summaryrefslogtreecommitdiff
AgeCommit message (Collapse)Author
2020-04-21KVM: x86: Drop @invalidate_gpa param from kvm_x86_ops' tlb_flush()Sean Christopherson
Drop @invalidate_gpa from ->tlb_flush() and kvm_vcpu_flush_tlb() now that all callers pass %true for said param, or ignore the param (SVM has an internal call to svm_flush_tlb() in svm_flush_tlb_guest that somewhat arbitrarily passes %false). Remove __vmx_flush_tlb() as it is no longer used. No functional change intended. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-17-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-21KVM: VMX: Clean up vmx_flush_tlb_gva()Sean Christopherson
Refactor vmx_flush_tlb_gva() to remove a superfluous local variable and clean up its comment, which is oddly located below the code it is commenting. No functional change intended. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-16-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-21KVM: x86: make Hyper-V PV TLB flush use tlb_flush_guest()Vitaly Kuznetsov
Hyper-V PV TLB flush mechanism does TLB flush on behalf of the guest so doing tlb_flush_all() is an overkill, switch to using tlb_flush_guest() (just like KVM PV TLB flush mechanism) instead. Introduce KVM_REQ_HV_TLB_FLUSH to support the change. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-21KVM: PPC: Book3S HV: Handle non-present PTEs in page fault functionsPaul Mackerras
Since cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT page fault handler", it's been possible in fairly rare circumstances to load a non-present PTE in kvmppc_book3s_hv_page_fault() when running a guest on a POWER8 host. Because that case wasn't checked for, we could misinterpret the non-present PTE as being a cache-inhibited PTE. That could mismatch with the corresponding hash PTE, which would cause the function to fail with -EFAULT a little further down. That would propagate up to the KVM_RUN ioctl() generally causing the KVM userspace (usually qemu) to fall over. This addresses the problem by catching that case and returning to the guest instead. For completeness, this fixes the radix page fault handler in the same way. For radix this didn't cause any obvious misbehaviour, because we ended up putting the non-present PTE into the guest's partition-scoped page tables, leading immediately to another hypervisor data/instruction storage interrupt, which would go through the page fault path again and fix things up. Fixes: cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT page fault handler" Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1820402 Reported-by: David Gibson <david@gibson.dropbear.id.au> Tested-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-04-20KVM: x86: Move "flush guest's TLB" logic to separate kvm_x86_ops hookSean Christopherson
Add a dedicated hook to handle flushing TLB entries on behalf of the guest, i.e. for a paravirtualized TLB flush, and use it directly instead of bouncing through kvm_vcpu_flush_tlb(). For VMX, change the effective implementation implementation to never do INVEPT and flush only the current context, i.e. to always flush via INVVPID(SINGLE_CONTEXT). The INVEPT performed by __vmx_flush_tlb() when @invalidate_gpa=false and enable_vpid=0 is unnecessary, as it will only flush guest-physical mappings; linear and combined mappings are flushed by VM-Enter when VPID is disabled, and changes in the guest pages tables do not affect guest-physical mappings. When EPT and VPID are enabled, doing INVVPID is not required (by Intel's architecture) to invalidate guest-physical mappings, i.e. TLB entries that cache guest-physical mappings can live across INVVPID as the mappings are associated with an EPTP, not a VPID. The intent of @invalidate_gpa is to inform vmx_flush_tlb() that it must "invalidate gpa mappings", i.e. do INVEPT and not simply INVVPID. Other than nested VPID handling, which now calls vpid_sync_context() directly, the only scenario where KVM can safely do INVVPID instead of INVEPT (when EPT is enabled) is if KVM is flushing TLB entries from the guest's perspective, i.e. is only required to invalidate linear mappings. For SVM, flushing TLB entries from the guest's perspective can be done by flushing the current ASID, as changes to the guest's page tables are associated only with the current ASID. Adding a dedicated ->tlb_flush_guest() paves the way toward removing @invalidate_gpa, which is a potentially dangerous control flag as its meaning is not exactly crystal clear, even for those who are familiar with the subtleties of what mappings Intel CPUs are/aren't allowed to keep across various invalidation scenarios. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-15-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: nVMX: Use vpid_sync_vcpu_addr() to emulate INVVPID with addressSean Christopherson
Use vpid_sync_vcpu_addr() to emulate the "individual address" variant of INVVPID now that said function handles the fallback case of the (host) CPU not supporting "individual address". Note, the "vpid == 0" checks in the vpid_sync_*() helpers aren't actually redundant with the "!operand.vpid" check in handle_invvpid(), as the vpid passed to vpid_sync_vcpu_addr() is a KVM (host) controlled value, i.e. vpid02 can be zero even if operand.vpid is non-zero. No functional change intended. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-14-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: VMX: Drop redundant capability checks in low level INVVPID helpersSean Christopherson
Remove the INVVPID capabilities checks from vpid_sync_vcpu_single() and vpid_sync_vcpu_global() now that all callers ensure the INVVPID variant is supported. Note, in some cases the guarantee is provided in concert with hardware_setup(), which enables VPID if and only if at least of invvpid_single() or invvpid_global() is supported. Drop the WARN_ON_ONCE() from vmx_flush_tlb() as vpid_sync_vcpu_single() will trigger a WARN() on INVVPID failure, i.e. if SINGLE_CONTEXT isn't supported. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-13-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: VMX: Handle INVVPID fallback logic in vpid_sync_vcpu_addr()Sean Christopherson
Directly invoke vpid_sync_context() to do a global INVVPID when the individual address variant is not supported instead of deferring such behavior to the caller. This allows for additional consolidation of code as the logic is basically identical to the emulation of the individual address variant in handle_invvpid(). No functional change intended. Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-12-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: VMX: Move vpid_sync_vcpu_addr() down a few linesSean Christopherson
Move vpid_sync_vcpu_addr() below vpid_sync_context() so that it can be refactored in a future patch to call vpid_sync_context() directly when the "individual address" INVVPID variant isn't supported. No functional change intended. Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-11-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: VMX: Use vpid_sync_context() directly when possibleSean Christopherson
Use vpid_sync_context() directly for flows that run if and only if enable_vpid=1, or more specifically, nested VMX flows that are gated by vmx->nested.msrs.secondary_ctls_high.SECONDARY_EXEC_ENABLE_VPID being set, which is allowed if and only if enable_vpid=1. Because these flows call __vmx_flush_tlb() with @invalidate_gpa=false, the if-statement that decides between INVEPT and INVVPID will always go down the INVVPID path, i.e. call vpid_sync_context() because "enable_ept && (invalidate_gpa || !enable_vpid)" always evaluates false. This helps pave the way toward removing @invalidate_gpa and @vpid from __vmx_flush_tlb() and its callers. Opportunstically drop unnecessary brackets in handle_invvpid() around an affected __vmx_flush_tlb()->vpid_sync_context() conversion. No functional change intended. Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-10-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: VMX: Skip global INVVPID fallback if vpid==0 in vpid_sync_context()Sean Christopherson
Skip the global INVVPID in the unlikely scenario that vpid==0 and the SINGLE_CONTEXT variant of INVVPID is unsupported. If vpid==0, there's no need to INVVPID as it's impossible to do VM-Enter with VPID enabled and vmcs.VPID==0, i.e. there can't be any TLB entries for the vCPU with vpid==0. The fact that the SINGLE_CONTEXT variant isn't supported is irrelevant. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-9-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: x86: Sync SPTEs when injecting page/EPT fault into L1Junaid Shahid
When injecting a page fault or EPT violation/misconfiguration, KVM is not syncing any shadow PTEs associated with the faulting address, including those in previous MMUs that are associated with L1's current EPTP (in a nested EPT scenario), nor is it flushing any hardware TLB entries. All this is done by kvm_mmu_invalidate_gva. Page faults that are either !PRESENT or RSVD are exempt from the flushing, as the CPU is not allowed to cache such translations. Signed-off-by: Junaid Shahid <junaids@google.com> Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200320212833.3507-8-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: x86: cleanup kvm_inject_emulated_page_faultPaolo Bonzini
To reconstruct the kvm_mmu to be used for page fault injection, we can simply use fault->nested_page_fault. This matches how fault->nested_page_fault is assigned in the first place by FNAME(walk_addr_generic). Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20KVM: x86: introduce kvm_mmu_invalidate_gvaPaolo Bonzini
Wrap the combination of mmu->invlpg and kvm_x86_ops->tlb_flush_gva into a new function. This function also lets us specify the host PGD to invalidate and also the MMU, both of which will be useful in fixing and simplifying kvm_inject_emulated_page_fault. A nested guest's MMU however has g_context->invlpg == NULL. Instead of setting it to nonpaging_invlpg, make kvm_mmu_invalidate_gva the only entry point to mmu->invlpg and make a NULL invlpg pointer equivalent to nonpaging_invlpg, saving a retpoline. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20kvm: Disable objtool frame pointer checking for vmenter.SJosh Poimboeuf
Frame pointers are completely broken by vmenter.S because it clobbers RBP: arch/x86/kvm/svm/vmenter.o: warning: objtool: __svm_vcpu_run()+0xe4: BP used as a scratch register That's unavoidable, so just skip checking that file when frame pointers are configured in. On the other hand, ORC can handle that code just fine, so leave objtool enabled in the !FRAME_POINTER case. Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Message-Id: <01fae42917bacad18be8d2cbc771353da6603473.1587398610.git.jpoimboe@redhat.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Fixes: 199cd1d7b534 ("KVM: SVM: Split svm_vcpu_run inline assembly to separate file") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-04-20MAINTAINERS: add a reviewer for KVM/s390Claudio Imbrenda
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cohuck@redhat.com> Acked-by: Janosch Frank <frankja@linux.ibm.com> Link: https://lore.kernel.org/r/20200417152936.772256-1-imbrenda@linux.ibm.com
2020-04-20KVM: s390: Fix PV check in deliverable_irqs()Eric Farman
The diag 0x44 handler, which handles a directed yield, goes into a a codepath that does a kvm_for_each_vcpu() and ultimately deliverable_irqs(). The new check for kvm_s390_pv_cpu_is_protected() contains an assertion that the vcpu->mutex is held, which isn't going to be the case in this scenario. The result is a plethora of these messages if the lock debugging is enabled, and thus an implication that we have a problem. WARNING: CPU: 9 PID: 16167 at arch/s390/kvm/kvm-s390.h:239 deliverable_irqs+0x1c6/0x1d0 [kvm] ...snip... Call Trace: [<000003ff80429bf2>] deliverable_irqs+0x1ca/0x1d0 [kvm] ([<000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm]) [<000003ff8042ba82>] kvm_s390_vcpu_has_irq+0x2a/0xa8 [kvm] [<000003ff804101e2>] kvm_arch_dy_runnable+0x22/0x38 [kvm] [<000003ff80410284>] kvm_vcpu_on_spin+0x8c/0x1d0 [kvm] [<000003ff80436888>] kvm_s390_handle_diag+0x3b0/0x768 [kvm] [<000003ff80425af4>] kvm_handle_sie_intercept+0x1cc/0xcd0 [kvm] [<000003ff80422bb0>] __vcpu_run+0x7b8/0xfd0 [kvm] [<000003ff80423de6>] kvm_arch_vcpu_ioctl_run+0xee/0x3e0 [kvm] [<000003ff8040ccd8>] kvm_vcpu_ioctl+0x2c8/0x8d0 [kvm] [<00000001504ced06>] ksys_ioctl+0xae/0xe8 [<00000001504cedaa>] __s390x_sys_ioctl+0x2a/0x38 [<0000000150cb9034>] system_call+0xd8/0x2d8 2 locks held by CPU 2/KVM/16167: #0: 00000001951980c0 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x90/0x8d0 [kvm] #1: 000000019599c0f0 (&kvm->srcu){....}, at: __vcpu_run+0x4bc/0xfd0 [kvm] Last Breaking-Event-Address: [<000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm] irq event stamp: 11967 hardirqs last enabled at (11975): [<00000001502992f2>] console_unlock+0x4ca/0x650 hardirqs last disabled at (11982): [<0000000150298ee8>] console_unlock+0xc0/0x650 softirqs last enabled at (7940): [<0000000150cba6ca>] __do_softirq+0x422/0x4d8 softirqs last disabled at (7929): [<00000001501cd688>] do_softirq_own_stack+0x70/0x80 Considering what's being done here, let's fix this by removing the mutex assertion rather than acquiring the mutex for every other vcpu. Fixes: 201ae986ead7 ("KVM: s390: protvirt: Implement interrupt injection") Signed-off-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/20200415190353.63625-1-farman@linux.ibm.com Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-04-19Linux 5.7-rc2v5.7-rc2Linus Torvalds
2020-04-19mm: Fix MREMAP_DONTUNMAP accounting on VMA mergeBrian Geffon
When remapping a mapping where a portion of a VMA is remapped into another portion of the VMA it can cause the VMA to become split. During the copy_vma operation the VMA can actually be remerged if it's an anonymous VMA whose pages have not yet been faulted. This isn't normally a problem because at the end of the remap the original portion is unmapped causing it to become split again. However, MREMAP_DONTUNMAP leaves that original portion in place which means that the VMA which was split and then remerged is not actually split at the end of the mremap. This patch fixes a bug where we don't detect that the VMAs got remerged and we end up putting back VM_ACCOUNT on the next mapping which is completely unreleated. When that next mapping is unmapped it results in incorrectly unaccounting for the memory which was never accounted, and eventually we will underflow on the memory comittment. There is also another issue which is similar, we're currently accouting for the number of pages in the new_vma but that's wrong. We need to account for the length of the remap operation as that's all that is being added. If there was a mapping already at that location its comittment would have been adjusted as part of the munmap at the start of the mremap. A really simple repro can be seen in: https://gist.github.com/bgaff/e101ce99da7d9a8c60acc641d07f312c Fixes: e346b3813067 ("mm/mremap: add MREMAP_DONTUNMAP to mremap()") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Brian Geffon <bgeffon@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-19Merge tag 'clk-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux Pull clk fixes from Stephen Boyd: "Two build fixes for a couple clk drivers and a fix for the Unisoc serial clk where we want to keep it on for earlycon" * tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: clk: sprd: don't gate uart console clock clk: mmp2: fix link error without mmp2 clk: asm9260: fix __clk_hw_register_fixed_rate_with_accuracy typo
2020-04-19Merge tag 'x86-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 and objtool fixes from Thomas Gleixner: "A set of fixes for x86 and objtool: objtool: - Ignore the double UD2 which is emitted in BUG() when CONFIG_UBSAN_TRAP is enabled. - Support clang non-section symbols in objtool ORC dump - Fix switch table detection in .text.unlikely - Make the BP scratch register warning more robust. x86: - Increase microcode maximum patch size for AMD to cope with new CPUs which have a larger patch size. - Fix a crash in the resource control filesystem when the removal of the default resource group is attempted. - Preserve Code and Data Prioritization enabled state accross CPU hotplug. - Update split lock cpu matching to use the new X86_MATCH macros. - Change the split lock enumeration as Intel finaly decided that the IA32_CORE_CAPABILITIES bits are not architectural contrary to what the SDM claims. !@#%$^! - Add Tremont CPU models to the split lock detection cpu match. - Add a missing static attribute to make sparse happy" * tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/split_lock: Add Tremont family CPU models x86/split_lock: Bits in IA32_CORE_CAPABILITIES are not architectural x86/resctrl: Preserve CDP enable over CPU hotplug x86/resctrl: Fix invalid attempt at removing the default resource group x86/split_lock: Update to use X86_MATCH_INTEL_FAM6_MODEL() x86/umip: Make umip_insns static x86/microcode/AMD: Increase microcode PATCH_MAX_SIZE objtool: Make BP scratch register warning more robust objtool: Fix switch table detection in .text.unlikely objtool: Support Clang non-section symbols in ORC generation objtool: Support Clang non-section symbols in ORC dump objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings
2020-04-19Merge tag 'timers-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull time namespace fix from Thomas Gleixner: "An update for the proc interface of time namespaces: Use symbolic names instead of clockid numbers. The usability nuisance of numbers was noticed by Michael when polishing the man page" * tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
2020-04-19Merge tag 'perf-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf tooling fixes and updates from Thomas Gleixner: - Fix the header line of perf stat output for '--metric-only --per-socket' - Fix the python build with clang - The usual tools UAPI header synchronization * tag 'perf-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tools headers: Synchronize linux/bits.h with the kernel sources tools headers: Adopt verbatim copy of compiletime_assert() from kernel sources tools headers: Update x86's syscall_64.tbl with the kernel sources tools headers UAPI: Sync drm/i915_drm.h with the kernel sources tools headers UAPI: Update tools's copy of drm.h headers tools headers kvm: Sync linux/kvm.h with the kernel sources tools headers UAPI: Sync linux/fscrypt.h with the kernel sources tools include UAPI: Sync linux/vhost.h with the kernel sources tools arch x86: Sync asm/cpufeatures.h with the kernel sources tools headers UAPI: Sync linux/mman.h with the kernel tools headers UAPI: Sync sched.h with the kernel tools headers: Update linux/vdso.h and grab a copy of vdso/const.h perf stat: Fix no metric header if --per-socket and --metric-only set perf python: Check if clang supports -fno-semantic-interposition tools arch x86: Sync the msr-index.h copy with the kernel sources
2020-04-19Merge tag 'irq-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "A set of fixes/updates for the interrupt subsystem: - Remove setup_irq() and remove_irq(). All users have been converted so remove them before new users surface. - A set of bugfixes for various interrupt chip drivers - Add a few missing static attributes to address sparse warnings" * tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/irq-bcm7038-l1: Make bcm7038_l1_of_init() static irqchip/irq-mvebu-icu: Make legacy_bindings static irqchip/meson-gpio: Fix HARDIRQ-safe -> HARDIRQ-unsafe lock order irqchip/sifive-plic: Fix maximum priority threshold value irqchip/ti-sci-inta: Fix processing of masked irqs irqchip/mbigen: Free msi_desc on device teardown irqchip/gic-v4.1: Update effective affinity of virtual SGIs irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling genirq: Remove setup_irq() and remove_irq()
2020-04-19Merge tag 'sched-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "Two fixes for the scheduler: - Work around an uninitialized variable warning where GCC can't figure it out. - Allow 'isolcpus=' to skip unknown subparameters so that older kernels work with the commandline of a newer kernel. Improve the error output while at it" * tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/vtime: Work around an unitialized variable warning sched/isolation: Allow "isolcpus=" to skip unknown sub-parameters
2020-04-19Merge tag 'core-urgent-2020-04-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU fix from Thomas Gleixner: "A single bugfix for RCU to prevent taking a lock in NMI context" * tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common()
2020-04-19Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "Miscellaneous bug fixes and cleanups for ext4, including a fix for generic/388 in data=journal mode, removing some BUG_ON's, and cleaning up some compiler warnings" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: convert BUG_ON's to WARN_ON's in mballoc.c ext4: increase wait time needed before reuse of deleted inode numbers ext4: remove set but not used variable 'es' in ext4_jbd2.c ext4: remove set but not used variable 'es' ext4: do not zeroout extents beyond i_disksize ext4: fix return-value types in several function comments ext4: use non-movable memory for superblock readahead ext4: use matching invalidatepage in ext4_writepage
2020-04-19Merge tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs fixes from Steve French: "Three small smb3 fixes: two debug related (helping network tracing for SMB2 mounts, and the other removing an unintended debug line on signing failures), and one fixing a performance problem with 64K pages" * tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: smb3: remove overly noisy debug line in signing errors cifs: improve read performance for page size 64KB & cache=strict & vers=2.1+ cifs: dump the session id and keys also for SMB2 sessions
2020-04-19Merge tag 'flexible-array-member-5.7-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux Pull flexible-array member conversion from Gustavo Silva: "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] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member convertions) will also help to get completely rid of those sorts of issues. Notice that all of these patches have been baking in linux-next for quite a while now and, 238 more of these patches have already been merged into 5.7-rc1. There are a couple hundred more of these issues waiting to be addressed in the whole codebase" [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") * tag 'flexible-array-member-5.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (28 commits) xattr.h: Replace zero-length array with flexible-array member uapi: linux: fiemap.h: Replace zero-length array with flexible-array member uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member tpm_eventlog.h: Replace zero-length array with flexible-array member ti_wilink_st.h: Replace zero-length array with flexible-array member swap.h: Replace zero-length array with flexible-array member skbuff.h: Replace zero-length array with flexible-array member sched: topology.h: Replace zero-length array with flexible-array member rslib.h: Replace zero-length array with flexible-array member rio.h: Replace zero-length array with flexible-array member posix_acl.h: Replace zero-length array with flexible-array member platform_data: wilco-ec.h: Replace zero-length array with flexible-array member memcontrol.h: Replace zero-length array with flexible-array member list_lru.h: Replace zero-length array with flexible-array member lib: cpu_rmap: Replace zero-length array with flexible-array member irq.h: Replace zero-length array with flexible-array member ihex.h: Replace zero-length array with flexible-array member igmp.h: Replace zero-length array with flexible-array member genalloc.h: Replace zero-length array with flexible-array member ethtool.h: Replace zero-length array with flexible-array member ...
2020-04-18Merge tag 'scsi-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI fixes from James Bottomley: "Seven fixes: three in target, one on a sg error leg, two in qla2xxx fixing warnings introduced in the last merge window and updating MAINTAINERS and one in hisi_sas fixing a problem introduced by libata" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: sg: add sg_remove_request in sg_common_write scsi: target: tcmu: reset_ring should reset TCMU_DEV_BIT_BROKEN scsi: target: fix PR IN / READ FULL STATUS for FC scsi: target: Write NULL to *port_nexus_ptr if no ISID scsi: MAINTAINERS: Update qla2xxx FC-SCSI driver maintainer scsi: qla2xxx: Fix regression warnings scsi: hisi_sas: Fix build error without SATA_HOST
2020-04-18xattr.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18uapi: linux: fiemap.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18uapi: linux: dlm_device.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18tpm_eventlog.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18ti_wilink_st.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18swap.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18skbuff.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18sched: topology.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18rslib.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18rio.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18posix_acl.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18platform_data: wilco-ec.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18memcontrol.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18list_lru.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18lib: cpu_rmap: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18irq.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18ihex.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18igmp.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18genalloc.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-04-18ethtool.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>