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2021-06-29mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMAMike Rapoport2-2/+2
After removal of DISCINTIGMEM the NEED_MULTIPLE_NODES and NUMA configuration options are equivalent. Drop CONFIG_NEED_MULTIPLE_NODES and use CONFIG_NUMA instead. Done with $ sed -i 's/CONFIG_NEED_MULTIPLE_NODES/CONFIG_NUMA/' \ $(git grep -wl CONFIG_NEED_MULTIPLE_NODES) $ sed -i 's/NEED_MULTIPLE_NODES/NUMA/' \ $(git grep -wl NEED_MULTIPLE_NODES) with manual tweaks afterwards. [rppt@linux.ibm.com: fix arm boot crash] Link: https://lkml.kernel.org/r/YMj9vHhHOiCVN4BF@linux.ibm.com Link: https://lkml.kernel.org/r/20210608091316.3622-9-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: David Hildenbrand <david@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matt Turner <mattst88@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-28Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds4-223/+43
Pull kvm updates from Paolo Bonzini: "This covers all architectures (except MIPS) so I don't expect any other feature pull requests this merge window. ARM: - Add MTE support in guests, complete with tag save/restore interface - Reduce the impact of CMOs by moving them in the page-table code - Allow device block mappings at stage-2 - Reduce the footprint of the vmemmap in protected mode - Support the vGIC on dumb systems such as the Apple M1 - Add selftest infrastructure to support multiple configuration and apply that to PMU/non-PMU setups - Add selftests for the debug architecture - The usual crop of PMU fixes PPC: - Support for the H_RPT_INVALIDATE hypercall - Conversion of Book3S entry/exit to C - Bug fixes S390: - new HW facilities for guests - make inline assembly more robust with KASAN and co x86: - Allow userspace to handle emulation errors (unknown instructions) - Lazy allocation of the rmap (host physical -> guest physical address) - Support for virtualizing TSC scaling on VMX machines - Optimizations to avoid shattering huge pages at the beginning of live migration - Support for initializing the PDPTRs without loading them from memory - Many TLB flushing cleanups - Refuse to load if two-stage paging is available but NX is not (this has been a requirement in practice for over a year) - A large series that separates the MMU mode (WP/SMAP/SMEP etc.) from CR0/CR4/EFER, using the MMU mode everywhere once it is computed from the CPU registers - Use PM notifier to notify the guest about host suspend or hibernate - Support for passing arguments to Hyper-V hypercalls using XMM registers - Support for Hyper-V TLB flush hypercalls and enlightened MSR bitmap on AMD processors - Hide Hyper-V hypercalls that are not included in the guest CPUID - Fixes for live migration of virtual machines that use the Hyper-V "enlightened VMCS" optimization of nested virtualization - Bugfixes (not many) Generic: - Support for retrieving statistics without debugfs - Cleanups for the KVM selftests API" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (314 commits) KVM: x86: rename apic_access_page_done to apic_access_memslot_enabled kvm: x86: disable the narrow guest module parameter on unload selftests: kvm: Allows userspace to handle emulation errors. kvm: x86: Allow userspace to handle emulation errors KVM: x86/mmu: Let guest use GBPAGES if supported in hardware and TDP is on KVM: x86/mmu: Get CR4.SMEP from MMU, not vCPU, in shadow page fault KVM: x86/mmu: Get CR0.WP from MMU, not vCPU, in shadow page fault KVM: x86/mmu: Drop redundant rsvd bits reset for nested NPT KVM: x86/mmu: Optimize and clean up so called "last nonleaf level" logic KVM: x86: Enhance comments for MMU roles and nested transition trickiness KVM: x86/mmu: WARN on any reserved SPTE value when making a valid SPTE KVM: x86/mmu: Add helpers to do full reserved SPTE checks w/ generic MMU KVM: x86/mmu: Use MMU's role to determine PTTYPE KVM: x86/mmu: Collapse 32-bit PAE and 64-bit statements for helpers KVM: x86/mmu: Add a helper to calculate root from role_regs KVM: x86/mmu: Add helper to update paging metadata KVM: x86/mmu: Don't update nested guest's paging bitmasks if CR0.PG=0 KVM: x86/mmu: Consolidate reset_rsvds_bits_mask() calls KVM: x86/mmu: Use MMU role_regs to get LA57, and drop vCPU LA57 helper KVM: x86/mmu: Get nested MMU's root level from the MMU's role ...
2021-06-28Merge tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-3/+2
Pull scheduler udpates from Ingo Molnar: - Changes to core scheduling facilities: - Add "Core Scheduling" via CONFIG_SCHED_CORE=y, which enables coordinated scheduling across SMT siblings. This is a much requested feature for cloud computing platforms, to allow the flexible utilization of SMT siblings, without exposing untrusted domains to information leaks & side channels, plus to ensure more deterministic computing performance on SMT systems used by heterogenous workloads. There are new prctls to set core scheduling groups, which allows more flexible management of workloads that can share siblings. - Fix task->state access anti-patterns that may result in missed wakeups and rename it to ->__state in the process to catch new abuses. - Load-balancing changes: - Tweak newidle_balance for fair-sched, to improve 'memcache'-like workloads. - "Age" (decay) average idle time, to better track & improve workloads such as 'tbench'. - Fix & improve energy-aware (EAS) balancing logic & metrics. - Fix & improve the uclamp metrics. - Fix task migration (taskset) corner case on !CONFIG_CPUSET. - Fix RT and deadline utilization tracking across policy changes - Introduce a "burstable" CFS controller via cgroups, which allows bursty CPU-bound workloads to borrow a bit against their future quota to improve overall latencies & batching. Can be tweaked via /sys/fs/cgroup/cpu/<X>/cpu.cfs_burst_us. - Rework assymetric topology/capacity detection & handling. - Scheduler statistics & tooling: - Disable delayacct by default, but add a sysctl to enable it at runtime if tooling needs it. Use static keys and other optimizations to make it more palatable. - Use sched_clock() in delayacct, instead of ktime_get_ns(). - Misc cleanups and fixes. * tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits) sched/doc: Update the CPU capacity asymmetry bits sched/topology: Rework CPU capacity asymmetry detection sched/core: Introduce SD_ASYM_CPUCAPACITY_FULL sched_domain flag psi: Fix race between psi_trigger_create/destroy sched/fair: Introduce the burstable CFS controller sched/uclamp: Fix uclamp_tg_restrict() sched/rt: Fix Deadline utilization tracking during policy change sched/rt: Fix RT utilization tracking during policy change sched: Change task_struct::state sched,arch: Remove unused TASK_STATE offsets sched,timer: Use __set_current_state() sched: Add get_current_state() sched,perf,kvm: Fix preemption condition sched: Introduce task_is_running() sched: Unbreak wakeups sched/fair: Age the average idle time sched/cpufreq: Consider reduced CPU capacity in energy calculation sched/fair: Take thermal pressure into account while estimating energy thermal/cpufreq_cooling: Update offline CPUs per-cpu thermal_pressure sched/fair: Return early from update_tg_cfs_load() if delta == 0 ...
2021-06-28Merge tag 'perf-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-17/+0
Pull perf events updates from Ingo Molnar: - Platform PMU driver updates: - x86 Intel uncore driver updates for Skylake (SNR) and Icelake (ICX) servers - Fix RDPMC support - Fix [extended-]PEBS-via-PT support - Fix Sapphire Rapids event constraints - Fix :ppp support on Sapphire Rapids - Fix fixed counter sanity check on Alder Lake & X86_FEATURE_HYBRID_CPU - Other heterogenous-PMU fixes - Kprobes: - Remove the unused and misguided kprobe::fault_handler callbacks. - Warn about kprobes taking a page fault. - Fix the 'nmissed' stat counter. - Misc cleanups and fixes. * tag 'perf-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Fix task context PMU for Hetero perf/x86/intel: Fix instructions:ppp support in Sapphire Rapids perf/x86/intel: Add more events requires FRONTEND MSR on Sapphire Rapids perf/x86/intel: Fix fixed counter check warning for some Alder Lake perf/x86/intel: Fix PEBS-via-PT reload base value for Extended PEBS perf/x86: Reset the dirty counter to prevent the leak for an RDPMC task kprobes: Do not increment probe miss count in the fault handler x86,kprobes: WARN if kprobes tries to handle a fault kprobes: Remove kprobe::fault_handler uprobes: Update uprobe_write_opcode() kernel-doc comment perf/hw_breakpoint: Fix DocBook warnings in perf hw_breakpoint perf/core: Fix DocBook warnings perf/core: Make local function perf_pmu_snapshot_aux() static perf/x86/intel/uncore: Enable I/O stacks to IIO PMON mapping on ICX perf/x86/intel/uncore: Enable I/O stacks to IIO PMON mapping on SNR perf/x86/intel/uncore: Generalize I/O stacks to PMON mapping procedure perf/x86/intel/uncore: Drop unnecessary NULL checks after container_of()
2021-06-26powerpc/interrupt: Use names in check_return_regs_valid()Christophe Leroy1-2/+2
trap->regs == 0x3000 is trap_is_scv() trap 0x500 is INTERRUPT_EXTERNAL Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/d48bf0184a1de185eb0ed3282247f8a294710674.1624632537.git.christophe.leroy@csgroup.eu
2021-06-26powerpc/interrupt: Also use exit_must_hard_disable() on PPC32Christophe Leroy1-5/+3
Reduce #ifdefs a bit by making exit_must_hard_disable() return true on PPC32. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/52531029563c1fc823b790058e799d0ca71b028c.1624631463.git.christophe.leroy@csgroup.eu
2021-06-25Merge tag 'kvmarm-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEADPaolo Bonzini2-3/+3
KVM/arm64 updates for v5.14. - Add MTE support in guests, complete with tag save/restore interface - Reduce the impact of CMOs by moving them in the page-table code - Allow device block mappings at stage-2 - Reduce the footprint of the vmemmap in protected mode - Support the vGIC on dumb systems such as the Apple M1 - Add selftest infrastructure to support multiple configuration and apply that to PMU/non-PMU setups - Add selftests for the debug architecture - The usual crop of PMU fixes
2021-06-26powerpc/sysfs: Replace sizeof(arr)/sizeof(arr[0]) with ARRAY_SIZEJason Wang1-6/+6
The ARRAY_SIZE macro is more compact and more formal in linux source. Signed-off-by: Jason Wang <wangborong@cdjrlc.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210624063632.25632-1-wangborong@cdjrlc.com
2021-06-26powerpc/stacktrace: Fix spurious "stale" traces in raise_backtrace_ipi()Michael Ellerman1-6/+20
In raise_backtrace_ipi() we iterate through the cpumask of CPUs, sending each an IPI asking them to do a backtrace, but we don't wait for the backtrace to happen. We then iterate through the CPU mask again, and if any CPU hasn't done the backtrace and cleared itself from the mask, we print a trace on its behalf, noting that the trace may be "stale". This works well enough when a CPU is not responding, because in that case it doesn't receive the IPI and the sending CPU is left to print the trace. But when all CPUs are responding we are left with a race between the sending and receiving CPUs, if the sending CPU wins the race then it will erroneously print a trace. This leads to spurious "stale" traces from the sending CPU, which can then be interleaved messily with the receiving CPU, note the CPU numbers, eg: [ 1658.929157][ C7] rcu: Stack dump where RCU GP kthread last ran: [ 1658.929223][ C7] Sending NMI from CPU 7 to CPUs 1: [ 1658.929303][ C1] NMI backtrace for cpu 1 [ 1658.929303][ C7] CPU 1 didn't respond to backtrace IPI, inspecting paca. [ 1658.929362][ C1] CPU: 1 PID: 325 Comm: kworker/1:1H Tainted: G W E 5.13.0-rc2+ #46 [ 1658.929405][ C7] irq_soft_mask: 0x01 in_mce: 0 in_nmi: 0 current: 325 (kworker/1:1H) [ 1658.929465][ C1] Workqueue: events_highpri test_work_fn [test_lockup] [ 1658.929549][ C7] Back trace of paca->saved_r1 (0xc0000000057fb400) (possibly stale): [ 1658.929592][ C1] NIP: c00000000002cf50 LR: c008000000820178 CTR: c00000000002cfa0 To fix it, change the logic so that the sending CPU waits 5s for the receiving CPU to print its trace. If the receiving CPU prints its trace successfully then the sending CPU just continues, avoiding any spurious "stale" trace. This has the added benefit of allowing all CPUs to print their traces in order and avoids any interleaving of their output. Fixes: 5cc05910f26e ("powerpc/64s: Wire up arch_trigger_cpumask_backtrace()") Cc: stable@vger.kernel.org # v4.18+ Reported-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210625140408.3351173-1-mpe@ellerman.id.au
2021-06-25powerpc/rtas-rtc: remove unused constantNathan Lynch1-1/+1
RTAS_CLOCK_BUSY is unused, remove it. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210503175811.1528208-1-nathanl@linux.ibm.com
2021-06-25powerpc: Fix is_kvm_guest() / kvm_para_available()Michael Ellerman1-4/+6
Commit a21d1becaa3f ("powerpc: Reintroduce is_kvm_guest() as a fast-path check") added is_kvm_guest() and changed kvm_para_available() to use it. is_kvm_guest() checks a static key, kvm_guest, and that static key is set in check_kvm_guest(). The problem is check_kvm_guest() is only called on pseries, and even then only in some configurations. That means is_kvm_guest() always returns false on all non-pseries and some pseries depending on configuration. That's a bug. For PR KVM guests this is noticable because they no longer do live patching of themselves, which can be detected by the omission of a message in dmesg such as: KVM: Live patching for a fast VM worked To fix it make check_kvm_guest() an initcall, to ensure it's always called at boot. It needs to be core so that it runs before kvm_guest_init() which is postcore. To be an initcall it needs to return int, where 0 means success, so update that. We still call it manually in pSeries_smp_probe(), because that runs before init calls are run. Fixes: a21d1becaa3f ("powerpc: Reintroduce is_kvm_guest() as a fast-path check") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210623130514.2543232-1-mpe@ellerman.id.au
2021-06-25powerpc/64s: Make prom_init require RELOCATABLEMichael Ellerman1-56/+2
When we boot from open firmware (OF) using PPC_OF_BOOT_TRAMPOLINE, aka. prom_init, we run parts of the kernel at an address other than the link address. That happens because OF loads the kernel above zero (OF is at zero) and we run prom_init before copying the kernel down to zero. Currently that works even for non-relocatable kernels, because we do various fixups to the prom_init code to make it run where it's loaded. However those fixups are not sufficient if the kernel becomes large enough. In that case prom_init()'s final call to __start() can end up generating a plt branch: bl c000000002000018 <00000078.plt_branch.__start> That results in the kernel jumping to the linked address of __start, 0xc000000000000000, when really it needs to jump to the 0xc000000000000000 + the runtime address because the kernel is still running at the load address. We could do further shenanigans to handle that, see Jordan's patch for example: https://lore.kernel.org/linuxppc-dev/20210421021721.1539289-1-jniethe5@gmail.com However it is much simpler to just require a kernel with prom_init() to be built relocatable. The result works in all configurations without further work, and requires less code. This should have no effect on most people, as our defconfigs and essentially all distro configs already have RELOCATABLE enabled. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210623130454.2542945-1-mpe@ellerman.id.au
2021-06-25powerpc/kprobes: Warn if instruction patching failedNaveen N. Rao1-2/+2
When arming and disarming probes, we currently assume that instruction patching can never fail, and don't have a mechanism to surface errors. Add a warning in case instruction patching ever fails. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/18d7b1309f938c08ce07738100932b551bdd3a52.1621416666.git.naveen.n.rao@linux.vnet.ibm.com
2021-06-25powerpc/kprobes: Roll IS_RFI() macro into IS_RFID()Naveen N. Rao1-2/+2
In kprobes and xmon, we should exclude both 32-bit and 64-bit variants of mtmsr and rfi instructions from being stepped. Have IS_RFID() also detect a rfi instruction similar to IS_MTMSRD(). Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/eee32e1b75dae85d471c89b4c0a123ad4b0aabf8.1621416666.git.naveen.n.rao@linux.vnet.ibm.com
2021-06-25powerpc/kprobes: Fix Oops by passing ppc_inst as a pointer to emulate_step() on ppc32Naveen N. Rao1-2/+6
Trying to use a kprobe on ppc32 results in the below splat: BUG: Unable to handle kernel data access on read at 0x7c0802a6 Faulting instruction address: 0xc002e9f0 Oops: Kernel access of bad area, sig: 11 [#1] BE PAGE_SIZE=4K PowerPC 44x Platform Modules linked in: CPU: 0 PID: 89 Comm: sh Not tainted 5.13.0-rc1-01824-g3a81c0495fdb #7 NIP: c002e9f0 LR: c0011858 CTR: 00008a47 REGS: c292fd50 TRAP: 0300 Not tainted (5.13.0-rc1-01824-g3a81c0495fdb) MSR: 00009000 <EE,ME> CR: 24002002 XER: 20000000 DEAR: 7c0802a6 ESR: 00000000 <snip> NIP [c002e9f0] emulate_step+0x28/0x324 LR [c0011858] optinsn_slot+0x128/0x10000 Call Trace: opt_pre_handler+0x7c/0xb4 (unreliable) optinsn_slot+0x128/0x10000 ret_from_syscall+0x0/0x28 The offending instruction is: 81 24 00 00 lwz r9,0(r4) Here, we are trying to load the second argument to emulate_step(): struct ppc_inst, which is the instruction to be emulated. On ppc64, structures are passed in registers when passed by value. However, per the ppc32 ABI, structures are always passed to functions as pointers. This isn't being adhered to when setting up the call to emulate_step() in the optprobe trampoline. Fix the same. Fixes: eacf4c0202654a ("powerpc: Enable OPTPROBES on PPC32") Cc: stable@vger.kernel.org Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/5bdc8cbc9a95d0779e27c9ddbf42b40f51f883c0.1624425798.git.christophe.leroy@csgroup.eu
2021-06-25powerpc/64s: Fix copy-paste data exposure into newly created tasksNicholas Piggin1-16/+32
copy-paste contains implicit "copy buffer" state that can contain arbitrary user data (if the user process executes a copy instruction). This could be snooped by another process if a context switch hits while the state is live. So cp_abort is executed on context switch to clear out possible sensitive data and prevent the leak. cp_abort is done after the low level _switch(), which means it is never reached by newly created tasks, so they could snoop on this buffer between their first and second context switch. Fix this by doing the cp_abort before calling _switch. Add some comments which should make the issue harder to miss. Fixes: 07d2a628bc000 ("powerpc/64s: Avoid cpabort in context switch when possible") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210622053036.474678-1-npiggin@gmail.com
2021-06-25powerpc/32: Avoid #ifdef nested with FTR_SECTION on booke syscall entryChristophe Leroy1-2/+2
On booke, SYSCALL_ENTRY macro nests an FTR_SECTION with a #ifdef CONFIG_KVM_BOOKE_HV. Duplicate the single instruction alternative to avoid nesting. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/33db61d5f85146262dbe26648f8f87eca3cae393.1622818435.git.christophe.leroy@csgroup.eu
2021-06-25powerpc/32: Reduce code duplication of system call entryChristophe Leroy3-37/+19
booke and non booke do pretty similar things in SYSCALL_ENTRY macro just before calling jumping to transfer_to_syscall(). Do them in transfer_to_syscall() instead. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/552e27fa09394a6bc70585fcdfa237f99a5d1267.1622818435.git.christophe.leroy@csgroup.eu
2021-06-25powerpc/32: Interchange r1 and r11 in SYSCALL_ENTRY on bookeChristophe Leroy2-10/+11
To better match non booke version of SYSCALL_ENTRY macro, interchange r1 and r11 in the booke version. While at it, in both versions use r1 instead of r11 to save _NIP and _CCR. All other uses of r11 will go away in next patch, so don't bother changing them for now. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1684c39724a069b0ce1aa82eaee6ec194e354e4e.1622818435.git.christophe.leroy@csgroup.eu
2021-06-25powerpc/32: Interchange r10 and r12 in SYSCALL_ENTRY on non bookeChristophe Leroy1-17/+17
To better match booke version of SYSCALL_ENTRY macro, interchange r10 and r12 in the non booke version. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/5ab3a517bc883a2fc905fb2cb5ee9344f37b2cfa.1622818435.git.christophe.leroy@csgroup.eu
2021-06-25powerpc: Remove klimitChristophe Leroy3-8/+4
klimit is a global variable initialised at build time with the value of _end. This variable is never modified, so _end symbol can be used directly. Remove klimit. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/9fa9ba6807c17f93f35a582c199c646c4a8bfd9c.1622800638.git.christophe.leroy@csgroup.eu
2021-06-25powerpc: Offline CPU in stop_this_cpu()Nicholas Piggin1-0/+11
printk_safe_flush_on_panic() has special lock breaking code for the case where we panic()ed with the console lock held. It relies on panic IPI causing other CPUs to mark themselves offline. Do as most other architectures do. This effectively reverts commit de6e5d38417e ("powerpc: smp_send_stop do not offline stopped CPUs"), unfortunately it may result in some false positive warnings, but the alternative is more situations where we can crash without getting messages out. Fixes: de6e5d38417e ("powerpc: smp_send_stop do not offline stopped CPUs") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210623041245.865134-1-npiggin@gmail.com
2021-06-25powerpc/64s: Remove irq mask workaround in accumulate_stolen_time()Nicholas Piggin1-11/+0
The caller has been moved to C after irq soft-mask state has been reconciled, and Linux IRQs have been marked as disabled, so this no longer needs to play games with IRQ internals. Fixes: 68b34588e202 ("powerpc/64/sycall: Implement syscall entry/exit logic in C") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210623022924.704645-1-npiggin@gmail.com
2021-06-25powerpc/pseries: Enable hardlockup watchdog for PowerVM partitionsNicholas Piggin1-4/+9
PowerVM will not arbitrarily oversubscribe or stop guests, page out the guest kernel text to a NFS volume connected by carrier pigeon to abacus based storage, etc., as a KVM host might. So PowerVM guests are not likely to be killed by the hard lockup watchdog in normal operation, even with shared processor LPARs which still get a minimum allotment of CPU time. Enable the hard lockup detector by default on !KVM guests, which we will assume is PowerVM. It has been useful in finding problems on bare metal kernels. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210623021528.702241-1-npiggin@gmail.com
2021-06-25powerpc/64s/interrupt: Check and fix srr_valid without crashingNicholas Piggin1-0/+89
The PPC_RFI_SRR_DEBUG check added by patch "powerpc/64s: avoid reloading (H)SRR registers if they are still valid" has a few deficiencies. It does not fix the actual problem, it's not enabled by default, and it causes a program check interrupt which can cause more difficulties. However there are a lot of paths which may clobber SRRs or change return regs, and difficult to have a high confidence that all paths are covered without wider testing. Add a relatively low overhead always-enabled check that catches most such cases, reports once, and fixes it so the kernel can continue. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Rebase, use switch & INT names, squash in race fix from Nick] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2021-06-25powerpc/interrupt: Remove prep_irq_for_user_exit()Christophe Leroy1-13/+3
prep_irq_for_user_exit() has only one caller, squash it inside that caller. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-18-npiggin@gmail.com
2021-06-25powerpc/interrupt: Refactor prep_irq_for_{user/kernel_enabled}_exit()Christophe Leroy1-22/+7
prep_irq_for_user_exit() is a superset of prep_irq_for_kernel_enabled_exit(). Rename prep_irq_for_kernel_enabled_exit() as prep_irq_for_enabled_exit() and have prep_irq_for_user_exit() use it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-17-npiggin@gmail.com
2021-06-25powerpc/interrupt: Interchange prep_irq_for_{kernel_enabled/user}_exit()Christophe Leroy1-12/+11
prep_irq_for_user_exit() is a superset of prep_irq_for_kernel_enabled_exit(). In order to allow refactoring in following patch, interchange the two. This will allow prep_irq_for_user_exit() to call a renamed version of prep_irq_for_kernel_enabled_exit(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-16-npiggin@gmail.com
2021-06-25powerpc/interrupt: Refactor interrupt_exit_user_prepare()Christophe Leroy1-54/+3
interrupt_exit_user_prepare() is a superset of interrupt_exit_user_prepare_main(). Refactor to avoid code duplication. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-15-npiggin@gmail.com
2021-06-25powerpc/interrupt: Rename and lightly change syscall_exit_prepare_main()Christophe Leroy1-5/+4
Rename syscall_exit_prepare_main() into interrupt_exit_prepare_main() Pass it the 'ret' so that it can 'or' it directly instead of oring twice, once inside the function and once outside. And remove 'r3' parameter which is not used. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [np: split out some changes into other patches] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-14-npiggin@gmail.com
2021-06-25powerpc/64: use interrupt restart table to speed up return from interruptNicholas Piggin3-152/+387
Use the restart table facility to return from interrupt or system calls without disabling MSR[EE] or MSR[RI]. Interrupt return asm is put into the low soft-masked region, to prevent interrupts being processed here, although they are still taken as masked interrupts which causes SRRs to be clobbered, and a pending soft-masked interrupt to require replaying. The return code uses restart table regions to redirct to a fixup handler rather than continue with the exit, if such an interrupt happens. In this case the interrupt return is redirected to a fixup handler which reloads r1 for the interrupt stack and reloads registers and sets state up to replay the soft-masked interrupt and try the exit again. Some types of security exit fallback flushes and barriers are currently unable to cope with reentrant interrupts, e.g., because they store some state in the scratch SPR which would be clobbered even by masked interrupts. For now the interrupts-enabled exits are disabled when these flushes are used. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Guard unused exit_must_hard_disable() as reported by lkp] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-13-npiggin@gmail.com
2021-06-25powerpc/64: treat low kernel text as irqs soft-maskedNicholas Piggin3-10/+27
Treat code below __end_soft_masked as soft-masked for the purpose of alternate return. 64s already mostly does this for scv entry. This will be used to exit from interrupts without disabling MSR[EE]. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-12-npiggin@gmail.com
2021-06-25powerpc/64: interrupt soft-enable race fixNicholas Piggin1-0/+95
Prevent interrupt restore from allowing racing hard interrupts going ahead of previous soft-pending ones, by using the soft-masked restart handler to allow a store to clear the soft-mask while knowing nothing is soft-pending. This probably doesn't matter much in practice, but it's a simple demonstrator / test case to exercise the restart table logic. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-11-npiggin@gmail.com
2021-06-25powerpc/64: allow alternate return locations for soft-masked interruptsNicholas Piggin3-2/+86
The exception table fixup adjusts a failed page fault's interrupt return location if it was taken at an address specified in the exception table, to a corresponding fixup handler address. Introduce a variation of that idea which adds a fixup table for NMIs and soft-masked asynchronous interrupts. This will be used to protect certain critical sections that are sensitive to being clobbered by interrupts coming in (due to using the same SPRs and/or irq soft-mask state). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-10-npiggin@gmail.com
2021-06-25powerpc/64s: save one more register in the masked interrupt handlerNicholas Piggin1-14/+20
This frees up one more register (and takes advantage of that to clean things up a little bit). This register will be used in the following patch. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-9-npiggin@gmail.com
2021-06-25powerpc/64s: system call avoid setting MSR[RI] until we set MSR[EE]Nicholas Piggin2-4/+2
This extends the MSR[RI]=0 window a little further into the system call in order to pair RI and EE enabling with a single mtmsrd. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-8-npiggin@gmail.com
2021-06-25powerpc/64: move interrupt return asm to interrupt_64.SNicholas Piggin3-624/+639
The next patch would like to move interrupt return assembly code to a low location before general text, so move it into its own file and include via head_64.S Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-7-npiggin@gmail.com
2021-06-25powerpc/64s: avoid reloading (H)SRR registers if they are still validNicholas Piggin23-134/+273
When an interrupt is taken, the SRR registers are set to return to where it left off. Unless they are modified in the meantime, or the return address or MSR are modified, there is no need to reload these registers when returning from interrupt. Introduce per-CPU flags that track the validity of SRR and HSRR registers. These are cleared when returning from interrupt, when using the registers for something else (e.g., OPAL calls), when adjusting the return address or MSR of a context, and when context switching (which changes the return address and MSR). This improves the performance of interrupt returns. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Fold in fixup patch from Nick] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-5-npiggin@gmail.com
2021-06-25powerpc/64s: introduce different functions to return from SRR vs HSRR interruptsNicholas Piggin4-55/+92
This makes no real difference yet except that HSRR type interrupts will use hrfid to return. This is important for the next patch. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-4-npiggin@gmail.com
2021-06-25powerpc: remove interrupt exit helpers unused argumentNicholas Piggin1-2/+2
The msr argument is not used, remove it. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-3-npiggin@gmail.com
2021-06-25powerpc/interrupt: Fix CONFIG ifdef typoChristophe Leroy1-1/+1
CONFIG_PPC_BOOK3S should be CONFIG_PPC_BOOK3S_64. restore_math is a no-op for other configurations. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [np: split from another patch] Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210617155116.2167984-2-npiggin@gmail.com
2021-06-25powerpc/prom_init: Pass linux_banner to firmware via option vector 7Michael Ellerman1-0/+13
Pass the value of linux_banner to firmware via option vector 7. Option vector 7 is described in "LoPAR" Linux on Power Architecture Reference v2.9, in table B.7 on page 824: An ASCII character formatted null terminated string that describes the client operating system. The string shall be human readable and may be displayed on the console. The string can be up to 256 bytes total, including the nul terminator. linux_banner contains lots of information, and should make it possible to identify the exact kernel version that is running: const char linux_banner[] = "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@" LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n"; For example: Linux version 4.15.0-144-generic (buildd@bos02-ppc64el-018) (gcc version 7.5.0 (Ubuntu 7.5.0-3ubuntu1~18.04)) #148-Ubuntu SMP Sat May 8 02:32:13 UTC 2021 (Ubuntu 4.15.0-144.148-generic 4.15.18) It's also printed at boot to the console/dmesg, which should make it possible to correlate what firmware receives with the console/dmesg on the machine. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210621064938.2021419-2-mpe@ellerman.id.au
2021-06-25powerpc/prom_init: Convert prom_strcpy() into prom_strscpy_pad()Michael Ellerman1-6/+24
In a subsequent patch we'd like to have something like a strscpy_pad() implementation usable in prom_init.c. Currently we have a strcpy() implementation with only one caller, so convert it into strscpy_pad() and update the caller. Reviewed-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210621064938.2021419-1-mpe@ellerman.id.au
2021-06-21powerpc/microwatt: Use standard 16550 UART for consoleBenjamin Herrenschmidt1-0/+39
This adds support to the Microwatt platform to use the standard 16550-style UART which available in the standalone Microwatt FPGA. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/YMwXGCTzedpQje7r@thinks.paulus.ozlabs.org
2021-06-21powerpc/kprobes: Mark newly allocated probes as ROXRussell Currey1-0/+17
Add the arch specific insn page allocator for powerpc. This allocates ROX pages if STRICT_KERNEL_RWX is enabled. These pages are only written to with patch_instruction() which is able to write RO pages. Signed-off-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [jpn: Reword commit message, switch to __vmalloc_node_range()] Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210609013431.9805-5-jniethe5@gmail.com
2021-06-21powerpc/modules: Make module_alloc() Strict Module RWX awareJordan Niethe1-1/+3
Make module_alloc() use PAGE_KERNEL protections instead of PAGE_KERNEL_EXEX if Strict Module RWX is enabled. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210609013431.9805-4-jniethe5@gmail.com
2021-06-21powerpc/security: Add a security feature for STF barrierNicholas Piggin1-5/+2
Rather than tying this mitigation to RFI L1D flush requirement, add a new bit for it. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210503130243.891868-3-npiggin@gmail.com
2021-06-21powerpc/powernv: Fix machine check reporting of async store errorsNicholas Piggin1-8/+40
POWER9 and POWER10 asynchronous machine checks due to stores have their cause reported in SRR1 but SRR1[42] is set, which in other cases indicates DSISR cause. Check for these cases and clear SRR1[42], so the cause matching uses the i-side (SRR1) table. Fixes: 7b9f71f974a1 ("powerpc/64s: POWER9 machine check handler") Fixes: 201220bb0e8c ("powerpc/powernv: Machine check handler for POWER10") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210517140355.2325406-1-npiggin@gmail.com
2021-06-19Merge tag 'powerpc-5.13-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds1-5/+4
Pull powerpc fixes from Michael Ellerman: "Fix initrd corruption caused by our recent change to use relative jump labels. Fix a crash using perf record on systems without a hardware PMU backend. Rework our 64-bit signal handling slighty to make it more closely match the old behaviour, after the recent change to use unsafe user accessors. Thanks to Anastasia Kovaleva, Athira Rajeev, Christophe Leroy, Daniel Axtens, Greg Kurz, and Roman Bolshakov" * tag 'powerpc-5.13-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/perf: Fix crash in perf_instruction_pointer() when ppmu is not set powerpc: Fix initrd corruption with relative jump labels powerpc/signal64: Copy siginfo before changing regs->nip powerpc/mem: Add back missing header to fix 'no previous prototype' error
2021-06-18sched: Introduce task_is_running()Peter Zijlstra1-2/+2
Replace a bunch of 'p->state == TASK_RUNNING' with a new helper: task_is_running(p). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210611082838.222401495@infradead.org
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