20181108181201.88826-3-joelaf@google.com/ * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: proton-pack: Update comment to reflect new function name arm64: spectre-v2: Favour CPU-specific mitigation at EL2 arm64: link with -z norelro regardless of CONFIG_RELOCATABLE arm64: Fix a broken copyright header in gen_vdso_offsets.sh arm64: mremap speedup - Enable HAVE_MOVE_PMD arm64: mm: use single quantity to represent the PA to VA translation arm64: reject prctl(PR_PAC_RESET_KEYS) on compat tasks

Merge tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2020-10-22T20:13:57Z

Pull Kbuild updates from Masahiro Yamada: - Support 'make compile_commands.json' to generate the compilation database more easily, avoiding stale entries - Support 'make clang-analyzer' and 'make clang-tidy' for static checks using clang-tidy - Preprocess scripts/modules.lds.S to allow CONFIG options in the module linker script - Drop cc-option tests from compiler flags supported by our minimal GCC/Clang versions - Use always 12-digits commit hash for CONFIG_LOCALVERSION_AUTO=y - Use sha1 build id for both BFD linker and LLD - Improve deb-pkg for reproducible builds and rootless builds - Remove stale, useless scripts/namespace.pl - Turn -Wreturn-type warning into error - Fix build error of deb-pkg when CONFIG_MODULES=n - Replace 'hostname' command with more portable 'uname -n' - Various Makefile cleanups * tag 'kbuild-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits) kbuild: Use uname for LINUX_COMPILE_HOST detection kbuild: Only add -fno-var-tracking-assignments for old GCC versions kbuild: remove leftover comment for filechk utility treewide: remove DISABLE_LTO kbuild: deb-pkg: clean up package name variables kbuild: deb-pkg: do not build linux-headers package if CONFIG_MODULES=n kbuild: enforce -Werror=return-type scripts: remove namespace.pl builddeb: Add support for all required debian/rules targets builddeb: Enable rootless builds builddeb: Pass -n to gzip for reproducible packages kbuild: split the build log of kallsyms kbuild: explicitly specify the build id style scripts/setlocalversion: make git describe output more reliable kbuild: remove cc-option test of -Werror=date-time kbuild: remove cc-option test of -fno-stack-check kbuild: remove cc-option test of -fno-strict-overflow kbuild: move CFLAGS_{KASAN,UBSAN,KCSAN} exports to relevant Makefiles kbuild: remove redundant CONFIG_KASAN check from scripts/Makefile.kasan kbuild: do not create built-in objects for external module builds ...

Merge tag 'kvmarm-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2020-10-20T12:14:25Z

KVM/arm64 updates for Linux 5.10 - New page table code for both hypervisor and guest stage-2 - Introduction of a new EL2-private host context - Allow EL2 to have its own private per-CPU variables - Support of PMU event filtering - Complete rework of the Spectre mitigation

mm/madvise: introduce process_madvise() syscall: an external memory hinting API

2020-10-18T16:27:10Z

There is usecase that System Management Software(SMS) want to give a memory hint like MADV_[COLD|PAGEEOUT] to other processes and in the case of Android, it is the ActivityManagerService. The information required to make the reclaim decision is not known to the app. Instead, it is known to the centralized userspace daemon(ActivityManagerService), and that daemon must be able to initiate reclaim on its own without any app involvement. To solve the issue, this patch introduces a new syscall process_madvise(2). It uses pidfd of an external process to give the hint. It also supports vector address range because Android app has thousands of vmas due to zygote so it's totally waste of CPU and power if we should call the syscall one by one for each vma.(With testing 2000-vma syscall vs 1-vector syscall, it showed 15% performance improvement. I think it would be bigger in real practice because the testing ran very cache friendly environment). Another potential use case for the vector range is to amortize the cost ofTLB shootdowns for multiple ranges when using MADV_DONTNEED; this could benefit users like TCP receive zerocopy and malloc implementations. In future, we could find more usecases for other advises so let's make it happens as API since we introduce a new syscall at this moment. With that, existing madvise(2) user could replace it with process_madvise(2) with their own pid if they want to have batch address ranges support feature. ince it could affect other process's address range, only privileged process(PTRACE_MODE_ATTACH_FSCREDS) or something else(e.g., being the same UID) gives it the right to ptrace the process could use it successfully. The flag argument is reserved for future use if we need to extend the API. I think supporting all hints madvise has/will supported/support to process_madvise is rather risky. Because we are not sure all hints make sense from external process and implementation for the hint may rely on the caller being in the current context so it could be error-prone. Thus, I just limited hints as MADV_[COLD|PAGEOUT] in this patch. If someone want to add other hints, we could hear the usecase and review it for each hint. It's safer for maintenance rather than introducing a buggy syscall but hard to fix it later. So finally, the API is as follows, ssize_t process_madvise(int pidfd, const struct iovec *iovec, unsigned long vlen, int advice, unsigned int flags); DESCRIPTION The process_madvise() system call is used to give advice or directions to the kernel about the address ranges from external process as well as local process. It provides the advice to address ranges of process described by iovec and vlen. The goal of such advice is to improve system or application performance. The pidfd selects the process referred to by the PID file descriptor specified in pidfd. (See pidofd_open(2) for further information) The pointer iovec points to an array of iovec structures, defined in as: struct iovec { void *iov_base; /* starting address */ size_t iov_len; /* number of bytes to be advised */ }; The iovec describes address ranges beginning at address(iov_base) and with size length of bytes(iov_len). The vlen represents the number of elements in iovec. The advice is indicated in the advice argument, which is one of the following at this moment if the target process specified by pidfd is external. MADV_COLD MADV_PAGEOUT Permission to provide a hint to external process is governed by a ptrace access mode PTRACE_MODE_ATTACH_FSCREDS check; see ptrace(2). The process_madvise supports every advice madvise(2) has if target process is in same thread group with calling process so user could use process_madvise(2) to extend existing madvise(2) to support vector address ranges. RETURN VALUE On success, process_madvise() returns the number of bytes advised. This return value may be less than the total number of requested bytes, if an error occurred. The caller should check return value to determine whether a partial advice occurred. FAQ: Q.1 - Why does any external entity have better knowledge? Quote from Sandeep "For Android, every application (including the special SystemServer) are forked from Zygote. The reason of course is to share as many libraries and classes between the two as possible to benefit from the preloading during boot. After applications start, (almost) all of the APIs end up calling into this SystemServer process over IPC (binder) and back to the application. In a fully running system, the SystemServer monitors every single process periodically to calculate their PSS / RSS and also decides which process is "important" to the user for interactivity. So, because of how these processes start _and_ the fact that the SystemServer is looping to monitor each process, it does tend to *know* which address range of the application is not used / useful. Besides, we can never rely on applications to clean things up themselves. We've had the "hey app1, the system is low on memory, please trim your memory usage down" notifications for a long time[1]. They rely on applications honoring the broadcasts and very few do. So, if we want to avoid the inevitable killing of the application and restarting it, some way to be able to tell the OS about unimportant memory in these applications will be useful. - ssp Q.2 - How to guarantee the race(i.e., object validation) between when giving a hint from an external process and get the hint from the target process? process_madvise operates on the target process's address space as it exists at the instant that process_madvise is called. If the space target process can run between the time the process_madvise process inspects the target process address space and the time that process_madvise is actually called, process_madvise may operate on memory regions that the calling process does not expect. It's the responsibility of the process calling process_madvise to close this race condition. For example, the calling process can suspend the target process with ptrace, SIGSTOP, or the freezer cgroup so that it doesn't have an opportunity to change its own address space before process_madvise is called. Another option is to operate on memory regions that the caller knows a priori will be unchanged in the target process. Yet another option is to accept the race for certain process_madvise calls after reasoning that mistargeting will do no harm. The suggested API itself does not provide synchronization. It also apply other APIs like move_pages, process_vm_write. The race isn't really a problem though. Why is it so wrong to require that callers do their own synchronization in some manner? Nobody objects to write(2) merely because it's possible for two processes to open the same file and clobber each other's writes --- instead, we tell people to use flock or something. Think about mmap. It never guarantees newly allocated address space is still valid when the user tries to access it because other threads could unmap the memory right before. That's where we need synchronization by using other API or design from userside. It shouldn't be part of API itself. If someone needs more fine-grained synchronization rather than process level, there were two ideas suggested - cookie[2] and anon-fd[3]. Both are applicable via using last reserved argument of the API but I don't think it's necessary right now since we have already ways to prevent the race so don't want to add additional complexity with more fine-grained optimization model. To make the API extend, it reserved an unsigned long as last argument so we could support it in future if someone really needs it. Q.3 - Why doesn't ptrace work? Injecting an madvise in the target process using ptrace would not work for us because such injected madvise would have to be executed by the target process, which means that process would have to be runnable and that creates the risk of the abovementioned race and hinting a wrong VMA. Furthermore, we want to act the hint in caller's context, not the callee's, because the callee is usually limited in cpuset/cgroups or even freezed state so they can't act by themselves quick enough, which causes more thrashing/kill. It doesn't work if the target process are ptraced(e.g., strace, debugger, minidump) because a process can have at most one ptracer. [1] https://developer.android.com/topic/performance/memory" [2] process_getinfo for getting the cookie which is updated whenever vma of process address layout are changed - Daniel Colascione - https://lore.kernel.org/lkml/20190520035254.57579-1-minchan@kernel.org/T/#m7694416fd179b2066a2c62b5b139b14e3894e224 [3] anonymous fd which is used for the object(i.e., address range) validation - Michal Hocko - https://lore.kernel.org/lkml/20200120112722.GY18451@dhcp22.suse.cz/ [minchan@kernel.org: fix process_madvise build break for arm64] Link: http://lkml.kernel.org/r/20200303145756.GA219683@google.com [minchan@kernel.org: fix build error for mips of process_madvise] Link: http://lkml.kernel.org/r/20200508052517.GA197378@google.com [akpm@linux-foundation.org: fix patch ordering issue] [akpm@linux-foundation.org: fix arm64 whoops] [minchan@kernel.org: make process_madvise() vlen arg have type size_t, per Florian] [akpm@linux-foundation.org: fix i386 build] [sfr@canb.auug.org.au: fix syscall numbering] Link: https://lkml.kernel.org/r/20200905142639.49fc3f1a@canb.auug.org.au [sfr@canb.auug.org.au: madvise.c needs compat.h] Link: https://lkml.kernel.org/r/20200908204547.285646b4@canb.auug.org.au [minchan@kernel.org: fix mips build] Link: https://lkml.kernel.org/r/20200909173655.GC2435453@google.com [yuehaibing@huawei.com: remove duplicate header which is included twice] Link: https://lkml.kernel.org/r/20200915121550.30584-1-yuehaibing@huawei.com [minchan@kernel.org: do not use helper functions for process_madvise] Link: https://lkml.kernel.org/r/20200921175539.GB387368@google.com [akpm@linux-foundation.org: pidfd_get_pid() gained an argument] [sfr@canb.auug.org.au: fix up for "iov_iter: transparently handle compat iovecs in import_iovec"] Link: https://lkml.kernel.org/r/20200928212542.468e1fef@canb.auug.org.au Signed-off-by: Minchan Kim Signed-off-by: YueHaibing Signed-off-by: Stephen Rothwell Signed-off-by: Andrew Morton Reviewed-by: Suren Baghdasaryan Reviewed-by: Vlastimil Babka Acked-by: David Rientjes Cc: Alexander Duyck Cc: Brian Geffon Cc: Christian Brauner Cc: Daniel Colascione Cc: Jann Horn Cc: Jens Axboe Cc: Joel Fernandes Cc: Johannes Weiner Cc: John Dias Cc: Kirill Tkhai Cc: Michal Hocko Cc: Oleksandr Natalenko Cc: Sandeep Patil Cc: SeongJae Park Cc: SeongJae Park Cc: Shakeel Butt Cc: Sonny Rao Cc: Tim Murray Cc: Christian Brauner Cc: Florian Weimer Cc: Link: http://lkml.kernel.org/r/20200302193630.68771-3-minchan@kernel.org Link: http://lkml.kernel.org/r/20200508183320.GA125527@google.com Link: http://lkml.kernel.org/r/20200622192900.22757-4-minchan@kernel.org Link: https://lkml.kernel.org/r/20200901000633.1920247-4-minchan@kernel.org Signed-off-by: Linus Torvalds

arm64: mm: use single quantity to represent the PA to VA translation

2020-10-15T10:14:57Z

On arm64, the global variable memstart_addr represents the physical address of PAGE_OFFSET, and so physical to virtual translations or vice versa used to come down to simple additions or subtractions involving the values of PAGE_OFFSET and memstart_addr. When support for 52-bit virtual addressing was introduced, we had to deal with PAGE_OFFSET potentially being outside of the region that can be covered by the virtual range (as the 52-bit VA capable build needs to be able to run on systems that are only 48-bit VA capable), and for this reason, another translation was introduced, and recorded in the global variable physvirt_offset. However, if we go back to the original definition of memstart_addr, i.e., the physical address of PAGE_OFFSET, it turns out that there is no need for two separate translations: instead, we can simply subtract the size of the unaddressable VA space from memstart_addr to make the available physical memory appear in the 48-bit addressable VA region. This simplifies things, but also fixes a bug on KASLR builds, which may update memstart_addr later on in arm64_memblock_init(), but fails to update vmemmap and physvirt_offset accordingly. Fixes: 5383cc6efed1 ("arm64: mm: Introduce vabits_actual") Signed-off-by: Ard Biesheuvel Reviewed-by: Steve Capper Link: https://lore.kernel.org/r/20201008153602.9467-2-ardb@kernel.org Signed-off-by: Will Deacon

Merge tag 'iommu-updates-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

2020-10-14T19:08:34Z

Pull iommu updates from Joerg Roedel: - ARM-SMMU Updates from Will: - Continued SVM enablement, where page-table is shared with CPU - Groundwork to support integrated SMMU with Adreno GPU - Allow disabling of MSI-based polling on the kernel command-line - Minor driver fixes and cleanups (octal permissions, error messages, ...) - Secure Nested Paging Support for AMD IOMMU. The IOMMU will fault when a device tries DMA on memory owned by a guest. This needs new fault-types as well as a rewrite of the IOMMU memory semaphore for command completions. - Allow broken Intel IOMMUs (wrong address widths reported) to still be used for interrupt remapping. - IOMMU UAPI updates for supporting vSVA, where the IOMMU can access address spaces of processes running in a VM. - Support for the MT8167 IOMMU in the Mediatek IOMMU driver. - Device-tree updates for the Renesas driver to support r8a7742. - Several smaller fixes and cleanups all over the place. * tag 'iommu-updates-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (57 commits) iommu/vt-d: Gracefully handle DMAR units with no supported address widths iommu/vt-d: Check UAPI data processed by IOMMU core iommu/uapi: Handle data and argsz filled by users iommu/uapi: Rename uapi functions iommu/uapi: Use named union for user data iommu/uapi: Add argsz for user filled data docs: IOMMU user API iommu/qcom: add missing put_device() call in qcom_iommu_of_xlate() iommu/arm-smmu-v3: Add SVA device feature iommu/arm-smmu-v3: Check for SVA features iommu/arm-smmu-v3: Seize private ASID iommu/arm-smmu-v3: Share process page tables iommu/arm-smmu-v3: Move definitions to a header iommu/io-pgtable-arm: Move some definitions to a header iommu/arm-smmu-v3: Ensure queue is read after updating prod pointer iommu/amd: Re-purpose Exclusion range registers to support SNP CWWB iommu/amd: Add support for RMP_PAGE_FAULT and RMP_HW_ERR iommu/amd: Use 4K page for completion wait write-back semaphore iommu/tegra-smmu: Allow to group clients in same swgroup iommu/tegra-smmu: Fix iova->phys translation ...

Merge tag 'pm-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2020-10-14T17:45:41Z

Pull power management updates from Rafael Wysocki: "These rework the collection of cpufreq statistics to allow it to take place if fast frequency switching is enabled in the governor, rework the frequency invariance handling in the cpufreq core and drivers, add new hardware support to a couple of cpufreq drivers, fix a number of assorted issues and clean up the code all over. Specifics: - Rework cpufreq statistics collection to allow it to take place when fast frequency switching is enabled in the governor (Viresh Kumar). - Make the cpufreq core set the frequency scale on behalf of the driver and update several cpufreq drivers accordingly (Ionela Voinescu, Valentin Schneider). - Add new hardware support to the STI and qcom cpufreq drivers and improve them (Alain Volmat, Manivannan Sadhasivam). - Fix multiple assorted issues in cpufreq drivers (Jon Hunter, Krzysztof Kozlowski, Matthias Kaehlcke, Pali Rohár, Stephan Gerhold, Viresh Kumar). - Fix several assorted issues in the operating performance points (OPP) framework (Stephan Gerhold, Viresh Kumar). - Allow devfreq drivers to fetch devfreq instances by DT enumeration instead of using explicit phandles and modify the devfreq core code to support driver-specific devfreq DT bindings (Leonard Crestez, Chanwoo Choi). - Improve initial hardware resetting in the tegra30 devfreq driver and clean up the tegra cpuidle driver (Dmitry Osipenko). - Update the cpuidle core to collect state entry rejection statistics and expose them via sysfs (Lina Iyer). - Improve the ACPI _CST code handling diagnostics (Chen Yu). - Update the PSCI cpuidle driver to allow the PM domain initialization to occur in the OSI mode as well as in the PC mode (Ulf Hansson). - Rework the generic power domains (genpd) core code to allow domain power off transition to be aborted in the absence of the "power off" domain callback (Ulf Hansson). - Fix two suspend-to-idle issues in the ACPI EC driver (Rafael Wysocki). - Fix the handling of timer_expires in the PM-runtime framework on 32-bit systems and the handling of device links in it (Grygorii Strashko, Xiang Chen). - Add IO requests batching support to the hibernate image saving and reading code and drop a bogus get_gendisk() from there (Xiaoyi Chen, Christoph Hellwig). - Allow PCIe ports to be put into the D3cold power state if they are power-manageable via ACPI (Lukas Wunner). - Add missing header file include to a power capping driver (Pujin Shi). - Clean up the qcom-cpr AVS driver a bit (Liu Shixin). - Kevin Hilman steps down as designated reviwer of adaptive voltage scaling (AVS) drivers (Kevin Hilman)" * tag 'pm-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (65 commits) cpufreq: stats: Fix string format specifier mismatch arm: disable frequency invariance for CONFIG_BL_SWITCHER cpufreq,arm,arm64: restructure definitions of arch_set_freq_scale() cpufreq: stats: Add memory barrier to store_reset() cpufreq: schedutil: Simplify sugov_fast_switch() ACPI: EC: PM: Drop ec_no_wakeup check from acpi_ec_dispatch_gpe() ACPI: EC: PM: Flush EC work unconditionally after wakeup PCI/ACPI: Whitelist hotplug ports for D3 if power managed by ACPI PM: hibernate: remove the bogus call to get_gendisk() in software_resume() cpufreq: Move traces and update to policy->cur to cpufreq core cpufreq: stats: Enable stats for fast-switch as well cpufreq: stats: Mark few conditionals with unlikely() cpufreq: stats: Remove locking cpufreq: stats: Defer stats update to cpufreq_stats_record_transition() PM: domains: Allow to abort power off when no ->power_off() callback PM: domains: Rename power state enums for genpd PM / devfreq: tegra30: Improve initial hardware resetting PM / devfreq: event: Change prototype of devfreq_event_get_edev_by_phandle function PM / devfreq: Change prototype of devfreq_get_devfreq_by_phandle function PM / devfreq: Add devfreq_get_devfreq_by_node function ...

Merge tag 'for-linus-5.10b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2020-10-14T17:34:45Z

Pull xen updates from Juergen Gross: - two small cleanup patches - avoid error messages when initializing MCA banks in a Xen dom0 - a small series for converting the Xen gntdev driver to use pin_user_pages*() instead of get_user_pages*() - intermediate fix for running as a Xen guest on Arm with KPTI enabled (the final solution will need new Xen functionality) * tag 'for-linus-5.10b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: Fix typo in xen_pagetable_p2m_free() x86/xen: disable Firmware First mode for correctable memory errors xen/arm: do not setup the runstate info page if kpti is enabled xen: remove redundant initialization of variable ret xen/gntdev.c: Convert get_user_pages*() to pin_user_pages*() xen/gntdev.c: Mark pages as dirty

Merge branch 'compat.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2020-10-12T23:44:57Z

Pull compat mount cleanups from Al Viro: "The last remnants of mount(2) compat buried by Christoph. Buried into NFS, that is. Generally I'm less enthusiastic about "let's use in_compat_syscall() deep in call chain" kind of approach than Christoph seems to be, but in this case it's warranted - that had been an NFS-specific wart, hopefully not to be repeated in any other filesystems (read: any new filesystem introducing non-text mount options will get NAKed even if it doesn't mess the layout up). IOW, not worth trying to grow an infrastructure that would avoid that use of in_compat_syscall()..." * 'compat.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: remove compat_sys_mount fs,nfs: lift compat nfs4 mount data handling into the nfs code nfs: simplify nfs4_parse_monolithic