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2017-05-09Merge branch 'mlx4-misc-fixes'David S. Miller
Tariq Toukan says: ==================== mlx4 misc fixes This patchset contains misc bug fixes from the team to the mlx4 Core and Eth drivers. Series generated against net commit: 32f1bc0f3d26 Revert "ipv4: restore rt->fi for reference counting" ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-09net/mlx4_core: Reduce harmless SRIOV error message to debug levelJack Morgenstein
Under SRIOV resource management, extra counters are allocated to VFs from a free pool. If that pool is empty, the ALLOC_RES command for a counter resource fails -- and this generates a misleading error message in the message log. Under SRIOV, each VF is allocated (i.e., guaranteed) 2 counters -- one counter per port. For ETH ports, the RoCE driver requests an additional counter (above the guaranteed counters). If that request fails, the VF RoCE driver simply uses the default (i.e., guaranteed) counter for that port. Thus, failing to allocate an additional counter does not constitute a problem, and the error message on the PF when this occurs should be reduced to debug level. Finally, to identify the situation that the reason for the failure is that no resources are available to grant to the VF, we modified the error returned by mlx4_grant_resource to -EDQUOT (Quota exceeded), which more accurately describes the error. Fixes: c3abb51bdb0e ("IB/mlx4: Add RoCE/IB dedicated counters") Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-09net/mlx4_en: Avoid adding steering rules with invalid ringTalat Batheesh
Inserting steering rules with illegal ring is an invalid operation, block it. Fixes: 820672812f82 ('net/mlx4_en: Manage flow steering rules with ethtool') Signed-off-by: Talat Batheesh <talatb@mellanox.com> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-09net/mlx4_en: Change the error print to debug printKamal Heib
The error print within mlx4_en_calc_rx_buf() should be a debug print. Fixes: 51151a16a60f ('mlx4: allow order-0 memory allocations in RX path') Signed-off-by: Kamal Heib <kamalh@mellanox.com> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-09s390/virtio: change maintainershipChristian Borntraeger
Halil is doing a lot more work in the virtio area on s390 than I do. Let's reflect the reality in the maintainers file. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Halil Pasic <pasic@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09tools/virtio: fix spelling mistake: "wakeus" -> "wakeups"Colin Ian King
trivial fix to spelling mistake in an error message. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2017-05-09virtio_net: tidy a couple debug statementsDan Carpenter
We are printing a decimal value for truesize so we shouldn't use an "0x" prefix. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09ptr_ring: support testing different batching sizesMichael S. Tsirkin
Use the param flag for that. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09ringtest: support test specific parametersMichael S. Tsirkin
Add a new flag for passing test-specific parameters. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09ptr_ring: batch ring zeroingMichael S. Tsirkin
A known weakness in ptr_ring design is that it does not handle well the situation when ring is almost full: as entries are consumed they are immediately used again by the producer, so consumer and producer are writing to a shared cache line. To fix this, add batching to consume calls: as entries are consumed do not write NULL into the ring until we get a multiple (in current implementation 2x) of cache lines away from the producer. At that point, write them all out. We do the write out in the reverse order to keep producer from sharing cache with consumer for as long as possible. Writeout also triggers when ring wraps around - there's no special reason to do this but it helps keep the code a bit simpler. What should we do if getting away from producer by 2 cache lines would mean we are keeping the ring moe than half empty? Maybe we should reduce the batching in this case, current patch simply reduces the batching. Notes: - it is no longer true that a call to consume guarantees that the following call to produce will succeed. No users seem to assume that. - batching can also in theory reduce the signalling rate: users that would previously send interrups to the producer to wake it up after consuming each entry would now only need to do this once in a batch. Doing this would be easy by returning a flag to the caller. No users seem to do signalling on consume yet so this was not implemented yet. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2017-05-09virtio: virtio_driver docCornelia Huck
Add comments for the virtio_driver members that were not documented. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09virtio_net: don't reset twice on XDP on/offMichael S. Tsirkin
We already do a reset once in remove_vq_common - there appears to be no point in doing another one when we add/remove XDP. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09virtio_net: fix support for small ringsMichael S. Tsirkin
When ring size is small (<32 entries) making buffers smaller means a full ring might not be able to hold enough buffers to fit a single large packet. Make sure a ring full of buffers is large enough to allow at least one packet of max size. Fixes: 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09virtio_net: reduce alignment for buffersMichael S. Tsirkin
We don't need to align length to any particular value anymore. Aligning to L1 cache size probably sill makes sense to reduce false sharing. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09virtio_net: rework mergeable buffer handlingMichael S. Tsirkin
Use the new _ctx virtio API to maintain true length for each buffer. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09virtio_net: allow specifying context for rxMichael S. Tsirkin
With mergeable buffers we never use s/g for rx, so allow specifying context in that case. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-09powerpc/64s: Support new device tree binding for discovering CPU featuresNicholas Piggin
The ibm,powerpc-cpu-features device tree binding describes CPU features with ASCII names and extensible compatibility, privilege, and enablement metadata that allows improved flexibility and compatibility with new hardware. The interface is described in detail in ibm,powerpc-cpu-features.txt in this patch. Currently this code is not enabled by default, and there are no released firmwares that provide the binding. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-09drivers: net: wimax: i2400m: i2400m-usb: Use time_after for time comparisonKarim Eshapa
Use time_after() for time comparison with the new fix. Signed-off-by: Karim Eshapa <karim.eshapa@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-09DECnet: Use container_of() for embedded structKees Cook
Instead of a direct cross-type cast, use conatiner_of() to locate the embedded structure, even in the face of future struct layout randomization. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-09powerpc: Don't print cpu_spec->cpu_name if it's NULLNicholas Piggin
Currently we assume that if the cpu_spec has a pvr_mask then it must also have a cpu_name. But that will change in a subsequent commit when we do CPU feature discovery via the device tree, so check explicitly if cpu_name is NULL. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-09of/fdt: introduce of_scan_flat_dt_subnodes and of_get_flat_dt_phandleNicholas Piggin
Introduce primitives for FDT parsing. These will be used for powerpc cpufeatures node scanning, which has quite complex structure but should be processed early. Cc: devicetree@vger.kernel.org Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-09Merge branch 'next' of ↵Michael Ellerman
git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next Freescale updates from Scott: "Includes a fix for a powerpc/next mm regression on 64e, a fix for a kernel hang on 64e when using a debugger inside a relocated kernel, a qman fix, and misc qe improvements."
2017-05-09Merge tag 'kvm-arm-for-v4.12-round2' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD Second round of KVM/ARM Changes for v4.12. Changes include: - A fix related to the 32-bit idmap stub - A fix to the bitmask used to deode the operands of an AArch32 CP instruction - We have moved the files shared between arch/arm/kvm and arch/arm64/kvm to virt/kvm/arm - We add support for saving/restoring the virtual ITS state to userspace
2017-05-09KVM: arm/arm64: vgic-its: Cleanup after failed ITT restoreChristoffer Dall
When failing to restore the ITT for a DTE, we should remove the failed device entry from the list and free the object. We slightly refactor vgic_its_destroy to be able to reuse the now separate vgic_its_free_dte() function. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: arm/arm64: Don't call map_resources when restoring ITS tablesChristoffer Dall
The only reason we called kvm_vgic_map_resources() when restoring the ITS tables was because we wanted to have the KVM iodevs registered in the KVM IO bus framework at the time when the ITS was restored such that a restored and active device can inject MSIs prior to otherwise calling kvm_vgic_map_resources() from the first run of a VCPU. Since we now register the KVM iodevs for the redestributors and ITS as soon as possible (when setting the base addresses), we no longer need this call and kvm_vgic_map_resources() is again called only when first running a VCPU. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: arm/arm64: Register ITS iodev when setting base addressChristoffer Dall
We have to register the ITS iodevice before running the VM, because in migration scenarios, we may be restoring a live device that wishes to inject MSIs before the VCPUs have started. All we need to register the ITS io device is the base address of the ITS, so we can simply register that when the base address of the ITS is set. [ Code to fix concurrency issues when setting the ITS base address and to fix the undef base address check written by Marc Zyngier ] Signed-off-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: arm/arm64: Get rid of its->initialized fieldMarc Zyngier
The its->initialized doesn't bring much to the table, and creates unnecessary ordering between setting the address and initializing it (which amounts to exactly nothing). Let's kill it altogether, making KVM_DEV_ARM_VGIC_CTRL_INIT the no-op it deserves to be. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUsChristoffer Dall
Instead of waiting with registering KVM iodevs until the first VCPU is run, we can actually create the iodevs when the redist base address is set. The only downside is that we must now also check if we need to do this for VCPUs which are created after creating the VGIC, because there is no enforced ordering between creating the VGIC (and setting its base addresses) and creating the VCPUs. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: arm/arm64: Slightly rework kvm_vgic_addrChristoffer Dall
As we are about to handle setting the address for the redistributor base region separately from some of the other base addresses, let's rework this function to leave a little more room for being flexible in what each type of base address does. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: arm/arm64: Make vgic_v3_check_base more broadly usableChristoffer Dall
As we are about to fiddle with the IO device registration mechanism, let's be a little more careful when setting base addresses as early as possible. When setting a base address, we can check that there's address space enough for its scope and when the last of the two base addresses (dist and redist) get set, we can also check if the regions overlap at that time. This allows us to provide error messages to the user at time when trying to set the base address, as opposed to later when trying to run the VM. To do this, we make vgic_v3_check_base available in the core vgic-v3 code as well as in the other parts of the GICv3 code, namely the MMIO config code. We also return true for undefined base addresses so that the function can be used before all base addresses are set; all callers already check for uninitialized addresses before calling this function. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: arm/arm64: Refactor vgic_register_redist_iodevsChristoffer Dall
Split out the function to register all the redistributor iodevs into a function that handles a single redistributor at a time in preparation for being able to call this per VCPU as these get created. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: Add kvm_vcpu_get_idx to get vcpu index in kvm->vcpusChristoffer Dall
There are occasional needs to use the index of vcpu in the kvm->vcpus array to map something related to a VCPU. For example, unlike the vcpu->vcpu_id, the vcpu index is guaranteed to not be sparse across all vcpus which is useful when allocating a memory area for each vcpu. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09nVMX: Advertise PML to L1 hypervisorBandan Das
Advertise the PML bit in vmcs12 but don't try to enable it in hardware when running L2 since L0 is emulating it. Also, preserve L0's settings for PML since it may still want to log writes. Signed-off-by: Bandan Das <bsd@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-09nVMX: Implement emulated Page Modification LoggingBandan Das
With EPT A/D enabled, processor access to L2 guest paging structures will result in a write violation. When this happens, write the GUEST_PHYSICAL_ADDRESS to the pml buffer provided by L1 if the access is write and the dirty bit is being set. This patch also adds necessary checks during VMEntry if L1 has enabled PML. If the PML index overflows, we change the exit reason and run L1 to simulate a PML full event. Signed-off-by: Bandan Das <bsd@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-09kvm: x86: Add a hook for arch specific dirty logging emulationBandan Das
When KVM updates accessed/dirty bits, this hook can be used to invoke an arch specific function that implements/emulates dirty logging such as PML. Signed-off-by: Bandan Das <bsd@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-09kvm: nVMX: Validate CR3 target count on nested VM-entryJim Mattson
According to the SDM, the CR3-target count must not be greater than 4. Future processors may support a different number of CR3-target values. Software should read the VMX capability MSR IA32_VMX_MISC to determine the number of values supported. Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-09Merge branch 'kvm-ppc-next' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD The main thing here is a new implementation of the in-kernel XICS interrupt controller emulation for POWER9 machines, from Ben Herrenschmidt. POWER9 has a new interrupt controller called XIVE (eXternal Interrupt Virtualization Engine) which is able to deliver interrupts directly to guest virtual CPUs in hardware without hypervisor intervention. With this new code, the guest still sees the old XICS interface but performance is better because the XICS emulation in the host uses the XIVE directly rather than going through a XICS emulation in firmware. Conflicts: arch/powerpc/kernel/cpu_setup_power.S [cherry-picked fix] arch/powerpc/kvm/book3s_xive.c [include asm/debugfs.h]
2017-05-09KVM: set no_llseek in stat_fops_per_vmGeliang Tang
In vm_stat_get_per_vm_fops and vcpu_stat_get_per_vm_fops, since we use nonseekable_open() to open, we should use no_llseek() to seek, not generic_file_llseek(). Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-09powerpc/64s: Fix unnecessary machine check handler relocation branchNicholas Piggin
Similarly to commit 2563a70c3b ("powerpc/64s: Remove unnecessary relocation branch from idle handler"), the machine check handler has a BRANCH_TO from relocated to relocated code, which is unnecessary. It has also caused build errors with some toolchains: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:395: Error: operand out of range (0xffffffffffff8280 is not between 0x0000000000000000 and 0x000000000000ffff) Fixes: 1945bc4549e5 ("powerpc/64s: Fix POWER9 machine check handler from stop state") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reported-and-tested-by : Abdul Haleem <abdhalee@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-09powerpc/mm/book3s/64: Rework page table geometry for lower memory usageMichael Ellerman
Recently in commit f6eedbba7a26 ("powerpc/mm/hash: Increase VA range to 128TB") we increased the virtual address space for user processes to 128TB by default, and up to 512TB if user space opts in. This obviously required expanding the range of the Linux page tables. For Book3s 64-bit using hash and with PAGE_SIZE=64K, we increased the PGD to 2^15 entries. This meant we could cover the full address range, while still being able to insert a 16G hugepage at the PGD level and a 16M hugepage in the PMD. The downside of that geometry is that it uses a lot of memory for the PGD, and in particular makes the PGD a 4-page allocation, which means it's much more likely to fail under memory pressure. Instead we can make the PMD larger, so that a single PUD entry maps 16G, allowing the 16G hugepages to sit at that level in the tree. We're then able to split the remaining bits between the PUG and PGD. We make the PGD slightly larger as that results in lower memory usage for typical programs. When THP is enabled the PMD actually doubles in size, to 2^11 entries, or 2^14 bytes, which is large but still < PAGE_SIZE. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2017-05-09powerpc: Fix distclean with Makefile.postlinkHoria Geantă
Makefile.postlink always includes include/config/auto.conf, however this file is not present in a clean kernel tree, causing make to fail: $ git clone linuxppc.git $ cd linuxppc.git $ make distclean arch/powerpc/Makefile.postlink:10: include/config/auto.conf: No such file or directory make[1]: *** No rule to make target `include/config/auto.conf'. Stop. make: *** [vmlinuxclean] Error 2 Equally running 'make distclean; make distclean' will trip the error case. Change the inclusion such that file not being found does not trigger an error. Fixes: f188d0524d7e ("powerpc: Use the new post-link pass to check relocations") Reported-by: Mircea Pop <mircea.pop@nxp.com> Signed-off-by: Horia Geantă <horia.geanta@nxp.com> Tested-by: Justin M. Forbes <jforbes@fedoraproject.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-09KVM: arm/arm64: vgic: Rename kvm_vgic_vcpu_init to kvm_vgic_vcpu_enableChristoffer Dall
This function really doesn't init anything, it enables the CPU interface, so name it as such, which gives us the name to use for actual init work later on. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09KVM: arm/arm64: Clarification and relaxation to ITS save/restore ABIChristoffer Dall
Clarify what is meant by the save/restore ABI only supporting virtual physical interrupts. Relax the requirement of the order that the collection entries are written in and be clear that there is no particular ordering enforced. Some cosmetic changes in the capitalization of ID names to align with the GICv3 manual and remove the empty line in the bottom of the patch. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Eric Auger <eric.auger@redhat.com>
2017-05-09s390: move _text symbol to address higher than zeroHeiko Carstens
The perf tool assumes that kernel symbols are never present at address zero. In fact it assumes if functions that map symbols to addresses return zero, that the symbol was not found. Given that s390's _text symbol historically is located at address zero this yields at least a couple of false errors and warnings in one of perf's test cases about not present symbols ("perf test 1"). To fix this simply move the _text symbol to address 0x200, just behind the initial psw and channel program located at the beginning of the kernel image. This is now hard coded within the linker script. I tried a nicer solution which moves the initial psw and channel program into an own section. However that would move the symbols within the "real" head.text section to different addresses, since the ".org" statements within head.S are relative to the head.text section. If there is a new section in front, everything else will be moved. Alternatively I could have adjusted all ".org" statements. But this current solution seems to be the easiest one, since nobody really cares where the _text symbol is actually located. Reported-by: Zvonko Kosic <zkosic@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-09s390/qdio: increase string buffer sizeHeiko Carstens
Avoid false positive warnings like this with gcc 7.1: drivers/s390/cio/qdio_debug.h:63:4: note: 'snprintf' output between 8 and 17 bytes into a destination of size 16 snprintf(debug_buffer, QDIO_DBF_LEN, text); and simply increase the size of the string buffer. Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-09s390/ccwgroup: increase string buffer sizeHeiko Carstens
Avoid false positive warnings like this with gcc 7.1: drivers/s390/cio/ccwgroup.c:41:21: warning: '%d' directive writing between 1 and 10 bytes into a region of size 4 sprintf(str, "cdev%d", i); and simply increase the size of the string buffer. Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-09s390/topology: let topology_mnest_limit() return unsigned charHeiko Carstens
Fixes a couple of compile warnings with gcc 7.1.0 : arch/s390/kernel/sysinfo.c:578:20: note: directive argument in the range [-2147483648, 4] sprintf(link_to, "15_1_%d", topology_mnest_limit()); Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-09s390/uaccess: use sane length for __strncpy_from_user()Heiko Carstens
The average string that is copied from user space to kernel space is rather short. E.g. booting a system involves about 50.000 strncpy_from_user() calls where the NULL terminated string has an average size of 27 bytes. By default our s390 specific strncpy_from_user() implementation however copies up to 4096 bytes, which is a waste of cpu cycles and cache lines. Therefore reduce the default length to L1_CACHE_BYTES (256 bytes), which also reduces the average execution time of strncpy_from_user() by 30-40%. Alternatively we could have switched to the generic strncpy_from_user() implementation, however it turned out that that variant would be slower than the now optimized s390 variant. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-09x86/intel_rdt: Fix a typo in DocumentationXiaochen Shen
Example 3 contains a typo: "C0" in "# echo C0 > p0/cpus" is wrong because it specifies core 6-7 instead of wanted core 4-7. Correct this typo to avoid confusion. Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Acked-by: Fenghua Yu <fenghua.yu@intel.com> Cc: vikas.shivappa@linux.intel.com Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1493781356-24229-1-git-send-email-xiaochen.shen@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-05-09clocksource/arm_arch_timer: Fix arch_timer_mem_find_best_frame()Sudeep Holla
arch_timer_mem_find_best_frame() looks through ARCH_TIMER_MEM_MAX_FRAMES frames even after finding matches to ensure the best frame is chosen, which means the variable frame will point to the last valid frame but not necessarily the best frame. On Juno, we get the following error as the wrong frame is returned as the best frame from arch_timer_mem_find_best_frame(): arch_timer: Unable to map frame @ 0x0000000000000000 arch_timer: Frame missing phys irq. Failed to initialize '/timer@2a810000': -22 Fix the issue by correctly returning the best frame from arch_timer_mem_find_best_frame(). Fixes: c389d701dfb7 ("clocksource: arm_arch_timer: split MMIO timer probing.") Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1494246747-17267-1-git-send-email-sudeep.holla@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>