linux/arch/powerpc/kernel
Nicholas Piggin e012c49998 powerpc/watchdog: help remote CPUs to flush NMI printk output
The printk layer at the moment does not seem to have a good way to force
flush printk messages that are created in NMI context, except in the
panic path.

NMI-context printk messages normally get to the console with irq_work,
but that won't help if the CPU is stuck with irqs disabled, as can be
the case for hard lockup watchdog messages.

The watchdog currently flushes the printk buffers after detecting a
lockup on remote CPUs, but they may not have processed their NMI IPI
yet by that stage, or they may have self-detected a lockup in which
case they won't go via this NMI IPI path.

Improve the situation by having NMI-context mark a flag if it called
printk, and have watchdog timer interrupts check if that flag was set
and try to flush if it was. Latency is not a big problem because we
were already stuck for a while, just need to try to make sure the
messages eventually make it out.

Depends-on: 5d5e4522a7 ("printk: restore flushing of NMI buffers on remote CPUs after NMI backtraces")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211119113146.752759-6-npiggin@gmail.com
2021-11-29 23:08:43 +11:00
..
ptrace powerpc: Add dear as a synonym for pt_regs.dar register 2021-08-26 21:21:07 +10:00
syscalls compat: remove some compat entry points 2021-09-08 15:32:35 -07:00
trace powerpc/ftrace: Activate HAVE_DYNAMIC_FTRACE_WITH_REGS on PPC32 2021-11-29 22:49:29 +11:00
vdso32 powerpc updates for 5.13 2021-04-30 12:22:28 -07:00
vdso64 powerpc/vdso: Don't use r30 to avoid breaking Go lang 2021-07-29 23:13:12 +10:00
.gitignore
align.c powerpc: warn on emulation of dcbz instruction in kernel mode 2021-10-22 15:22:05 +11:00
asm-offsets.c powerpc: smp: remove hack to obtain offset of task_struct::cpu 2021-09-30 16:13:11 +02:00
audit.c Revert "powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC" 2021-10-27 22:30:32 +11:00
btext.c powerpc/btext: add missing of_node_put 2021-11-25 11:25:29 +11:00
cacheinfo.c powerpc/smp: Use existing L2 cache_map cpumask to find L3 cache siblings 2021-08-04 10:53:39 +10:00
cacheinfo.h
compat_audit.c Revert "powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC" 2021-10-27 22:30:32 +11:00
cpu_setup_6xx.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
cpu_setup_44x.S
cpu_setup_fsl_booke.S powerpc: Retire e200 core (mpc555x processor) 2020-12-05 21:49:18 +11:00
cpu_setup_pa6t.S
cpu_setup_power.c powerpc/64s: Always set PMU control registers to frozen/disabled when not in use 2021-11-24 21:08:57 +11:00
cpu_setup_ppc970.S
cputable.c arch: powerpc: Stop building and using oprofile 2021-01-29 10:05:51 +05:30
crash_dump.c powerpc: Don't use 'struct ppc_inst' to reference instruction location 2021-06-17 00:09:00 +10:00
dawr.c powerpc: rename powerpc_debugfs_root to arch_debugfs_dir 2021-08-13 22:04:26 +10:00
dbell.c powerpc: handle irq_enter/irq_exit in interrupt handler wrappers 2021-02-09 00:10:49 +11:00
dma-iommu.c powerpc/iommu: Report the correct most efficient DMA mask for PCI devices 2021-09-30 17:10:17 +10:00
dma-mask.c
dma-swiotlb.c
dt_cpu_ftrs.c powerpc/64s: Always set PMU control registers to frozen/disabled when not in use 2021-11-24 21:08:57 +11:00
early_32.c
eeh_cache.c powerpc: rename powerpc_debugfs_root to arch_debugfs_dir 2021-08-13 22:04:26 +10:00
eeh_driver.c powerpc/eeh: Use a goto for recovery failures 2021-11-25 11:25:31 +11:00
eeh_event.c
eeh_pe.c powerpc/eeh: Delete eeh_pe->config_addr 2020-10-07 22:34:47 +11:00
eeh_sysfs.c powerpc/eeh: Pass eeh_dev to eeh_ops->resume_notify() 2020-07-26 23:34:20 +10:00
eeh.c pci-v5.16-changes 2021-11-06 14:36:12 -07:00
entry_32.S powerpc/32: indirect function call use bctrl rather than blrl in ret_from_kernel_thread 2021-08-25 13:35:47 +10:00
entry_64.S powerpc/bug: Provide better flexibility to WARN_ON/__WARN_FLAGS() with asm goto 2021-08-15 13:49:24 +10:00
epapr_hcalls.S
epapr_paravirt.c powerpc: Don't use 'struct ppc_inst' to reference instruction location 2021-06-17 00:09:00 +10:00
exceptions-64e.S powerpc/64e: Get dear offset with _DEAR macro 2021-08-26 21:21:07 +10:00
exceptions-64s.S powerpc/64s: Fix unrecoverable MCE calling async handler from NMI 2021-10-07 19:54:55 +11:00
fadump.c powerpc: rename powerpc_debugfs_root to arch_debugfs_dir 2021-08-13 22:04:26 +10:00
firmware.c powerpc: fix unbalanced node refcount in check_kvm_guest() 2021-10-09 00:15:59 +11:00
fpu.S powerpc/32: Remove unneccessary calculations in load_up_{fpu/altivec} 2021-08-18 23:49:55 +10:00
fsl_booke_entry_mapping.S powerpc/booke: Avoid link stack corruption in several places 2021-08-25 13:35:47 +10:00
head_8xx.S powerpc/8xx: Fix pinned TLBs with CONFIG_STRICT_KERNEL_RWX 2021-11-16 21:37:10 +11:00
head_32.h powerpc/32: Reduce code duplication of system call entry 2021-06-25 00:07:10 +10:00
head_40x.S powerpc: Define swapper_pg_dir[] in C 2021-06-17 00:09:10 +10:00
head_44x.S powerpc/booke: Avoid link stack corruption in several places 2021-08-25 13:35:47 +10:00
head_64.S powerpc/kexec: blacklist functions called in real mode for kprobe 2021-07-26 20:38:51 +10:00
head_book3s_32.S powerpc/32s: Fix napping restore in data storage interrupt (DSI) 2021-08-07 08:53:59 +10:00
head_booke.h powerpc/32e: Ignore ESR in instruction storage interrupt handler 2021-10-29 23:12:37 +11:00
head_fsl_booke.S powerpc updates for 5.15 2021-09-03 11:22:50 -07:00
hw_breakpoint_constraints.c powerpc/breakpoint: Cleanup 2021-10-22 15:22:06 +11:00
hw_breakpoint.c powerpc: rename powerpc_debugfs_root to arch_debugfs_dir 2021-08-13 22:04:26 +10:00
idle_6xx.S powerpc/32: Return directly from power_save_ppc32_restore() 2021-03-29 13:22:10 +11:00
idle_book3e.S
idle_book3s.S powerpc/idle: Don't corrupt back chain when going idle 2021-10-20 21:37:58 +11:00
idle_e500.S powerpc/32: Return directly from power_save_ppc32_restore() 2021-03-29 13:22:10 +11:00
idle.c sched/idle: Fix arch_cpu_idle() vs tracing 2020-11-24 16:47:35 +01:00
ima_arch.c
interrupt_64.S powerpc/64s: system call scv tabort fix for corrupt irq soft-mask state 2021-09-13 22:34:11 +10:00
interrupt.c powerpc/64s/interrupt: Fix check_return_regs_valid() false positive 2021-10-27 22:33:47 +11:00
io-workarounds.c powerpc: Fix reverse map real-mode address lookup with huge vmalloc 2021-05-28 22:54:27 +10:00
io.c
iomap.c powerpc: inline iomap accessors 2020-12-04 01:01:09 +11:00
iommu.c powerpc updates for 5.15 2021-09-03 11:22:50 -07:00
irq.c powerpc/64: warn if local irqs are enabled in NMI or hardirq context 2021-10-07 19:54:55 +11:00
isa-bridge.c mm/vmalloc: remove unmap_kernel_range 2021-04-30 11:20:40 -07:00
jump_label.c powerpc: Don't use 'struct ppc_inst' to reference instruction location 2021-06-17 00:09:00 +10:00
kdebugfs.c powerpc: rename powerpc_debugfs_root to arch_debugfs_dir 2021-08-13 22:04:26 +10:00
kgdb.c powerpc/64s: avoid reloading (H)SRR registers if they are still valid 2021-06-25 00:06:55 +10:00
kprobes-ftrace.c ftrace: disable preemption when recursion locked 2021-10-27 11:21:49 -04:00
kprobes.c kprobes: treewide: Make it harder to refer kretprobe_trampoline directly 2021-09-30 21:24:06 -04:00
kvm_emul.S
kvm.c gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable} 2021-10-18 16:33:03 +02:00
l2cr_6xx.S powerpc: Drop SYNC_601() ISYNC_601() and SYNC() 2020-10-08 21:17:13 +11:00
legacy_serial.c powerpc/legacy_serial: Fix UBSAN: array-index-out-of-bounds 2021-05-12 11:07:39 +10:00
Makefile powerpc: clean vdso32 and vdso64 directories 2021-11-15 15:46:45 +11:00
mce_power.c powerpc/powernv: Fix machine check reporting of async store errors 2021-06-21 21:13:19 +10:00
mce.c powerpc/mce: Fix access error in mce handler 2021-09-13 22:34:12 +10:00
misc_32.S powerpc: Avoid link stack corruption in misc asm functions 2021-08-25 13:35:47 +10:00
misc_64.S powerpc: Avoid link stack corruption in misc asm functions 2021-08-25 13:35:47 +10:00
misc.S powerpc: Avoid link stack corruption in misc asm functions 2021-08-25 13:35:47 +10:00
module_32.c powerpc/ftrace: Activate HAVE_DYNAMIC_FTRACE_WITH_REGS on PPC32 2021-11-29 22:49:29 +11:00
module_64.c powerpc/modules: Use PPC_RAW_xx() macros 2021-06-16 00:16:48 +10:00
module.c powerpc/modules: Make module_alloc() Strict Module RWX aware 2021-06-21 21:13:20 +10:00
msi.c
note.S
nvram_64.c printk: introduce a kmsg_dump iterator 2021-03-08 11:43:27 +01:00
of_platform.c powerpc/eeh: Remove eeh_dev_phb_init_dynamic() 2020-07-26 23:34:19 +10:00
optprobes_head.S powerpc: Enable OPTPROBES on PPC32 2021-04-21 22:52:32 +10:00
optprobes.c kprobes: treewide: Make it harder to refer kretprobe_trampoline directly 2021-09-30 21:24:06 -04:00
paca.c memblock: rename memblock_free to memblock_phys_free 2021-11-06 13:30:41 -07:00
pci_32.c
pci_64.c mm/vmalloc: remove unmap_kernel_range 2021-04-30 11:20:40 -07:00
pci_dn.c powerpc/pci: Move PHB discovery for PCI_DN using platforms 2021-02-09 00:01:05 +11:00
pci_of_scan.c
pci-common.c PCI: Rename pcibios_add_device() to pcibios_device_add() 2021-09-21 15:26:09 -05:00
pci-hotplug.c
pmc.c
ppc32.h
ppc_save_regs.S
proc_powerpc.c
process.c KVM: PPC: Book3S HV P9: Use Linux SPR save/restore to manage some host SPRs 2021-11-24 21:09:01 +11:00
prom_init_check.sh
prom_init.c powerpc/prom_init: Fix improper check of prom_getprop() 2021-11-25 11:25:33 +11:00
prom_parse.c
prom.c Kbuild updates for v5.15 2021-09-03 15:33:47 -07:00
reloc_32.S powerpc: Avoid link stack corruption in misc asm functions 2021-08-25 13:35:47 +10:00
reloc_64.S
rtas_flash.c
rtas_pci.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
rtas-proc.c powerpc/rtas: rename RTAS_RMOBUF_MAX to RTAS_USER_REGION_SIZE 2021-04-14 23:04:16 +10:00
rtas-rtc.c powerpc/rtas-rtc: remove unused constant 2021-06-25 14:47:20 +10:00
rtas.c powerpc/rtas: rtas_busy_delay_time() kernel-doc 2021-11-25 11:25:33 +11:00
rtasd.c powerpc: Replace deprecated CPU-hotplug functions. 2021-08-10 23:14:56 +10:00
secure_boot.c powerpc/pseries: Detect secure and trusted boot state of the system. 2020-07-16 14:49:53 +10:00
security.c powerpc/security: Add a helper to query stf_barrier type 2021-10-07 19:52:58 +11:00
secvar-ops.c
secvar-sysfs.c
setup_32.c powerpc: Don't use 'struct ppc_inst' to reference instruction location 2021-06-17 00:09:00 +10:00
setup_64.c mm/memory_hotplug: remove CONFIG_MEMORY_HOTPLUG_SPARSE 2021-11-06 13:30:42 -07:00
setup-common.c powerpc: Mark probe_machine() __init and static 2021-11-29 22:49:26 +11:00
setup.h powerpc: remove unneeded semicolons 2021-02-09 00:10:50 +11:00
signal_32.c signal: Replace force_fatal_sig with force_exit_sig when in doubt 2021-11-19 09:15:58 -06:00
signal_64.c signal: Replace force_fatal_sig with force_exit_sig when in doubt 2021-11-19 09:15:58 -06:00
signal.c entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume() 2021-09-22 10:24:01 -04:00
signal.h powerpc/signal32: Fix sigset_t copy 2021-11-16 21:24:16 +11:00
smp-tbsync.c
smp.c powerpc/smp: Move setup_profiling_timer() under CONFIG_PROFILING 2021-11-29 22:49:23 +11:00
stacktrace.c kprobes: treewide: Make it harder to refer kretprobe_trampoline directly 2021-09-30 21:24:06 -04:00
static_call.c powerpc/32: Add support for out-of-line static calls 2021-10-22 15:22:05 +11:00
suspend.c
swsusp_32.S powerpc/32: Blacklist functions running with MMU disabled for kprobe 2020-06-02 20:59:11 +10:00
swsusp_64.c powerpc/machdep: Remove stale functions from ppc_md structure 2021-10-22 15:22:05 +11:00
swsusp_asm64.S powerpc/machdep: Remove stale functions from ppc_md structure 2021-10-22 15:22:05 +11:00
swsusp_booke.S
swsusp.c
sys_ppc32.c powerpc/compat_sys: swap hi/lo parts of 64-bit syscall args in LE mode 2021-02-11 23:35:07 +11:00
syscalls.c powerpc/syscalls: Simplify do_mmap2() 2021-08-25 13:35:48 +10:00
sysfs.c powerpc/cpuhp: BUG -> WARN conversion in offline path 2021-10-09 00:16:00 +11:00
systbl_chk.sh
systbl.S powerpc/syscalls: switch to generic syscalltbl.sh 2021-04-14 23:04:16 +10:00
tau_6xx.c powerpc/tau: Add 'static' storage qualifier to 'tau_work' definition 2021-08-20 17:00:53 +10:00
time.c powerpc/time: add API for KVM to re-arm the host timer/decrementer 2021-11-24 21:08:57 +11:00
tm.S powerpc/tm: Save and restore AMR on treclaim and trechkpt 2020-10-06 23:22:25 +11:00
traps.c powerpc/64s: Fix unrecoverable MCE calling async handler from NMI 2021-10-07 19:54:55 +11:00
ucall.S
udbg_16550.c powerpc/microwatt: Use standard 16550 UART for console 2021-06-21 21:16:31 +10:00
udbg.c isystem: ship and use stdarg.h 2021-08-19 09:02:55 +09:00
uprobes.c powerpc/64s: avoid reloading (H)SRR registers if they are still valid 2021-06-25 00:06:55 +10:00
vdso32_wrapper.S powerpc/vdso: fix unnecessary rebuilds of vgettimeofday.o 2021-01-30 22:23:42 +11:00
vdso64_wrapper.S powerpc/vdso: fix unnecessary rebuilds of vgettimeofday.o 2021-01-30 22:23:42 +11:00
vdso.c powerpc/vdso: Add support for time namespaces 2021-04-14 23:04:44 +10:00
vecemu.c
vector.S powerpc/32: Remove unneccessary calculations in load_up_{fpu/altivec} 2021-08-18 23:49:55 +10:00
vmlinux.lds.S powerpc: Don't bother about .data..Lubsan sections 2021-11-29 22:49:29 +11:00
watchdog.c powerpc/watchdog: help remote CPUs to flush NMI printk output 2021-11-29 23:08:43 +11:00