[PATCH v3 40/51] cpuidle,powerdomain: Remove trace_.*_rcuidle()

OMAP was the one and only user. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Ulf Hansson Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- arch/arm/mach-omap2/powerdomain.c | 10 +- drivers/base/power/runtime.c

[PATCH v3 34/51] trace: WARN on rcuidle

ARCH_WANTS_NO_INSTR (a superset of CONFIG_GENERIC_ENTRY) disallows any and all tracing when RCU isn't enabled. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- include/linux/tracepoint.h | 15

[PATCH v3 00/51] cpuidle,rcu: Clean up the mess

Hi All! The (hopefully) final respin of cpuidle vs rcu cleanup patches. Barring any objections I'll be queueing these patches in tip/sched/core in the next few days. v2: https://lkml.kernel.org/r/20220919095939.761690...@infradead.org These here patches clean up the mess that is cpuidle vs rcuid

[PATCH v3 41/51] cpuidle,clk: Remove trace_.*_rcuidle()

OMAP was the one and only user. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Ulf Hansson Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- drivers/clk/clk.c |8 1 file changed, 4 insertions(+), 4 deletions(-) --

[PATCH v3 35/51] trace,hardirq: No moar _rcuidle() tracing

Robot reported that trace_hardirqs_{on,off}() tickle the forbidden _rcuidle() tracepoint through local_irq_{en,dis}able(). For 'sane' configs, these calls will only happen with RCU enabled and as such can use the regular tracepoint. This also means it's possible to trace them from NMI context agai

[PATCH v3 50/51] cpuidle: Comments about noinstr/__cpuidle

Add a few words on noinstr / __cpuidle usage. Signed-off-by: Peter Zijlstra (Intel) --- drivers/cpuidle/cpuidle.c | 12 include/linux/compiler_types.h | 10 ++ 2 files changed, 22 insertions(+) --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -252

[PATCH v3 51/51] context_tracking: Fix noinstr vs KASAN

vmlinux.o: warning: objtool: __ct_user_enter+0x72: call to __kasan_check_write() leaves .noinstr.text section vmlinux.o: warning: objtool: __ct_user_exit+0x47: call to __kasan_check_write() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) --- kernel/context_tracking.c | 12

[PATCH v3 20/51] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IBRS

vmlinux.o: warning: objtool: intel_idle_ibrs+0x17: call to spec_ctrl_current() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_ibrs+0x27: call to wrmsrl.constprop.0() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked-by: F

[PATCH v3 39/51] arm,omap2: Use WFI for omap2_pm_idle()

arch_cpu_idle() is a very simple idle interface and exposes only a single idle state and is expected to not require RCU and not do any tracing/instrumentation. As such, omap2_pm_idle() is not a valid implementation. Replace it with a simple (shallow) omap2_do_wfi() call. Omap2 doesn't have a cpui

[PATCH v3 37/51] cpuidle,omap3: Push RCU-idle into omap_sram_idle()

OMAP3 uses full SoC suspend modes as idle states, as such it needs the whole power-domain and clock-domain code from the idle path. All that code is not suitable to run with RCU disabled, as such push RCU-idle deeper still. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Tony Lindgren Acked-

[PATCH v3 44/51] entry,kasan,x86: Disallow overriding mem*() functions

KASAN cannot just hijack the mem*() functions, it needs to emit __asan_mem*() variants if it wants instrumentation (other sanitizers already do this). vmlinux.o: warning: objtool: sync_regs+0x24: call to memcpy() leaves .noinstr.text section vmlinux.o: warning: objtool: vc_switch_off_ist+0xbe: ca

Re: [PATCH v3 41/51] cpuidle,clk: Remove trace_.*_rcuidle()

Quoting Peter Zijlstra (2023-01-12 11:43:55) > OMAP was the one and only user. > > Signed-off-by: Peter Zijlstra (Intel) > Reviewed-by: Ulf Hansson > Acked-by: Rafael J. Wysocki > Acked-by: Frederic Weisbecker > Tested-by: Tony Lindgren > Tested-by: Ulf Hansson > --- Acked-by: Stephen Boyd

[PATCH v3 43/51] intel_idle: Add force_irq_on module param

For testing purposes. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- drivers/idle/intel_idle.c |7 ++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/idle/intel_idle.c

[PATCH v3 47/51] cpuidle: Ensure ct_cpuidle_enter() is always called from noinstr/__cpuidle

Tracing (kprobes included) and other compiler instrumentation relies on a normal kernel runtime. Therefore all functions that disable RCU should be noinstr, as should all functions that are called while RCU is disabled. Signed-off-by: Peter Zijlstra (Intel) --- drivers/cpuidle/cpuidle.c | 37 +

[PATCH v3 45/51] sched: Always inline __this_cpu_preempt_check()

vmlinux.o: warning: objtool: in_entry_stack+0x9: call to __this_cpu_preempt_check() leaves .noinstr.text section vmlinux.o: warning: objtool: default_do_nmi+0x10: call to __this_cpu_preempt_check() leaves .noinstr.text section vmlinux.o: warning: objtool: fpu_idle_fpregs+0x41: call to __this_cpu

[PATCH v3 48/51] cpuidle,arch: Mark all ct_cpuidle_enter() callers __cpuidle

For all cpuidle drivers that use CPUIDLE_FLAG_RCU_IDLE, ensure that all functions that call ct_cpuidle_enter() are marked __cpuidle. ( due to lack of noinstr validation on these platforms it is entirely possible this isn't complete ) Signed-off-by: Peter Zijlstra (Intel) --- arch/arm/mach-imx

[PATCH v3 46/51] arm64,riscv,perf: Remove RCU_NONIDLE() usage

The PM notifiers should no longer be ran with RCU disabled (per the previous patches), as such this hack is no longer required either. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- drivers/p

[PATCH v3 49/51] cpuidle,arch: Mark all regular cpuidle_state::enter methods __cpuidle

For all cpuidle drivers that do not use CPUIDLE_FLAG_RCU_IDLE (iow, the simple ones) make sure all the functions are marked __cpuidle. ( due to lack of noinstr validation on these platforms it is entirely possible this isn't complete ) Signed-off-by: Peter Zijlstra (Intel) --- arch/arm/kernel

[PATCH v3 29/51] cpuidle,tdx: Make tdx noinstr clean

vmlinux.o: warning: objtool: __halt+0x2c: call to hcall_func.constprop.0() leaves .noinstr.text section vmlinux.o: warning: objtool: __halt+0x3f: call to __tdx_hypercall() leaves .noinstr.text section vmlinux.o: warning: objtool: __tdx_hypercall+0x66: call to __tdx_hypercall_failed() leaves .noi

[PATCH v3 18/51] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE *again*

vmlinux.o: warning: objtool: intel_idle_irq+0x10c: call to trace_hardirqs_off() leaves .noinstr.text section As per commit 32d4fd5751ea ("cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE"): "must not have tracing in idle functions" Clearly people can't read and tinker along until splat dissa

[PATCH v3 31/51] cpuidle,nospec: Make noinstr clean

vmlinux.o: warning: objtool: mwait_idle+0x47: call to mds_idle_clear_cpu_buffers() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_processor_ffh_cstate_enter+0xa2: call to mds_idle_clear_cpu_buffers() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle+0x91: call t

[PATCH v3 01/51] x86/perf/amd: Remove tracing from perf_lopwr_cb()

The perf_lopwr_cb() is called from the idle routines; there is no RCU there, we must not enter tracing. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- arch/x86/events/amd/brs.c | 13

[PATCH v3 26/51] time/tick-broadcast: Remove RCU_NONIDLE usage

No callers left that have already disabled RCU. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Mark Rutland Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- kernel/time/tick-broadcast-hrtimer.c | 29

[PATCH v3 22/51] x86/tdx: Remove TDX_HCALL_ISSUE_STI

Now that arch_cpu_idle() is expected to return with IRQs disabled, avoid the useless STI/CLI dance. Per the specs this is supposed to work, but nobody has yet relied up this behaviour so broken implementations are possible. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked

[PATCH v3 42/51] ubsan: Fix objtool UACCESS warns

clang-14 allyesconfig gives: vmlinux.o: warning: objtool: emulator_cmpxchg_emulated+0x705: call to __ubsan_handle_load_invalid_value() with UACCESS enabled vmlinux.o: warning: objtool: paging64_update_accessed_dirty_bits+0x39e: call to __ubsan_handle_load_invalid_value() with UACCESS enabled vml

[PATCH v3 19/51] cpuidle,intel_idle: Fix CPUIDLE_FLAG_INIT_XSTATE

vmlinux.o: warning: objtool: intel_idle_s2idle+0xd5: call to fpu_idle_fpregs() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_xstate+0x11: call to fpu_idle_fpregs() leaves .noinstr.text section vmlinux.o: warning: objtool: fpu_idle_fpregs+0x9: call to xfeatures_in_use() lea

[PATCH v3 12/51] cpuidle,dt: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then temporarily enable it again before going idle is daft. Notably: this converts all dt_init_idle_driver() and __CPU_PM_CPU_IDLE_ENTER() users for they are inextrably intertwined. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acke

[PATCH v3 02/51] x86/idle: Replace x86_idle with a static_call

Typical boot time setup; no need to suffer an indirect call for that. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Reviewed-by: Rafael J. Wysocki Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- arch/x86/kernel/process.c | 50 +--

[PATCH v3 09/51] cpuidle,omap3: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then teporarily enable it again before going idle is daft. Notably the cpu_pm_*() calls implicitly re-enable RCU for a bit. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Reviewed-by: Tony Lindgren Acked-by: Rafael J. Wysocki

[PATCH v3 13/51] cpuidle: Fix ct_idle_*() usage

The whole disable-RCU, enable-IRQS dance is very intricate since changing IRQ state is traced, which depends on RCU. Add two helpers for the cpuidle case that mirror the entry code. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony

[PATCH v3 14/51] cpuidle,cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}()

All callers should still have RCU enabled. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Ulf Hansson Acked-by: Mark Rutland Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- kernel/cpu_pm.c |9 - 1 file changed, 9

[PATCH v3 25/51] printk: Remove trace_.*_rcuidle() usage

The problem, per commit fc98c3c8c9dc ("printk: use rcuidle console tracepoint"), was printk usage from the cpuidle path where RCU was already disabled. Per the patches earlier in this series, this is no longer the case. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Sergey Senozhatsky Acked

[PATCH v3 38/51] cpuidle,omap4: Push RCU-idle into omap4_enter_lowpower()

From: Tony Lindgren OMAP4 uses full SoC suspend modes as idle states, as such it needs the whole power-domain and clock-domain code from the idle path. All that code is not suitable to run with RCU disabled, as such push RCU-idle deeper still. Signed-off-by: Tony Lindgren Signed-off-by: Peter

[PATCH v3 10/51] cpuidle,armada: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then temporarily enable it again before going idle is daft. Notably the cpu_pm_*() calls implicitly re-enable RCU for a bit. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Acked-by: Rafael J. Wysocki Tested-by: Tony Lindgren T

[PATCH v3 16/51] cpuidle: Annotate poll_idle()

The __cpuidle functions will become a noinstr class, as such they need explicit annotations. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- drivers/cpuidle/poll_state.c |6 +- 1 fi

[PATCH v3 36/51] cpuidle,omap3: Use WFI for omap3_pm_idle()

arch_cpu_idle() is a very simple idle interface and exposes only a single idle state and is expected to not require RCU and not do any tracing/instrumentation. As such, omap_sram_idle() is not a valid implementation. Replace it with the simple (shallow) omap3_do_wfi() call. Leaving the more compli

[PATCH v3 30/51] cpuidle,xenpv: Make more PARAVIRT_XXL noinstr clean

vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() l

[PATCH v3 32/51] cpuidle,acpi: Make noinstr clean

vmlinux.o: warning: objtool: io_idle+0xc: call to __inb.isra.0() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_idle_enter+0xfe: call to num_online_cpus() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_idle_enter+0x115: call to acpi_idle_fallback_to_c1.isra.0() le

[PATCH v3 33/51] trace: Remove trace_hardirqs_{on,off}_caller()

Per commit 56e62a737028 ("s390: convert to generic entry") the last and only callers of trace_hardirqs_{on,off}_caller() went away, clean up. Cc: Sven Schnelle Signed-off-by: Peter Zijlstra (Intel) --- kernel/trace/trace_preemptirq.c | 29 - 1 file changed, 29 dele

[PATCH v3 28/51] cpuidle,mwait: Make noinstr clean

vmlinux.o: warning: objtool: intel_idle_s2idle+0x6e: call to __monitor.constprop.0() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_irq+0x8c: call to __monitor.constprop.0() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle+0x73: call to __monitor.constpro

[PATCH v3 08/51] cpuidle,imx6: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then temporarily enable it again, at least twice, before going idle is daft. Notably both cpu_pm_enter() and cpu_cluster_pm_enter() implicity re-enable RCU. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Acked-by: Rafael J. Wyso

[PATCH v3 03/51] cpuidle/poll: Ensure IRQ state is invariant

cpuidle_state::enter() methods should be IRQ invariant. Additionally make sure to use raw_local_irq_*() methods since this cpuidle callback will be called with RCU already disabled. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Rafael J. Wysocki Reviewed-by: Frederic Weisbecker Tested-by:

[PATCH v3 24/51] arm64,smp: Remove trace_.*_rcuidle() usage

Ever since commit d3afc7f12987 ("arm64: Allow IPIs to be handled as normal interrupts") this function is called in regular IRQ context. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Mark Rutland Acked-by: Marc Zyngier Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony

[PATCH v3 15/51] acpi_idle: Remove tracing

All the idle routines are called with RCU disabled, as such there must not be any tracing inside. While there; clean-up the io-port idle thing. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson ---

[PATCH v3 21/51] arch/idle: Change arch_cpu_idle() IRQ behaviour

Current arch_cpu_idle() is called with IRQs disabled, but will return with IRQs enabled. However, the very first thing the generic code does after calling arch_cpu_idle() is raw_local_irq_disable(). This means that architectures that can idle with IRQs disabled end up doing a pointless 'enable-dis

[PATCH v3 27/51] cpuidle,sched: Remove annotations from TIF_{POLLING_NRFLAG,NEED_RESCHED}

vmlinux.o: warning: objtool: mwait_idle+0x5: call to current_set_polling_and_test() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_processor_ffh_cstate_enter+0xc5: call to current_set_polling_and_test() leaves .noinstr.text section vmlinux.o: warning: objtool: cpu_idle_poll.isra.0

[PATCH v3 04/51] cpuidle: Move IRQ state validation

Make cpuidle_enter_state() consistent with the s2idle variant and verify ->enter() always returns with interrupts disabled. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- drivers/cpuidle/cpui

[PATCH v3 23/51] arm,smp: Remove trace_.*_rcuidle() usage

None of these functions should ever be ran with RCU disabled anymore. Specifically, do_handle_IPI() is only called from handle_IPI() which explicitly does irq_enter()/irq_exit() which ensures RCU is watching. The problem with smp_cross_call() was, per commit 7c64cc0531fa ("arm: Use _rcuidle for s

[PATCH v3 11/51] cpuidle,omap4: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then temporarily enable it again, some *four* times, before going idle is daft. Notably three times explicitly using RCU_NONIDLE() and once implicitly through cpu_pm_*(). Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Reviewed-b

[PATCH v3 05/51] cpuidle,riscv: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then temporarily enable it again, at least twice, before going idle is daft. That is, once implicitly through the cpu_pm_*() calls and once explicitly doing ct_irq_*_irqon(). Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Anup Patel Reviewed-by: Fr

[PATCH v3 17/51] objtool/idle: Validate __cpuidle code as noinstr

Idle code is very like entry code in that RCU isn't available. As such, add a little validation. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Geert Uytterhoeven Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- arch/alpha/kernel

[PATCH v3 06/51] cpuidle,tegra: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then temporarily enable it again, at least twice, before going idle is daft. Notably once implicitly through the cpu_pm_*() calls and once explicitly doing RCU_NONIDLE(). Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Acked-by:

[PATCH v3 07/51] cpuidle,psci: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then temporarily enable it again, at least twice, before going idle is daft. Notably once implicitly through the cpu_pm_*() calls and once explicitly doing ct_irq_*_irqon(). Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Reviewe