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* Merge branch 'akpm' (patches from Andrew)Linus Torvalds2020-04-113-6/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge yet more updates from Andrew Morton: - Almost all of the rest of MM (memcg, slab-generic, slab, pagealloc, gup, hugetlb, pagemap, memremap) - Various other things (hfs, ocfs2, kmod, misc, seqfile) * akpm: (34 commits) ipc/util.c: sysvipc_find_ipc() should increase position index kernel/gcov/fs.c: gcov_seq_next() should increase position index fs/seq_file.c: seq_read(): add info message about buggy .next functions drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings change email address for Pali Rohár selftests: kmod: test disabling module autoloading selftests: kmod: fix handling test numbers above 9 docs: admin-guide: document the kernel.modprobe sysctl fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() kmod: make request_module() return an error when autoloading is disabled mm/memremap: set caching mode for PCI P2PDMA memory to WC mm/memory_hotplug: add pgprot_t to mhp_params powerpc/mm: thread pgprot_t through create_section_mapping() x86/mm: introduce __set_memory_prot() x86/mm: thread pgprot_t through init_memory_mapping() mm/memory_hotplug: rename mhp_restrictions to mhp_params mm/memory_hotplug: drop the flags field from struct mhp_restrictions mm/special: create generic fallbacks for pte_special() and pte_mkspecial() mm/vma: introduce VM_ACCESS_FLAGS mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS ...
| * mm/memory_hotplug: add pgprot_t to mhp_paramsLogan Gunthorpe2020-04-111-0/+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 <logang@deltatee.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Badger <ebadger@gigaio.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200306170846.9333-7-logang@deltatee.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * mm/memory_hotplug: rename mhp_restrictions to mhp_paramsLogan Gunthorpe2020-04-111-3/+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 <logang@deltatee.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Badger <ebadger@gigaio.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200306170846.9333-3-logang@deltatee.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * mm/vma: introduce VM_ACCESS_FLAGSAnshuman Khandual2020-04-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are many places where all basic VMA access flags (read, write, exec) are initialized or checked against as a group. One such example is during page fault. Existing vma_is_accessible() wrapper already creates the notion of VMA accessibility as a group access permissions. Hence lets just create VM_ACCESS_FLAGS (VM_READ|VM_WRITE|VM_EXEC) which will not only reduce code duplication but also extend the VMA accessibility concept in general. Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Salter <msalter@redhat.com> Cc: Nick Hu <nickhu@andestech.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Springer <rspringer@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Link: http://lkml.kernel.org/r/1583391014-8170-3-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * mm/vma: define a default value for VM_DATA_DEFAULT_FLAGSAnshuman Khandual2020-04-111-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the existing VM_STACK_DEFAULT_FLAGS. While here, also define some more macros with standard VMA access flag combinations that are used frequently across many platforms. Apart from simplification, this reduces code duplication as well. Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Salter <msalter@redhat.com> Cc: Guo Ren <guoren@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Brian Cain <bcain@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paulburton@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Rich Felker <dalias@libc.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jeff Dike <jdike@addtoit.com> Cc: Chris Zankel <chris@zankel.net> Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 's390-5.7-2' of ↵Linus Torvalds2020-04-102-10/+8
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull more s390 updates from Vasily Gorbik: "Second round of s390 fixes and features for 5.7: - The rest of fallthrough; annotations conversion - Couple of fixes for ADD uevents in the common I/O layer - Minor refactoring of the queued direct I/O code" * tag 's390-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/cio: generate delayed uevent for vfio-ccw subchannels s390/cio: avoid duplicated 'ADD' uevents s390/qdio: clear DSCI early for polling drivers s390/qdio: inline shared_ind() s390/qdio: remove cdev from init_data s390/qdio: allow for non-contiguous SBAL array in init_data zfcp: inline zfcp_qdio_setup_init_data() s390/qdio: cleanly split alloc and establish s390/mm: use fallthrough;
| * s390/qdio: remove cdev from init_dataJulian Wiedmann2020-04-061-3/+2
| | | | | | | | | | | | | | | | It's no longer needed. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * s390/qdio: allow for non-contiguous SBAL array in init_dataJulian Wiedmann2020-04-061-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Upper-layer drivers allocate their SBALs by calling qdio_alloc_buffers() for each individual queue. But when later passing the SBAL addresses to qdio_establish(), they need to be in a single array of pointers. So if the driver uses multiple Input or Output queues, it needs to allocate a temporary array just to present all its SBAL pointers in this layout. This patch slightly changes the format of the QDIO initialization data, so that drivers can pass a per-queue array where each element points to a queue's SBAL array. zfcp doesn't use multiple queues, so the impact there is trivial. For qeth this brings a nice reduction in complexity, and removes a page-sized allocation. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * s390/qdio: cleanly split alloc and establishJulian Wiedmann2020-04-061-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | All that qdio_allocate() actually uses from the init_data is the cdev, and the number of Input and Output Queues. Have the driver pass those as parameters, and defer the init_data processing into qdio_establish(). This includes writing per-device(!) trace entries, and most of the sanity checks. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * s390/mm: use fallthrough;Joe Perches2020-04-061-2/+0
| | | | | | | | | | | | | | | | | | | | | | Convert the various uses of fallthrough comments to fallthrough; Done via script Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe.com/ Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2020-04-082-1/+7
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more kvm updates from Paolo Bonzini: "s390: - nested virtualization fixes x86: - split svm.c - miscellaneous fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: VMX: fix crash cleanup when KVM wasn't used KVM: X86: Filter out the broadcast dest for IPI fastpath KVM: s390: vsie: Fix possible race when shadowing region 3 tables KVM: s390: vsie: Fix delivery of addressing exceptions KVM: s390: vsie: Fix region 1 ASCE sanity shadow address checks KVM: nVMX: don't clear mtf_pending when nested events are blocked KVM: VMX: Remove unnecessary exception trampoline in vmx_vmenter KVM: SVM: Split svm_vcpu_run inline assembly to separate file KVM: SVM: Move SEV code to separate file KVM: SVM: Move AVIC code to separate file KVM: SVM: Move Nested SVM Implementation to nested.c kVM SVM: Move SVM related files to own sub-directory
| * | KVM: s390: vsie: Fix possible race when shadowing region 3 tablesDavid Hildenbrand2020-04-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have to properly retry again by returning -EINVAL immediately in case somebody else instantiated the table concurrently. We missed to add the goto in this function only. The code now matches the other, similar shadowing functions. We are overwriting an existing region 2 table entry. All allocated pages are added to the crst_list to be freed later, so they are not lost forever. However, when unshadowing the region 2 table, we wouldn't trigger unshadowing of the original shadowed region 3 table that we replaced. It would get unshadowed when the original region 3 table is modified. As it's not connected to the page table hierarchy anymore, it's not going to get used anymore. However, for a limited time, this page table will stick around, so it's in some sense a temporary memory leak. Identified by manual code inspection. I don't think this classifies as stable material. Fixes: 998f637cc4b9 ("s390/mm: avoid races on region/segment/page table shadowing") Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200403153050.20569-4-david@redhat.com Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: vsie: Fix delivery of addressing exceptionsDavid Hildenbrand2020-04-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Whenever we get an -EFAULT, we failed to read in guest 2 physical address space. Such addressing exceptions are reported via a program intercept to the nested hypervisor. We faked the intercept, we have to return to guest 2. Instead, right now we would be returning -EFAULT from the intercept handler, eventually crashing the VM. the correct thing to do is to return 1 as rc == 1 is the internal representation of "we have to go back into g2". Addressing exceptions can only happen if the g2->g3 page tables reference invalid g2 addresses (say, either a table or the final page is not accessible - so something that basically never happens in sane environments. Identified by manual code inspection. Fixes: a3508fbe9dc6 ("KVM: s390: vsie: initial support for nested virtualization") Cc: <stable@vger.kernel.org> # v4.8+ Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200403153050.20569-3-david@redhat.com Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [borntraeger@de.ibm.com: fix patch description] Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * | KVM: s390: vsie: Fix region 1 ASCE sanity shadow address checksDavid Hildenbrand2020-04-071-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case we have a region 1 the following calculation (31 + ((gmap->asce & _ASCE_TYPE_MASK) >> 2)*11) results in 64. As shifts beyond the size are undefined the compiler is free to use instructions like sllg. sllg will only use 6 bits of the shift value (here 64) resulting in no shift at all. That means that ALL addresses will be rejected. The can result in endless loops, e.g. when prefix cannot get mapped. Fixes: 4be130a08420 ("s390/mm: add shadow gmap support") Tested-by: Janosch Frank <frankja@linux.ibm.com> Reported-by: Janosch Frank <frankja@linux.ibm.com> Cc: <stable@vger.kernel.org> # v4.8+ Signed-off-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200403153050.20569-2-david@redhat.com Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [borntraeger@de.ibm.com: fix patch description, remove WARN_ON_ONCE] Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | | Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds2020-04-081-4/+0
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull virtio updates from Michael Tsirkin: - Some bug fixes - The new vdpa subsystem with two first drivers * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio-balloon: Revert "virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM" vdpa: move to drivers/vdpa virtio: Intel IFC VF driver for VDPA vdpasim: vDPA device simulator vhost: introduce vDPA-based backend virtio: introduce a vDPA based transport vDPA: introduce vDPA bus vringh: IOTLB support vhost: factor out IOTLB vhost: allow per device message handler vhost: refine vhost and vringh kconfig virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM virtio-net: Introduce hash report feature virtio-net: Introduce RSS receive steering feature virtio-net: Introduce extended RSC feature tools/virtio: option to build an out of tree module
| * | vhost: refine vhost and vringh kconfigJason Wang2020-04-011-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is not necessarily for VM since it's a generic userspace and kernel communication protocol. Such dependency may prevent archs without virtualization support from using vhost. To solve this, a dedicated vhost menu is created under drivers so CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION. While at it, also squash Kconfig.vringh into vhost Kconfig file. This avoids the trick of conditional inclusion from VOP or CAIF. Then it will be easier to introduce new vringh users and common dependency for both vringh and vhost. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* | | Merge tag 's390-5.7-1' of ↵Linus Torvalds2020-04-0452-2176/+551
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Update maintainers. Niklas Schnelle takes over zpci and Vineeth Vijayan common io code. - Extend cpuinfo to include topology information. - Add new extended counters for IBM z15 and sampling buffer allocation rework in perf code. - Add control over zeroing out memory during system restart. - CCA protected key block version 2 support and other fixes/improvements in crypto code. - Convert to new fallthrough; annotations. - Replace zero-length arrays with flexible-arrays. - QDIO debugfs and other small improvements. - Drop 2-level paging support optimization for compat tasks. Varios mm cleanups. - Remove broken and unused hibernate / power management support. - Remove fake numa support which does not bring any benefits. - Exclude offline CPUs from CPU topology masks to be more consistent with other architectures. - Prevent last branching instruction address leaking to userspace. - Other small various fixes and improvements all over the code. * tag 's390-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (57 commits) s390/mm: cleanup init_new_context() callback s390/mm: cleanup virtual memory constants usage s390/mm: remove page table downgrade support s390/qdio: set qdio_irq->cdev at allocation time s390/qdio: remove unused function declarations s390/ccwgroup: remove pm support s390/ap: remove power management code from ap bus and drivers s390/zcrypt: use kvmalloc instead of kmalloc for 256k alloc s390/mm: cleanup arch_get_unmapped_area() and friends s390/ism: remove pm support s390/cio: use fallthrough; s390/vfio: use fallthrough; s390/zcrypt: use fallthrough; s390: use fallthrough; s390/cpum_sf: Fix wrong page count in error message s390/diag: fix display of diagnose call statistics s390/ap: Remove ap device suspend and resume callbacks s390/pci: Improve handling of unset UID s390/pci: Fix zpci_alloc_domain() over allocation s390/qdio: pass ISC as parameter to chsc_sadc() ...
| * | | s390/mm: cleanup init_new_context() callbackAlexander Gordeev2020-03-282-25/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The set of values asce_limit may be assigned with is TASK_SIZE_MAX, _REGION1_SIZE, _REGION2_SIZE and 0 as a special case if the callback was called from execve(). Do VM_BUG_ON() if asce_limit is something else. Save few CPU cycles by removing unnecessary asce_limit re-assignment in case of 3-level task and redundant PGD entry type reconstruction. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/mm: cleanup virtual memory constants usageAlexander Gordeev2020-03-283-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove duplicate definitions and consolidate usage of virutal and address translation constants. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/mm: remove page table downgrade supportAlexander Gordeev2020-03-285-47/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This update consolidates page table handling code. Because there are hardly any 31-bit binaries left we do not need to optimize for that. No extra efforts are needed to ensure that a compat task does not map anything above 2GB. The TASK_SIZE limit for 31-bit tasks is 2GB already and the generic code does check that a resulting map address would not surpass that limit. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/mm: cleanup arch_get_unmapped_area() and friendsAlexander Gordeev2020-03-273-38/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Factor out check_asce_limit() function and fix few style defects in arch_get_unmapped_area() family of functions. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> [heiko.carstens@de.ibm.com: small coding style changes] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390: use fallthrough;Joe Perches2020-03-254-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert the various uses of fallthrough comments to fallthrough; Done via script Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe.com/ Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/cpum_sf: Fix wrong page count in error messageThomas Richter2020-03-251-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When perf record -e SF_CYCLES_BASIC_DIAG runs with very high frequency, the samples arrive faster than the perf process can save them to file. Eventually, for longer running processes, this leads to the siutation where the trace buffers allocated by perf slowly fills up. At one point the auxiliary trace buffer is full and the CPU Measurement sampling facility is turned off. Furthermore a warning is printed to the kernel log buffer: cpum_sf: The AUX buffer with 0 pages for the diagnostic-sampling mode is full The number of allocated pages for the auxiliary trace buffer is shown as zero pages. That is wrong. Fix this by saving the number of allocated pages before entering the work loop in the interrupt handler. When the interrupt handler processes the samples, it may detect the buffer full condition and stop sampling, reducing the buffer size to zero. Print the correct value in the error message: cpum_sf: The AUX buffer with 256 pages for the diagnostic-sampling mode is full Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/diag: fix display of diagnose call statisticsMichael Mueller2020-03-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Show the full diag statistic table and not just parts of it. The issue surfaced in a KVM guest with a number of vcpus defined smaller than NR_DIAG_STAT. Fixes: 1ec2772e0c3c ("s390/diag: add a statistic for diagnose calls") Cc: stable@vger.kernel.org Signed-off-by: Michael Mueller <mimu@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/pci: Improve handling of unset UIDNiklas Schnelle2020-03-233-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When UID checking is enabled a UID value of 0 is invalid and can not be set by the user. On z/VM it is however used to indicate an unset UID. Until now, this lead to the behavior that one PCI function could be attached with UID 0 after which z/VM would prohibit further attachment. Now if the user then turns off UID checking in z/VM the user could seemingly attach additional PCI functions that would however not show up in Linux as that would not be informed of the change in UID checking mode. This is unexpected and confusing and lead to bug reports against Linux. Instead now, if we encounter an unset UID value of 0 treat it as indicating that UID checking was turned off, switch to automatic domain allocation, and warn the user of the possible misconfiguration. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/pci: Fix zpci_alloc_domain() over allocationNiklas Schnelle2020-03-232-16/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Until now zpci_alloc_domain() only prevented more than CONFIG_PCI_NR_FUNCTIONS from being added when using automatic domain allocation. When explicit UIDs were defined UIDs above CONFIG_PCI_NR_FUNCTIONS were not counted at all. When more PCI functions are added this could lead to various errors including under sized IRQ vectors and similar issues. Fix this by explicitly tracking the number of allocated domains. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390: remove broken hibernate / power management supportHeiko Carstens2020-03-238-660/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hibernation is known to be broken for many years on s390. Given that there aren't any real use cases, remove the code instead of spending time to fix and maintain it. Without hibernate support it doesn't make too much sense to keep power management support; therefore remove it completely. Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/cpuinfo: do not skip info for CPUs without MHz featureAlexander Gordeev2020-03-231-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the past there were no per-CPU information in /proc/cpuinfo other than CPU frequency. Hence, for machines without CPU MHz feature there were nothing to show. Now CPU topology and IDs still could be shown, so do not skip this information from the output. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> [heiko.carstens@de.ibm.com: moved comparison] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/cpuinfo: fix wrong output when CPU0 is offlineAlexander Gordeev2020-03-231-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | /proc/cpuinfo should not print information about CPU 0 when it is offline. Fixes: 281eaa8cb67c ("s390/cpuinfo: simplify locking and skip offline cpus early") Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> [heiko.carstens@de.ibm.com: shortened commit message] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/cpuinfo: show number of online CPUs within a packageAlexander Gordeev2020-03-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Show number of online CPUs within a package (which is the socket in case of s390). For what it worth, present that value as "siblings" field - just like x86 does. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/cpuinfo: show number of online coresAlexander Gordeev2020-03-233-2/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Show number of cores that run at least one SMT thread Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/ipl: add support to control memory clearing for FCP and CCW re-IPLGerald Schaefer2020-03-232-7/+67
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Re-IPL for both CCW and FCP is currently done by using diag 308 with the "Load Clear" subcode, which means that all memory will be cleared. This can increase re-IPL duration considerably on very large machines. For CCW devices, there is also a "Load Normal" subcode that was only used for dump kernels so far. For FCP devices, a similar "Load Normal" subcode was introduced with z14. The "Load Normal" diag 308 subcode allows to re-IPL without clearing memory. This patch adds a new "clear" sysfs attribute to /sys/firmware/reipl for both the ccw and fcp subdirectories, which can be set to either "0" or "1" to disable or enable re-IPL with memory clearing. The default value is "0", which disables memory clearing. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/topology: remove offline CPUs from CPU topology masksAlexander Gordeev2020-03-233-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The CPU topology masks on s390 contain also bits of CPUs which are offline. Currently this is already a problem, since common code scheduler expects e.g. cpu_smt_mask() to reflect reality. This update changes the described behaviour and s390 starts to behave like all other architectures. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/numa: remove redundant cpus_with_topology variableAlexander Gordeev2020-03-232-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Variable cpus_with_topology is a leftover that became unneeded once the fake NUMA support has been removed. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/cpuinfo: show processor physical addressAlexander Gordeev2020-03-233-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Show CPU physical address as reported by STAP instruction Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/mm: optimize page table upgrade routineAlexander Gordeev2020-03-231-34/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a maximum of two new tables allocated on page table upgrade. Because we know that a loop the current implementation is based on could be unrolled with some improvements: * upgrade from 3 to 5 levels happens in one go - without an unnecessary re-take of page_table_lock in-between; * page tables initialization moved out of the atomic code; Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/config: do not select VIRTIO_CONSOLE via KconfigChristian Borntraeger2020-03-113-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | select does not ensure that dependencies are also selected. Instead of selecting VIRTIO_CONSOLE from S390_GUEST we should rather add this to the defconfigs. So we update those as well. Reported-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/traps: mark test_monitor_call __initHeiko Carstens2020-03-111-1/+1
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/irq: make init_ext_interrupts staticHeiko Carstens2020-03-112-10/+9
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/irq: replace setup_irq() by request_irq()afzal mohammed2020-03-111-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | request_irq() is preferred over setup_irq(). Invocations of setup_irq() occur after memory allocators are ready. Per tglx[1], setup_irq() existed in olden days when allocators were not ready by the time early interrupts were initialized. Hence replace setup_irq() by request_irq(). [1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com> Message-Id: <20200304005049.5291-1-afzal.mohd.ma@gmail.com> [heiko.carstens@de.ibm.com: replace pr_err with panic] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/cpuinfo: add system topology informationAlexander Gordeev2020-03-101-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This update adjusts /proc/cpuinfo format to meet some user level programs expectations. It also makes the layout consistent with x86 where CPU topology is presented as blocks of key-value pairs. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390: prevent leaking kernel address in BEARSven Schnelle2020-03-109-27/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When userspace executes a syscall or gets interrupted, BEAR contains a kernel address when returning to userspace. This make it pretty easy to figure out where the kernel is mapped even with KASLR enabled. To fix this, add lpswe to lowcore and always execute it there, so userspace sees only the lowcore address of lpswe. For this we have to extend both critical_cleanup and the SWITCH_ASYNC macro to also check for lpswe addresses in lowcore. Fixes: b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)") Cc: <stable@vger.kernel.org> # v5.2+ Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390: enable bpf jit by default when not built as always-onHeiko Carstens2020-03-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the s390 variant of commit 81c22041d9f1 ("bpf, x86, arm64: Enable jit by default when not built as always-on"). Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/cpum_cf: Add new extended counters for IBM z15Thomas Richter2020-03-101-1/+122
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add CPU measurement counter facility event description for IBM z15. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/pci: embedding hotplug_slot in zdevPierre Morel2020-03-101-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Embedding the hotplug_slot in zdev structure allows to greatly simplify the hotplug handling by eliminating the handling of the slot_list. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/mm: cleanup phys_to_pfn() and friendsAlexander Gordeev2020-03-061-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make page, frame, virtual and physical address conversion macros more expressive by avoiding redundant definitions and defining new macros using existing ones. Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/mm: mark private defines for vm_fault_t as suchChristian Borntraeger2020-03-041-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes several sparse warnings for fault.c: arch/s390/mm/fault.c:336:36: warning: restricted vm_fault_t degrades to integer arch/s390/mm/fault.c:573:23: warning: incorrect type in assignment (different base types) arch/s390/mm/fault.c:573:23: expected restricted vm_fault_t [usertype] fault arch/s390/mm/fault.c:573:23: got int Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/mm: remove fake numa supportHeiko Carstens2020-02-2711-1230/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It turned out that fake numa support is rather useless on s390, since there are no scenarios where there is any performance or other benefit when used. However it does provide maintenance cost and breaks from time to time. Therefore remove it. CONFIG_NUMA is still supported with a very small backend and only one node. This way userspace applications which require NUMA interfaces continue to work. Note that NODES_SHIFT is set to 1 (= 2 nodes) instead of 0 (= 1 node), since there is quite a bit of kernel code which assumes that more than one node is possible if CONFIG_NUMA is enabled. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390/crypto: explicitly memzero stack key material in aes_s390.cTorsten Duwe2020-02-271-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | aes_s390.c has several functions which allocate space for key material on the stack and leave the used keys there. It is considered good practice to clean these locations before the function returns. Link: https://lkml.kernel.org/r/20200221165511.GB6928@lst.de Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Harald Freudenberger <freude@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| * | | s390: Replace zero-length array with flexible-array memberGustavo A. R. Silva2020-02-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Link: https://lkml.kernel.org/r/20200221150612.GA9717@embeddedor Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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