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2022-12-15Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-6/+6
Pull kvm updates from Paolo Bonzini: "ARM64: - Enable the per-vcpu dirty-ring tracking mechanism, together with an option to keep the good old dirty log around for pages that are dirtied by something other than a vcpu. - Switch to the relaxed parallel fault handling, using RCU to delay page table reclaim and giving better performance under load. - Relax the MTE ABI, allowing a VMM to use the MAP_SHARED mapping option, which multi-process VMMs such as crosvm rely on (see merge commit 382b5b87a97d: "Fix a number of issues with MTE, such as races on the tags being initialised vs the PG_mte_tagged flag as well as the lack of support for VM_SHARED when KVM is involved. Patches from Catalin Marinas and Peter Collingbourne"). - Merge the pKVM shadow vcpu state tracking that allows the hypervisor to have its own view of a vcpu, keeping that state private. - Add support for the PMUv3p5 architecture revision, bringing support for 64bit counters on systems that support it, and fix the no-quite-compliant CHAIN-ed counter support for the machines that actually exist out there. - Fix a handful of minor issues around 52bit VA/PA support (64kB pages only) as a prefix of the oncoming support for 4kB and 16kB pages. - Pick a small set of documentation and spelling fixes, because no good merge window would be complete without those. s390: - Second batch of the lazy destroy patches - First batch of KVM changes for kernel virtual != physical address support - Removal of a unused function x86: - Allow compiling out SMM support - Cleanup and documentation of SMM state save area format - Preserve interrupt shadow in SMM state save area - Respond to generic signals during slow page faults - Fixes and optimizations for the non-executable huge page errata fix. - Reprogram all performance counters on PMU filter change - Cleanups to Hyper-V emulation and tests - Process Hyper-V TLB flushes from a nested guest (i.e. from a L2 guest running on top of a L1 Hyper-V hypervisor) - Advertise several new Intel features - x86 Xen-for-KVM: - Allow the Xen runstate information to cross a page boundary - Allow XEN_RUNSTATE_UPDATE flag behaviour to be configured - Add support for 32-bit guests in SCHEDOP_poll - Notable x86 fixes and cleanups: - One-off fixes for various emulation flows (SGX, VMXON, NRIPS=0). - Reinstate IBPB on emulated VM-Exit that was incorrectly dropped a few years back when eliminating unnecessary barriers when switching between vmcs01 and vmcs02. - Clean up vmread_error_trampoline() to make it more obvious that params must be passed on the stack, even for x86-64. - Let userspace set all supported bits in MSR_IA32_FEAT_CTL irrespective of the current guest CPUID. - Fudge around a race with TSC refinement that results in KVM incorrectly thinking a guest needs TSC scaling when running on a CPU with a constant TSC, but no hardware-enumerated TSC frequency. - Advertise (on AMD) that the SMM_CTL MSR is not supported - Remove unnecessary exports Generic: - Support for responding to signals during page faults; introduces new FOLL_INTERRUPTIBLE flag that was reviewed by mm folks Selftests: - Fix an inverted check in the access tracking perf test, and restore support for asserting that there aren't too many idle pages when running on bare metal. - Fix build errors that occur in certain setups (unsure exactly what is unique about the problematic setup) due to glibc overriding static_assert() to a variant that requires a custom message. - Introduce actual atomics for clear/set_bit() in selftests - Add support for pinning vCPUs in dirty_log_perf_test. - Rename the so called "perf_util" framework to "memstress". - Add a lightweight psuedo RNG for guest use, and use it to randomize the access pattern and write vs. read percentage in the memstress tests. - Add a common ucall implementation; code dedup and pre-work for running SEV (and beyond) guests in selftests. - Provide a common constructor and arch hook, which will eventually be used by x86 to automatically select the right hypercall (AMD vs. Intel). - A bunch of added/enabled/fixed selftests for ARM64, covering memslots, breakpoints, stage-2 faults and access tracking. - x86-specific selftest changes: - Clean up x86's page table management. - Clean up and enhance the "smaller maxphyaddr" test, and add a related test to cover generic emulation failure. - Clean up the nEPT support checks. - Add X86_PROPERTY_* framework to retrieve multi-bit CPUID values. - Fix an ordering issue in the AMX test introduced by recent conversions to use kvm_cpu_has(), and harden the code to guard against similar bugs in the future. Anything that tiggers caching of KVM's supported CPUID, kvm_cpu_has() in this case, effectively hides opt-in XSAVE features if the caching occurs before the test opts in via prctl(). Documentation: - Remove deleted ioctls from documentation - Clean up the docs for the x86 MSR filter. - Various fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (361 commits) KVM: x86: Add proper ReST tables for userspace MSR exits/flags KVM: selftests: Allocate ucall pool from MEM_REGION_DATA KVM: arm64: selftests: Align VA space allocator with TTBR0 KVM: arm64: Fix benign bug with incorrect use of VA_BITS KVM: arm64: PMU: Fix period computation for 64bit counters with 32bit overflow KVM: x86: Advertise that the SMM_CTL MSR is not supported KVM: x86: remove unnecessary exports KVM: selftests: Fix spelling mistake "probabalistic" -> "probabilistic" tools: KVM: selftests: Convert clear/set_bit() to actual atomics tools: Drop "atomic_" prefix from atomic test_and_set_bit() tools: Drop conflicting non-atomic test_and_{clear,set}_bit() helpers KVM: selftests: Use non-atomic clear/set bit helpers in KVM tests perf tools: Use dedicated non-atomic clear/set bit helpers tools: Take @bit as an "unsigned long" in {clear,set}_bit() helpers KVM: arm64: selftests: Enable single-step without a "full" ucall() KVM: x86: fix APICv/x2AVIC disabled when vm reboot by itself KVM: Remove stale comment about KVM_REQ_UNHALT KVM: Add missing arch for KVM_CREATE_DEVICE and KVM_{SET,GET}_DEVICE_ATTR KVM: Reference to kvm_userspace_memory_region in doc and comments KVM: Delete all references to removed KVM_SET_MEMORY_ALIAS ioctl ...
2022-12-06s390/sclp: keep sclp_early_sccbHeiko Carstens1-3/+0
Keep sclp_early_sccb so it can also be used after initdata has been freed. This is a prerequisite to allow printing a message from the machine check handler. Reviewed-by: Peter Oberparleiter <[email protected]> Reviewed-by: Alexander Gordeev <[email protected]> Signed-off-by: Heiko Carstens <[email protected]> Signed-off-by: Alexander Gordeev <[email protected]>
2022-11-23s390/mm: provide minimal setup_per_cpu_areas() implementationHeiko Carstens1-0/+36
s390 allows to enable CONFIG_NUMA, mainly to enable a couple of system calls which are only present if NUMA is enabled. The NUMA specific system calls are required by a couple of applications, which wouldn't work if the system calls wouldn't be present. The NUMA implementation itself maps all CPUs and memory to node 0. A special case is the generic percpu setup code, which doesn't expect an s390 like implementation and therefore emits a message/warning: "percpu: cpu 0 has no node -1 or node-local memory". In order to get rid of this message, and also to provide sane CPU to node and CPU distance mappings implement a minimal setup_per_cpu_areas() function, which is very close to the generic variant. Signed-off-by: Heiko Carstens <[email protected]> Signed-off-by: Alexander Gordeev <[email protected]>
2022-11-07s390/mm: fix virtual-physical address confusion for swiotlbNico Boehr1-6/+6
swiotlb passes virtual addresses to set_memory_encrypted() and set_memory_decrypted(), but uv_remove_shared() and uv_set_shared() expect physical addresses. This currently works, because virtual and physical addresses are the same. Add virt_to_phys() to resolve the virtual-physical confusion. Reported-by: Marc Hartmayer <[email protected]> Signed-off-by: Nico Boehr <[email protected]> Reviewed-by: Claudio Imbrenda <[email protected]> Reviewed-by: Christian Borntraeger <[email protected]> Link: https://lore.kernel.org/r/[email protected] Message-Id: <[email protected]> Signed-off-by: Janosch Frank <[email protected]>
2022-09-14s390/smp: rework absolute lowcore accessAlexander Gordeev1-1/+1
Temporary unsetting of the prefix page in memcpy_absolute() routine poses a risk of executing code path with unexpectedly disabled prefix page. This rework avoids the prefix page uninstalling and disabling of normal and machine check interrupts when accessing the absolute zero memory. Although memcpy_absolute() routine can access the whole memory, it is only used to update the absolute zero lowcore. This rework therefore introduces a new mechanism for the absolute zero lowcore access and scraps memcpy_absolute() routine for good. Instead, an area is reserved in the virtual memory that is used for the absolute lowcore access only. That area holds an array of 8KB virtual mappings - one per CPU. Whenever a CPU is brought online, the corresponding item is mapped to the real address of the previously installed prefix page. The absolute zero lowcore access works like this: a CPU calls the new primitive get_abs_lowcore() to obtain its 8KB mapping as a pointer to the struct lowcore. Virtual address references to that pointer get translated to the real addresses of the prefix page, which in turn gets swapped with the absolute zero memory addresses due to prefixing. Once the pointer is not needed it must be released with put_abs_lowcore() primitive: struct lowcore *abs_lc; unsigned long flags; abs_lc = get_abs_lowcore(&flags); abs_lc->... = ...; put_abs_lowcore(abs_lc, flags); To ensure the described mechanism works large segment- and region- table entries must be avoided for the 8KB mappings. Failure to do so results in usage of Region-Frame Absolute Address (RFAA) or Segment-Frame Absolute Address (SFAA) large page fields. In that case absolute addresses would be used to address the prefix page instead of the real ones and the prefixing would get bypassed. Reviewed-by: Heiko Carstens <[email protected]> Signed-off-by: Alexander Gordeev <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
2022-08-01virtio: replace restricted mem access flag with callbackJuergen Gross1-2/+2
Instead of having a global flag to require restricted memory access for all virtio devices, introduce a callback which can select that requirement on a per-device basis. For convenience add a common function returning always true, which can be used for use cases like SEV. Per default use a callback always returning false. As the callback needs to be set in early init code already, add a virtio anchor which is builtin in case virtio is enabled. Signed-off-by: Juergen Gross <[email protected]> Tested-by: Oleksandr Tyshchenko <[email protected]> # Arm64 guest using Xen Reviewed-by: Stefano Stabellini <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Juergen Gross <[email protected]>
2022-06-06virtio: replace arch_has_restricted_virtio_memory_access()Juergen Gross1-10/+3
Instead of using arch_has_restricted_virtio_memory_access() together with CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, replace those with platform_has() and a new platform feature PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS. Signed-off-by: Juergen Gross <[email protected]> Reviewed-by: Oleksandr Tyshchenko <[email protected]> Tested-by: Oleksandr Tyshchenko <[email protected]> # Arm64 only Reviewed-by: Christoph Hellwig <[email protected]> Acked-by: Borislav Petkov <[email protected]>
2022-04-18swiotlb: make the swiotlb_init interface more usefulChristoph Hellwig1-2/+1
Pass a boolean flag to indicate if swiotlb needs to be enabled based on the addressing needs, and replace the verbose argument with a set of flags, including one to force enable bounce buffering. Note that this patch removes the possibility to force xen-swiotlb use with the swiotlb=force parameter on the command line on x86 (arm and arm64 never supported that), but this interface will be restored shortly. Signed-off-by: Christoph Hellwig <[email protected]> Reviewed-by: Konrad Rzeszutek Wilk <[email protected]> Tested-by: Boris Ostrovsky <[email protected]>
2021-12-16s390/sclp: release SCLP early buffer after kernel initializationAlexander Egorenkov1-0/+3
The SCLP early buffer is used only during kernel initialization and can be freed afterwards. The only way to ensure that it is not released while being in use, is to release it in free_initmem(). Acked-by: Heiko Carstens <[email protected]> Reviewed-by: Alexander Gordeev <[email protected]> Signed-off-by: Alexander Egorenkov <[email protected]> [[email protected]: added debug output] Signed-off-by: Alexander Gordeev <[email protected]> Signed-off-by: Heiko Carstens <[email protected]>
2021-11-06s390: use generic version of arch_is_kernel_initmem_freed()Christophe Leroy1-3/+0
The generic version of arch_is_kernel_initmem_freed() now does the same as s390 version. Remove the s390 version. Link: https://lkml.kernel.org/r/b6feb5dfe611a322de482762fc2df3a9eece70c7.1633001016.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <[email protected]> Acked-by: Heiko Carstens <[email protected]> Cc: Gerald Schaefer <[email protected]> Cc: Kefeng Wang <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-09-08Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-2/+1
Merge more updates from Andrew Morton: "147 patches, based on 7d2a07b769330c34b4deabeed939325c77a7ec2f. Subsystems affected by this patch series: mm (memory-hotplug, rmap, ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan), alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib, checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig, selftests, ipc, and scripts" * emailed patches from Andrew Morton <[email protected]>: (94 commits) scripts: check_extable: fix typo in user error message mm/workingset: correct kernel-doc notations ipc: replace costly bailout check in sysvipc_find_ipc() selftests/memfd: remove unused variable Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH configs: remove the obsolete CONFIG_INPUT_POLLDEV prctl: allow to setup brk for et_dyn executables pid: cleanup the stale comment mentioning pidmap_init(). kernel/fork.c: unexport get_{mm,task}_exe_file coredump: fix memleak in dump_vma_snapshot() fs/coredump.c: log if a core dump is aborted due to changed file permissions nilfs2: use refcount_dec_and_lock() to fix potential UAF nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group nilfs2: fix NULL pointer in nilfs_##name##_attr_release nilfs2: fix memory leak in nilfs_sysfs_create_device_group trap: cleanup trap_init() init: move usermodehelper_enable() to populate_rootfs() ...
2021-09-08mm/memory_hotplug: remove nid parameter from arch_remove_memory()David Hildenbrand1-2/+1
The parameter is unused, let's remove it. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Acked-by: Catalin Marinas <[email protected]> Acked-by: Michael Ellerman <[email protected]> [powerpc] Acked-by: Heiko Carstens <[email protected]> [s390] Reviewed-by: Pankaj Gupta <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Rich Felker <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Pavel Tatashin <[email protected]> Cc: Baoquan He <[email protected]> Cc: Laurent Dufour <[email protected]> Cc: Sergei Trofimovich <[email protected]> Cc: Kefeng Wang <[email protected]> Cc: Michel Lespinasse <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: "Aneesh Kumar K.V" <[email protected]> Cc: Thiago Jung Bauermann <[email protected]> Cc: Joe Perches <[email protected]> Cc: Pierre Morel <[email protected]> Cc: Jia He <[email protected]> Cc: Anton Blanchard <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Jiang <[email protected]> Cc: Jason Wang <[email protected]> Cc: Len Brown <[email protected]> Cc: "Michael S. Tsirkin" <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Nathan Lynch <[email protected]> Cc: Pankaj Gupta <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Scott Cheloha <[email protected]> Cc: Vishal Verma <[email protected]> Cc: Vitaly Kuznetsov <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Wei Yang <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-09-03Merge branch 'stable/for-linus-5.15' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb Pull swiotlb updates from Konrad Rzeszutek Wilk: "A new feature called restricted DMA pools. It allows SWIOTLB to utilize per-device (or per-platform) allocated memory pools instead of using the global one. The first big user of this is ARM Confidential Computing where the memory for DMA operations can be set per platform" * 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: (23 commits) swiotlb: use depends on for DMA_RESTRICTED_POOL of: restricted dma: Don't fail device probe on rmem init failure of: Move of_dma_set_restricted_buffer() into device.c powerpc/svm: Don't issue ultracalls if !mem_encrypt_active() s390/pv: fix the forcing of the swiotlb swiotlb: Free tbl memory in swiotlb_exit() swiotlb: Emit diagnostic in swiotlb_exit() swiotlb: Convert io_default_tlb_mem to static allocation of: Return success from of_dma_set_restricted_buffer() when !OF_ADDRESS swiotlb: add overflow checks to swiotlb_bounce swiotlb: fix implicit debugfs declarations of: Add plumbing for restricted DMA pool dt-bindings: of: Add restricted DMA pool swiotlb: Add restricted DMA pool initialization swiotlb: Add restricted DMA alloc/free support swiotlb: Refactor swiotlb_tbl_unmap_single swiotlb: Move alloc_size to swiotlb_find_slots swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing swiotlb: Update is_swiotlb_active to add a struct device argument swiotlb: Update is_swiotlb_buffer to add a struct device argument ...
2021-07-30s390: add support for KFENCESven Schnelle1-1/+2
Signed-off-by: Sven Schnelle <[email protected]> [[email protected]: simplify/rework code] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Heiko Carstens <[email protected]>
2021-07-23s390/pv: fix the forcing of the swiotlbHalil Pasic1-1/+1
Since commit 903cd0f315fe ("swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing") if code sets swiotlb_force it needs to do so before the swiotlb is initialised. Otherwise io_tlb_default_mem->force_bounce will not get set to true, and devices that use (the default) swiotlb will not bounce despite switolb_force having the value of SWIOTLB_FORCE. Let us restore swiotlb functionality for PV by fulfilling this new requirement. This change addresses what turned out to be a fragility in commit 64e1f0c531d1 ("s390/mm: force swiotlb for protected virtualization"), which ain't exactly broken in its original context, but could give us some more headache if people backport the broken change and forget this fix. Signed-off-by: Halil Pasic <[email protected]> Tested-by: Christian Borntraeger <[email protected]> Reviewed-by: Christian Borntraeger <[email protected]> Fixes: 903cd0f315fe ("swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing") Fixes: 64e1f0c531d1 ("s390/mm: force swiotlb for protected virtualization") Cc: [email protected] #5.3+ Signed-off-by: Konrad Rzeszutek Wilk <[email protected]>
2021-04-30mm: move mem_init_print_info() into mm_init()Kefeng Wang1-2/+0
mem_init_print_info() is called in mem_init() on each architecture, and pass NULL argument, so using void argument and move it into mm_init(). Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Kefeng Wang <[email protected]> Acked-by: Dave Hansen <[email protected]> [x86] Reviewed-by: Christophe Leroy <[email protected]> [powerpc] Acked-by: David Hildenbrand <[email protected]> Tested-by: Anatoly Pugachev <[email protected]> [sparc64] Acked-by: Russell King <[email protected]> [arm] Acked-by: Mike Rapoport <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Richard Henderson <[email protected]> Cc: Guo Ren <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Huacai Chen <[email protected]> Cc: Jonas Bonn <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: "Peter Zijlstra" <[email protected]> Cc: Ingo Molnar <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-02-26s390/mm: define arch_get_mappable_range()Anshuman Khandual1-0/+1
This overrides arch_get_mappabble_range() on s390 platform which will be used with recently added generic framework. It modifies the existing range check in vmem_add_mapping() using arch_get_mappable_range(). It also adds a VM_BUG_ON() check that would ensure that mhp_range_allowed() has already been called on the hotplug path. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Anshuman Khandual <[email protected]> Acked-by: Heiko Carstens <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Jason Wang <[email protected]> Cc: Jonathan Cameron <[email protected]> Cc: Mark Rutland <[email protected]> Cc: "Michael S. Tsirkin" <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Pankaj Gupta <[email protected]> Cc: Pankaj Gupta <[email protected]> Cc: teawater <[email protected]> Cc: Wei Yang <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2020-11-23s390/mm: use invalid asce instead of kernel asceHeiko Carstens1-2/+8
Create a region 3 page table which contains only invalid entries, and use that via "s390_invalid_asce" instead of the kernel ASCE whenever there is either - no user address space available, e.g. during early startup - as an intermediate ASCE when address spaces are switched This makes sure that user space accesses in such situations are guaranteed to fail. Reviewed-by: Sven Schnelle <[email protected]> Reviewed-by: Alexander Gordeev <[email protected]> Signed-off-by: Heiko Carstens <[email protected]>
2020-11-09s390/kasan: remove obvious parameter with the only possible valueVasily Gorbik1-1/+1
Kasan early code is only working on init_mm, remove unneeded pgd parameter from kasan_copy_shadow and rename it to kasan_copy_shadow_mapping. Reviewed-by: Alexander Egorenkov <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]> Signed-off-by: Heiko Carstens <[email protected]>
2020-10-25treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches1-1/+1
Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/[email protected]/2-convert_section.pl Signed-off-by: Joe Perches <[email protected]> Reviewed-by: Nick Desaulniers <[email protected]> Reviewed-by: Miguel Ojeda <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2020-10-23Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-0/+11
Pull virtio updates from Michael Tsirkin: "vhost, vdpa, and virtio cleanups and fixes A very quiet cycle, no new features" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: MAINTAINERS: add URL for virtio-mem vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call vringh: fix __vringh_iov() when riov and wiov are different vdpa/mlx5: Setup driver only if VIRTIO_CONFIG_S_DRIVER_OK s390: virtio: PV needs VIRTIO I/O device protection virtio: let arch advertise guest's memory access restrictions vhost_vdpa: Fix duplicate included kernel.h vhost: reduce stack usage in log_used virtio-mem: Constify mem_id_table virtio_input: Constify id_table virtio-balloon: Constify id_table vdpa/mlx5: Fix failure to bring link up vdpa/mlx5: Make use of a specific 16 bit endianness API
2020-10-21s390: virtio: PV needs VIRTIO I/O device protectionPierre Morel1-0/+11
If protected virtualization is active on s390, VIRTIO has only retricted access to the guest memory. Define CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS and export arch_has_restricted_virtio_memory_access to advertize VIRTIO if that's the case. Signed-off-by: Pierre Morel <[email protected]> Reviewed-by: Cornelia Huck <[email protected]> Reviewed-by: Halil Pasic <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Michael S. Tsirkin <[email protected]> Acked-by: Christian Borntraeger <[email protected]>
2020-09-14s390: add ARCH_HAS_DEBUG_WX supportHeiko Carstens1-0/+2
Checks the whole kernel address space for W+X mappings. Note that currently the first lowcore page unfortunately has to be mapped W+X. Therefore this not reported as an insecure mapping. For the very same reason the wording is also different to other architectures if the test passes: On s390 it is "no unexpected W+X pages found" instead of "no W+X pages found". Tested-by: Vasily Gorbik <[email protected]> Signed-off-by: Heiko Carstens <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
2020-08-07mm/sparse: cleanup the code surrounding memory_present()Mike Rapoport1-1/+0
After removal of CONFIG_HAVE_MEMBLOCK_NODE_MAP we have two equivalent functions that call memory_present() for each region in memblock.memory: sparse_memory_present_with_active_regions() and membocks_present(). Moreover, all architectures have a call to either of these functions preceding the call to sparse_init() and in the most cases they are called one after the other. Mark the regions from memblock.memory as present during sparce_init() by making sparse_init() call memblocks_present(), make memblocks_present() and memory_present() functions static and remove redundant sparse_memory_present_with_active_regions() function. Also remove no longer required HAVE_MEMORY_PRESENT configuration option. Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-09mm: don't include asm/pgtable.h if linux/mm.h is already includedMike Rapoport1-1/+0
Patch series "mm: consolidate definitions of page table accessors", v2. The low level page table accessors (pXY_index(), pXY_offset()) are duplicated across all architectures and sometimes more than once. For instance, we have 31 definition of pgd_offset() for 25 supported architectures. Most of these definitions are actually identical and typically it boils down to, e.g. static inline unsigned long pmd_index(unsigned long address) { return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); } static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) { return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); } These definitions can be shared among 90% of the arches provided XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined. For architectures that really need a custom version there is always possibility to override the generic version with the usual ifdefs magic. These patches introduce include/linux/pgtable.h that replaces include/asm-generic/pgtable.h and add the definitions of the page table accessors to the new header. This patch (of 12): The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the functions involving page table manipulations, e.g. pte_alloc() and pmd_alloc(). So, there is no point to explicitly include <asm/pgtable.h> in the files that include <linux/mm.h>. The include statements in such cases are remove with a simple loop: for f in $(git grep -l "include <linux/mm.h>") ; do sed -i -e '/include <asm\/pgtable.h>/ d' $f done Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Cain <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Chris Zankel <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Ungerer <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Guo Ren <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Helge Deller <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Mark Salter <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Matt Turner <[email protected]> Cc: Max Filippov <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Simek <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Nick Hu <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Rich Felker <[email protected]> Cc: Russell King <[email protected]> Cc: Stafford Horne <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Vincent Chen <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Will Deacon <[email protected]> Cc: Yoshinori Sato <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-06-03mm: use free_area_init() instead of free_area_init_nodes()Mike Rapoport1-1/+1
free_area_init() has effectively became a wrapper for free_area_init_nodes() and there is no point of keeping it. Still free_area_init() name is shorter and more general as it does not imply necessity to initialize multiple nodes. Rename free_area_init_nodes() to free_area_init(), update the callers and drop old version of free_area_init(). Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Tested-by: Hoan Tran <[email protected]> [arm64] Reviewed-by: Baoquan He <[email protected]> Acked-by: Catalin Marinas <[email protected]> Cc: Brian Cain <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Ungerer <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Guo Ren <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Helge Deller <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Mark Salter <[email protected]> Cc: Matt Turner <[email protected]> Cc: Max Filippov <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Michal Simek <[email protected]> Cc: Nick Hu <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Rich Felker <[email protected]> Cc: Russell King <[email protected]> Cc: Stafford Horne <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Tony Luck <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Yoshinori Sato <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-10mm/memory_hotplug: add pgprot_t to mhp_paramsLogan Gunthorpe1-0/+3
devm_memremap_pages() is currently used by the PCI P2PDMA code to create struct page mappings for IO memory. At present, these mappings are created with PAGE_KERNEL which implies setting the PAT bits to be WB. However, on x86, an mtrr register will typically override this and force the cache type to be UC-. In the case firmware doesn't set this register it is effectively WB and will typically result in a machine check exception when it's accessed. Other arches are not currently likely to function correctly seeing they don't have any MTRR registers to fall back on. To solve this, provide a way to specify the pgprot value explicitly to arch_add_memory(). Of the arches that support MEMORY_HOTPLUG: x86_64, and arm64 need a simple change to pass the pgprot_t down to their respective functions which set up the page tables. For x86_32, set the page tables explicitly using _set_memory_prot() (seeing they are already mapped). For ia64, s390 and sh, reject anything but PAGE_KERNEL settings -- this should be fine, for now, seeing these architectures don't support ZONE_DEVICE. A check in __add_pages() is also added to ensure the pgprot parameter was set for all arches. Signed-off-by: Logan Gunthorpe <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Acked-by: David Hildenbrand <[email protected]> Acked-by: Michal Hocko <[email protected]> Acked-by: Dan Williams <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Eric Badger <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Deacon <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-10mm/memory_hotplug: rename mhp_restrictions to mhp_paramsLogan Gunthorpe1-3/+3
The mhp_restrictions struct really doesn't specify anything resembling a restriction anymore so rename it to be mhp_params as it is a list of extended parameters. Signed-off-by: Logan Gunthorpe <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Reviewed-by: Dan Williams <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Eric Badger <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Deacon <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-01-04mm/memory_hotplug: shrink zones when offlining memoryDavid Hildenbrand1-3/+1
We currently try to shrink a single zone when removing memory. We use the zone of the first page of the memory we are removing. If that memmap was never initialized (e.g., memory was never onlined), we will read garbage and can trigger kernel BUGs (due to a stale pointer): BUG: unable to handle page fault for address: 000000000000353d #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP PTI CPU: 1 PID: 7 Comm: kworker/u8:0 Not tainted 5.3.0-rc5-next-20190820+ #317 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.4 Workqueue: kacpi_hotplug acpi_hotplug_work_fn RIP: 0010:clear_zone_contiguous+0x5/0x10 Code: 48 89 c6 48 89 c3 e8 2a fe ff ff 48 85 c0 75 cf 5b 5d c3 c6 85 fd 05 00 00 01 5b 5d c3 0f 1f 840 RSP: 0018:ffffad2400043c98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000200000000 RCX: 0000000000000000 RDX: 0000000000200000 RSI: 0000000000140000 RDI: 0000000000002f40 RBP: 0000000140000000 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000140000 R13: 0000000000140000 R14: 0000000000002f40 R15: ffff9e3e7aff3680 FS: 0000000000000000(0000) GS:ffff9e3e7bb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000353d CR3: 0000000058610000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __remove_pages+0x4b/0x640 arch_remove_memory+0x63/0x8d try_remove_memory+0xdb/0x130 __remove_memory+0xa/0x11 acpi_memory_device_remove+0x70/0x100 acpi_bus_trim+0x55/0x90 acpi_device_hotplug+0x227/0x3a0 acpi_hotplug_work_fn+0x1a/0x30 process_one_work+0x221/0x550 worker_thread+0x50/0x3b0 kthread+0x105/0x140 ret_from_fork+0x3a/0x50 Modules linked in: CR2: 000000000000353d Instead, shrink the zones when offlining memory or when onlining failed. Introduce and use remove_pfn_range_from_zone(() for that. We now properly shrink the zones, even if we have DIMMs whereby - Some memory blocks fall into no zone (never onlined) - Some memory blocks fall into multiple zones (offlined+re-onlined) - Multiple memory blocks that fall into different zones Drop the zone parameter (with a potential dubious value) from __remove_pages() and __remove_section(). Link: http://lkml.kernel.org/r/[email protected] Fixes: f1dd2cd13c4b ("mm, memory_hotplug: do not associate hotadded memory to zones until online") [visible after d0dc12e86b319] Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Cc: Michal Hocko <[email protected]> Cc: "Matthew Wilcox (Oracle)" <[email protected]> Cc: "Aneesh Kumar K.V" <[email protected]> Cc: Pavel Tatashin <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Dan Williams <[email protected]> Cc: Logan Gunthorpe <[email protected]> Cc: <[email protected]> [5.0+] Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-11-01dma/direct: turn ARCH_ZONE_DMA_BITS into a variableNicolas Saenz Julienne1-0/+1
Some architectures, notably ARM, are interested in tweaking this depending on their runtime DMA addressing limitations. Acked-by: Christoph Hellwig <[email protected]> Signed-off-by: Nicolas Saenz Julienne <[email protected]> Signed-off-by: Catalin Marinas <[email protected]>
2019-08-09s390/mm: Remove sev_active() functionThiago Jung Bauermann1-6/+1
All references to sev_active() were moved to arch/x86 so we don't need to define it for s390 anymore. Signed-off-by: Thiago Jung Bauermann <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Reviewed-by: Halil Pasic <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2019-07-20Merge tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-1/+6
Pull dma-mapping fixes from Christoph Hellwig: "Fix various regressions: - force unencrypted dma-coherent buffers if encryption bit can't fit into the dma coherent mask (Tom Lendacky) - avoid limiting request size if swiotlb is not used (me) - fix swiotlb handling in dma_direct_sync_sg_for_cpu/device (Fugang Duan)" * tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping: dma-direct: correct the physical addr in dma_direct_sync_sg_for_cpu/device dma-direct: only limit the mapping size if swiotlb could be used dma-mapping: add a dma_addressing_limited helper dma-direct: Force unencrypted DMA under SME for certain DMA masks
2019-07-18mm/memory_hotplug: allow arch_remove_memory() without CONFIG_MEMORY_HOTREMOVEDavid Hildenbrand1-2/+0
We want to improve error handling while adding memory by allowing to use arch_remove_memory() and __remove_pages() even if CONFIG_MEMORY_HOTREMOVE is not set to e.g., implement something like: arch_add_memory() rc = do_something(); if (rc) { arch_remove_memory(); } We won't get rid of CONFIG_MEMORY_HOTREMOVE for now, as it will require quite some dependencies for memory offlining. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Pavel Tatashin <[email protected]> Cc: Tony Luck <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Rich Felker <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Michal Hocko <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Alex Deucher <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Mark Brown <[email protected]> Cc: Chris Wilson <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Rob Herring <[email protected]> Cc: Masahiro Yamada <[email protected]> Cc: "[email protected]" <[email protected]> Cc: Andrew Banman <[email protected]> Cc: Arun KS <[email protected]> Cc: Qian Cai <[email protected]> Cc: Mathieu Malaterre <[email protected]> Cc: Baoquan He <[email protected]> Cc: Logan Gunthorpe <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Chintan Pandya <[email protected]> Cc: Dan Williams <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jonathan Cameron <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Jun Yao <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Robin Murphy <[email protected]> Cc: Wei Yang <[email protected]> Cc: Will Deacon <[email protected]> Cc: Yu Zhao <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-07-18s390x/mm: implement arch_remove_memory()David Hildenbrand1-6/+7
Will come in handy when wanting to handle errors after arch_add_memory(). Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Alex Deucher <[email protected]> Cc: Andrew Banman <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Arun KS <[email protected]> Cc: Baoquan He <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Chintan Pandya <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Chris Wilson <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Hansen <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jonathan Cameron <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Jun Yao <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Logan Gunthorpe <[email protected]> Cc: Mark Brown <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Masahiro Yamada <[email protected]> Cc: Mathieu Malaterre <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: "[email protected]" <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Pavel Tatashin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Qian Cai <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Rich Felker <[email protected]> Cc: Rob Herring <[email protected]> Cc: Robin Murphy <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Wei Yang <[email protected]> Cc: Will Deacon <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Yu Zhao <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-07-18s390x/mm: fail when an altmap is used for arch_add_memory()David Hildenbrand1-0/+3
ZONE_DEVICE is not yet supported, fail if an altmap is passed, so we don't forget arch_add_memory()/arch_remove_memory() when unlocking support. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Suggested-by: Dan Williams <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Alex Deucher <[email protected]> Cc: Andrew Banman <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Arun KS <[email protected]> Cc: Baoquan He <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Chintan Pandya <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Chris Wilson <[email protected]> Cc: Dave Hansen <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jonathan Cameron <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Jun Yao <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Logan Gunthorpe <[email protected]> Cc: Mark Brown <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Masahiro Yamada <[email protected]> Cc: Mathieu Malaterre <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: "[email protected]" <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Pavel Tatashin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Qian Cai <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Rich Felker <[email protected]> Cc: Rob Herring <[email protected]> Cc: Robin Murphy <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Wei Yang <[email protected]> Cc: Will Deacon <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Yu Zhao <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-07-16dma-direct: Force unencrypted DMA under SME for certain DMA masksTom Lendacky1-1/+6
If a device doesn't support DMA to a physical address that includes the encryption bit (currently bit 47, so 48-bit DMA), then the DMA must occur to unencrypted memory. SWIOTLB is used to satisfy that requirement if an IOMMU is not active (enabled or configured in passthrough mode). However, commit fafadcd16595 ("swiotlb: don't dip into swiotlb pool for coherent allocations") modified the coherent allocation support in SWIOTLB to use the DMA direct coherent allocation support. When an IOMMU is not active, this resulted in dma_alloc_coherent() failing for devices that didn't support DMA addresses that included the encryption bit. Addressing this requires changes to the force_dma_unencrypted() function in kernel/dma/direct.c. Since the function is now non-trivial and SME/SEV specific, update the DMA direct support to add an arch override for the force_dma_unencrypted() function. The arch override is selected when CONFIG_AMD_MEM_ENCRYPT is set. The arch override function resides in the arch/x86/mm/mem_encrypt.c file and forces unencrypted DMA when either SEV is active or SME is active and the device does not support DMA to physical addresses that include the encryption bit. Fixes: fafadcd16595 ("swiotlb: don't dip into swiotlb pool for coherent allocations") Suggested-by: Christoph Hellwig <[email protected]> Signed-off-by: Tom Lendacky <[email protected]> Acked-by: Thomas Gleixner <[email protected]> [hch: moved the force_dma_unencrypted declaration to dma-mapping.h, fold the s390 fix from Halil Pasic] Signed-off-by: Christoph Hellwig <[email protected]>
2019-06-15s390/mm: force swiotlb for protected virtualizationHalil Pasic1-0/+47
On s390, protected virtualization guests have to use bounced I/O buffers. That requires some plumbing. Let us make sure, any device that uses DMA API with direct ops correctly is spared from the problems, that a hypervisor attempting I/O to a non-shared page would bring. Signed-off-by: Halil Pasic <[email protected]> Reviewed-by: Claudio Imbrenda <[email protected]> Reviewed-by: Michael Mueller <[email protected]> Tested-by: Michael Mueller <[email protected]> Signed-off-by: Heiko Carstens <[email protected]>
2019-05-14mm/memory_hotplug: make __remove_pages() and arch_remove_memory() never failDavid Hildenbrand1-2/+3
All callers of arch_remove_memory() ignore errors. And we should really try to remove any errors from the memory removal path. No more errors are reported from __remove_pages(). BUG() in s390x code in case arch_remove_memory() is triggered. We may implement that properly later. WARN in case powerpc code failed to remove the section mapping, which is better than ignoring the error completely right now. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Cc: Tony Luck <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Rich Felker <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Stefan Agner <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Pavel Tatashin <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Arun KS <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Masahiro Yamada <[email protected]> Cc: Rob Herring <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Wei Yang <[email protected]> Cc: Qian Cai <[email protected]> Cc: Mathieu Malaterre <[email protected]> Cc: Andrew Banman <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Mike Travis <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-05-14mm, memory_hotplug: provide a more generic restrictions for memory hotplugMichal Hocko1-3/+3
arch_add_memory, __add_pages take a want_memblock which controls whether the newly added memory should get the sysfs memblock user API (e.g. ZONE_DEVICE users do not want/need this interface). Some callers even want to control where do we allocate the memmap from by configuring altmap. Add a more generic hotplug context for arch_add_memory and __add_pages. struct mhp_restrictions contains flags which contains additional features to be enabled by the memory hotplug (MHP_MEMBLOCK_API currently) and altmap for alternative memmap allocator. This patch shouldn't introduce any functional change. [[email protected]: build fix] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Michal Hocko <[email protected]> Signed-off-by: Oscar Salvador <[email protected]> Cc: Dan Williams <[email protected]> Cc: David Hildenbrand <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-05-14initramfs: poison freed initrd memoryChristoph Hellwig1-8/+0
Various architectures including x86 poison the freed initrd memory. Do the same in the generic free_initrd_mem implementation and switch a few more architectures that are identical to the generic code over to it now. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Christoph Hellwig <[email protected]> Acked-by: Mike Rapoport <[email protected]> Cc: Catalin Marinas <[email protected]> [arm64] Cc: Geert Uytterhoeven <[email protected]> [m68k] Cc: Steven Price <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Russell King <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-04-29locking/lockdep: check for freed initmem in static_obj()Gerald Schaefer1-0/+3
The following warning occurred on s390: WARNING: CPU: 0 PID: 804 at kernel/locking/lockdep.c:1025 lockdep_register_key+0x30/0x150 This is because the check in static_obj() assumes that all memory within [_stext, _end] belongs to static objects, which at least for s390 isn't true. The init section is also part of this range, and freeing it allows the buddy allocator to allocate memory from it. We have virt == phys for the kernel on s390, so that such allocations would then have addresses within the range [_stext, _end]. To fix this, introduce arch_is_kernel_initmem_freed(), similar to arch_is_kernel_text/data(), and add it to the checks in static_obj(). This will always return 0 on architectures that do not define arch_is_kernel_initmem_freed. On s390, it will return 1 if initmem has been freed and the address is in the range [__init_begin, __init_end]. Signed-off-by: Gerald Schaefer <[email protected]> Reviewed-by: Heiko Carstens <[email protected]> Signed-off-by: Martin Schwidefsky <[email protected]>
2018-12-28mm, memory_hotplug: add nid parameter to arch_remove_memoryOscar Salvador1-1/+1
Patch series "Do not touch pages in hot-remove path", v2. This patchset aims for two things: 1) A better definition about offline and hot-remove stage 2) Solving bugs where we can access non-initialized pages during hot-remove operations [2] [3]. This is achieved by moving all page/zone handling to the offline stage, so we do not need to access pages when hot-removing memory. [1] https://patchwork.kernel.org/cover/10691415/ [2] https://patchwork.kernel.org/patch/10547445/ [3] https://www.spinics.net/lists/linux-mm/msg161316.html This patch (of 5): This is a preparation for the following-up patches. The idea of passing the nid is that it will allow us to get rid of the zone parameter afterwards. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Oscar Salvador <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Reviewed-by: Pavel Tatashin <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Dan Williams <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: Jonathan Cameron <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-12-28mm: convert totalram_pages and totalhigh_pages variables to atomicArun KS1-1/+1
totalram_pages and totalhigh_pages are made static inline function. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes better to remove the lock and convert variables to atomic, with preventing poteintial store-to-read tearing as a bonus. [[email protected]: coding style fixes] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arun KS <[email protected]> Suggested-by: Michal Hocko <[email protected]> Suggested-by: Vlastimil Babka <[email protected]> Reviewed-by: Konstantin Khlebnikov <[email protected]> Reviewed-by: Pavel Tatashin <[email protected]> Acked-by: Michal Hocko <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: David Hildenbrand <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-10-31mm: remove include/linux/bootmem.hMike Rapoport1-2/+1
Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include <linux/memblock.h> @@ @@ - #include <linux/bootmem.h> + #include <linux/memblock.h> [[email protected]: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/[email protected] [[email protected]: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/[email protected] [[email protected]: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Stephen Rothwell <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Chris Zankel <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Jonas Bonn <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Mark Salter <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Matt Turner <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Simek <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Paul Burton <[email protected]> Cc: Richard Kuo <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Rich Felker <[email protected]> Cc: Russell King <[email protected]> Cc: Serge Semin <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Yoshinori Sato <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-10-31memblock: rename free_all_bootmem to memblock_free_allMike Rapoport1-1/+1
The conversion is done using sed -i 's@free_all_bootmem@memblock_free_all@' \ $(git grep -l free_all_bootmem) Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Chris Zankel <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "James E.J. Bottomley" <[email protected]> Cc: Jonas Bonn <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Mark Salter <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Matt Turner <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Michal Simek <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Paul Burton <[email protected]> Cc: Richard Kuo <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Rich Felker <[email protected]> Cc: Russell King <[email protected]> Cc: Serge Semin <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Yoshinori Sato <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-10-09s390/kasan: free early identity mapping structuresVasily Gorbik1-0/+1
Kasan initialization code is changed to populate persistent shadow first, save allocator position into pgalloc_freeable and proceed with early identity mapping creation. This way early identity mapping paging structures could be freed at once after switching to swapper_pg_dir when early identity mapping is not needed anymore. Reviewed-by: Martin Schwidefsky <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]> Signed-off-by: Martin Schwidefsky <[email protected]>
2018-10-09s390/kasan: add initialization code and enable itVasily Gorbik1-1/+3
Kasan needs 1/8 of kernel virtual address space to be reserved as the shadow area. And eventually it requires the shadow memory offset to be known at compile time (passed to the compiler when full instrumentation is enabled). Any value picked as the shadow area offset for 3-level paging would eat up identity mapping on 4-level paging (with 1PB shadow area size). So, the kernel sticks to 3-level paging when kasan is enabled. 3TB border is picked as the shadow offset. The memory layout is adjusted so, that physical memory border does not exceed KASAN_SHADOW_START and vmemmap does not go below KASAN_SHADOW_END. Due to the fact that on s390 paging is set up very late and to cover more code with kasan instrumentation, temporary identity mapping and final shadow memory are set up early. The shadow memory mapping is later carried over to init_mm.pgd during paging_init. For the needs of paging structures allocation and shadow memory population a primitive allocator is used, which simply chops off memory blocks from the end of the physical memory. Kasan currenty doesn't track vmemmap and vmalloc areas. Current memory layout (for 3-level paging, 2GB physical memory). ---[ Identity Mapping ]--- 0x0000000000000000-0x0000000000100000 ---[ Kernel Image Start ]--- 0x0000000000100000-0x0000000002b00000 ---[ Kernel Image End ]--- 0x0000000002b00000-0x0000000080000000 2G <- physical memory border 0x0000000080000000-0x0000030000000000 3070G PUD I ---[ Kasan Shadow Start ]--- 0x0000030000000000-0x0000030010000000 256M PMD RW X <- shadow for 2G memory 0x0000030010000000-0x0000037ff0000000 523776M PTE RO NX <- kasan zero ro page 0x0000037ff0000000-0x0000038000000000 256M PMD RW X <- shadow for 2G modules ---[ Kasan Shadow End ]--- 0x0000038000000000-0x000003d100000000 324G PUD I ---[ vmemmap Area ]--- 0x000003d100000000-0x000003e080000000 ---[ vmalloc Area ]--- 0x000003e080000000-0x000003ff80000000 ---[ Modules Area ]--- 0x000003ff80000000-0x0000040000000000 2G Acked-by: Martin Schwidefsky <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]> Signed-off-by: Martin Schwidefsky <[email protected]>
2018-01-08mm: pass the vmem_altmap to arch_remove_memory and __remove_pagesChristoph Hellwig1-1/+1
We can just pass this on instead of having to do a radix tree lookup without proper locking 2 levels into the callchain. Signed-off-by: Christoph Hellwig <[email protected]> Signed-off-by: Dan Williams <[email protected]>
2018-01-08mm: pass the vmem_altmap to arch_add_memory and __add_pagesChristoph Hellwig1-2/+3
We can just pass this on instead of having to do a radix tree lookup without proper locking 2 levels into the callchain. Signed-off-by: Christoph Hellwig <[email protected]> Signed-off-by: Dan Williams <[email protected]>
2017-11-14s390: remove all code using the access register modeMartin Schwidefsky1-0/+1
The vdso code for the getcpu() and the clock_gettime() call use the access register mode to access the per-CPU vdso data page with the current code. An alternative to the complicated AR mode is to use the secondary space mode. This makes the vdso faster and quite a bit simpler. The downside is that the uaccess code has to be changed quite a bit. Which instructions are used depends on the machine and what kind of uaccess operation is requested. The instruction dictates which ASCE value needs to be loaded into %cr1 and %cr7. The different cases: * User copy with MVCOS for z10 and newer machines The MVCOS instruction can copy between the primary space (aka user) and the home space (aka kernel) directly. For set_fs(KERNEL_DS) the kernel ASCE is loaded into %cr1. For set_fs(USER_DS) the user space is already loaded in %cr1. * User copy with MVCP/MVCS for older machines To be able to execute the MVCP/MVCS instructions the kernel needs to switch to primary mode. The control register %cr1 has to be set to the kernel ASCE and %cr7 to either the kernel ASCE or the user ASCE dependent on set_fs(KERNEL_DS) vs set_fs(USER_DS). * Data access in the user address space for strnlen / futex To use "normal" instruction with data from the user address space the secondary space mode is used. The kernel needs to switch to primary mode, %cr1 has to contain the kernel ASCE and %cr7 either the user ASCE or the kernel ASCE, dependent on set_fs. To load a new value into %cr1 or %cr7 is an expensive operation, the kernel tries to be lazy about it. E.g. for multiple user copies in a row with MVCP/MVCS the replacement of the vdso ASCE in %cr7 with the user ASCE is done only once. On return to user space a CPU bit is checked that loads the vdso ASCE again. To enable and disable the data access via the secondary space two new functions are added, enable_sacf_uaccess and disable_sacf_uaccess. The fact that a context is in secondary space uaccess mode is stored in the mm_segment_t value for the task. The code of an interrupt may use set_fs as long as it returns to the previous state it got with get_fs with another call to set_fs. The code in finish_arch_post_lock_switch simply has to do a set_fs with the current mm_segment_t value for the task. For CPUs with MVCOS: CPU running in | %cr1 ASCE | %cr7 ASCE | --------------------------------------|-----------|-----------| user space | user | vdso | kernel, USER_DS, normal-mode | user | vdso | kernel, USER_DS, normal-mode, lazy | user | user | kernel, USER_DS, sacf-mode | kernel | user | kernel, KERNEL_DS, normal-mode | kernel | vdso | kernel, KERNEL_DS, normal-mode, lazy | kernel | kernel | kernel, KERNEL_DS, sacf-mode | kernel | kernel | For CPUs without MVCOS: CPU running in | %cr1 ASCE | %cr7 ASCE | --------------------------------------|-----------|-----------| user space | user | vdso | kernel, USER_DS, normal-mode | user | vdso | kernel, USER_DS, normal-mode lazy | kernel | user | kernel, USER_DS, sacf-mode | kernel | user | kernel, KERNEL_DS, normal-mode | kernel | vdso | kernel, KERNEL_DS, normal-mode, lazy | kernel | kernel | kernel, KERNEL_DS, sacf-mode | kernel | kernel | The lines with "lazy" refer to the state after a copy via the secondary space with a delayed reload of %cr1 and %cr7. There are three hardware address spaces that can cause a DAT exception, primary, secondary and home space. The exception can be related to four different fault types: user space fault, vdso fault, kernel fault, and the gmap faults. Dependent on the set_fs state and normal vs. sacf mode there are a number of fault combinations: 1) user address space fault via the primary ASCE 2) gmap address space fault via the primary ASCE 3) kernel address space fault via the primary ASCE for machines with MVCOS and set_fs(KERNEL_DS) 4) vdso address space faults via the secondary ASCE with an invalid address while running in secondary space in problem state 5) user address space fault via the secondary ASCE for user-copy based on the secondary space mode, e.g. futex_ops or strnlen_user 6) kernel address space fault via the secondary ASCE for user-copy with secondary space mode with set_fs(KERNEL_DS) 7) kernel address space fault via the primary ASCE for user-copy with secondary space mode with set_fs(USER_DS) on machines without MVCOS. 8) kernel address space fault via the home space ASCE Replace user_space_fault() with a new function get_fault_type() that can distinguish all four different fault types. With these changes the futex atomic ops from the kernel and the strnlen_user will get a little bit slower, as well as the old style uaccess with MVCP/MVCS. All user accesses based on MVCOS will be as fast as before. On the positive side, the user space vdso code is a lot faster and Linux ceases to use the complicated AR mode. Reviewed-by: Heiko Carstens <[email protected]> Signed-off-by: Martin Schwidefsky <[email protected]> Signed-off-by: Heiko Carstens <[email protected]>