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docs/admin: alphabetize parts of kernel-parameters.txt (part 2)

Alphabetize several of the kernel boot parameters in
kernel-parameters.txt.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

authored by

Randy Dunlap and committed by
Jonathan Corbet
389cfd96 d2fc83c1

+83 -83
+83 -83
Documentation/admin-guide/kernel-parameters.txt
··· 461 461 Format: <io>,<irq>,<mode> 462 462 See header of drivers/net/hamradio/baycom_ser_hdx.c. 463 463 464 + bert_disable [ACPI] 465 + Disable BERT OS support on buggy BIOSes. 466 + 467 + bgrt_disable [ACPI][X86] 468 + Disable BGRT to avoid flickering OEM logo. 469 + 464 470 blkdevparts= Manual partition parsing of block device(s) for 465 471 embedded devices based on command line input. 466 472 See Documentation/block/cmdline-partition.rst ··· 481 475 and this will cause the kernel to look for it. 482 476 483 477 See Documentation/admin-guide/bootconfig.rst 484 - 485 - bert_disable [ACPI] 486 - Disable BERT OS support on buggy BIOSes. 487 - 488 - bgrt_disable [ACPI][X86] 489 - Disable BGRT to avoid flickering OEM logo. 490 478 491 479 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards) 492 480 bttv.radio= Most important insmod options are available as ··· 766 766 0: default value, disable debugging 767 767 1: enable debugging at boot time 768 768 769 + cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver 770 + Format: 771 + <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>] 772 + 773 + cpu0_hotplug [X86] Turn on CPU0 hotplug feature when 774 + CONFIG_BOOTPARAM_HOTPLUG_CPU0 is off. 775 + Some features depend on CPU0. Known dependencies are: 776 + 1. Resume from suspend/hibernate depends on CPU0. 777 + Suspend/hibernate will fail if CPU0 is offline and you 778 + need to online CPU0 before suspend/hibernate. 779 + 2. PIC interrupts also depend on CPU0. CPU0 can't be 780 + removed if a PIC interrupt is detected. 781 + It's said poweroff/reboot may depend on CPU0 on some 782 + machines although I haven't seen such issues so far 783 + after CPU0 is offline on a few tested machines. 784 + If the dependencies are under your control, you can 785 + turn on cpu0_hotplug. 786 + 769 787 cpuidle.off=1 [CPU_IDLE] 770 788 disable the cpuidle sub-system 771 789 ··· 804 786 on every CPU online, such as boot, and resume from suspend. 805 787 Default: 10000 806 788 807 - cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver 808 - Format: 809 - <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>] 789 + crash_kexec_post_notifiers 790 + Run kdump after running panic-notifiers and dumping 791 + kmsg. This only for the users who doubt kdump always 792 + succeeds in any situation. 793 + Note that this also increases risks of kdump failure, 794 + because some panic notifiers can make the crashed 795 + kernel more unstable. 810 796 811 797 crashkernel=size[KMG][@offset[KMG]] 812 798 [KNL] Using kexec, Linux can switch to a 'crash kernel' ··· 1662 1640 hpet_mmap= [X86, HPET_MMAP] Allow userspace to mmap HPET 1663 1641 registers. Default set by CONFIG_HPET_MMAP_DEFAULT. 1664 1642 1665 - hugetlb_cma= [HW,CMA] The size of a CMA area used for allocation 1666 - of gigantic hugepages. Or using node format, the size 1667 - of a CMA area per node can be specified. 1668 - Format: nn[KMGTPE] or (node format) 1669 - <node>:nn[KMGTPE][,<node>:nn[KMGTPE]] 1670 - 1671 - Reserve a CMA area of given size and allocate gigantic 1672 - hugepages using the CMA allocator. If enabled, the 1673 - boot-time allocation of gigantic hugepages is skipped. 1674 - 1675 1643 hugepages= [HW] Number of HugeTLB pages to allocate at boot. 1676 1644 If this follows hugepagesz (below), it specifies 1677 1645 the number of pages of hugepagesz to be allocated. ··· 1682 1670 architecture dependent. See also 1683 1671 Documentation/admin-guide/mm/hugetlbpage.rst. 1684 1672 Format: size[KMG] 1673 + 1674 + hugetlb_cma= [HW,CMA] The size of a CMA area used for allocation 1675 + of gigantic hugepages. Or using node format, the size 1676 + of a CMA area per node can be specified. 1677 + Format: nn[KMGTPE] or (node format) 1678 + <node>:nn[KMGTPE][,<node>:nn[KMGTPE]] 1679 + 1680 + Reserve a CMA area of given size and allocate gigantic 1681 + hugepages using the CMA allocator. If enabled, the 1682 + boot-time allocation of gigantic hugepages is skipped. 1685 1683 1686 1684 hugetlb_free_vmemmap= 1687 1685 [KNL] Reguires CONFIG_HUGETLB_PAGE_FREE_VMEMMAP ··· 2705 2683 If there are multiple matching configurations changing 2706 2684 the same attribute, the last one is used. 2707 2685 2708 - memblock=debug [KNL] Enable memblock debug messages. 2709 - 2710 2686 load_ramdisk= [RAM] [Deprecated] 2711 2687 2712 2688 lockd.nlm_grace_period=P [NFS] Assign grace period. ··· 2945 2925 2946 2926 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel 2947 2927 memory. 2928 + 2929 + memblock=debug [KNL] Enable memblock debug messages. 2948 2930 2949 2931 memchunk=nn[KMG] 2950 2932 [KNL,SH] Allow user to override the default size for ··· 3215 3193 mtdparts= [MTD] 3216 3194 See drivers/mtd/parsers/cmdlinepart.c 3217 3195 3218 - multitce=off [PPC] This parameter disables the use of the pSeries 3219 - firmware feature for updating multiple TCE entries 3220 - at a time. 3221 - 3222 3196 mtdset= [ARM] 3223 3197 ARM/S3C2412 JIVE boot control 3224 3198 ··· 3241 3223 Used for mtrr cleanup. It is spare mtrr entries number. 3242 3224 Set to 2 or more if your graphical card needs more. 3243 3225 3226 + multitce=off [PPC] This parameter disables the use of the pSeries 3227 + firmware feature for updating multiple TCE entries 3228 + at a time. 3229 + 3244 3230 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card 3245 3231 3246 3232 netdev= [NET] Network devices parameters ··· 3253 3231 something different and driver-specific. 3254 3232 This usage is only documented in each driver source 3255 3233 file if at all. 3234 + 3235 + netpoll.carrier_timeout= 3236 + [NET] Specifies amount of time (in seconds) that 3237 + netpoll should wait for a carrier. By default netpoll 3238 + waits 4 seconds. 3256 3239 3257 3240 nf_conntrack.acct= 3258 3241 [NETFILTER] Enable connection tracking flow accounting ··· 3408 3381 3409 3382 These settings can be accessed at runtime via 3410 3383 the nmi_watchdog and hardlockup_panic sysctls. 3411 - 3412 - netpoll.carrier_timeout= 3413 - [NET] Specifies amount of time (in seconds) that 3414 - netpoll should wait for a carrier. By default netpoll 3415 - waits 4 seconds. 3416 3384 3417 3385 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths 3418 3386 emulation library even if a 387 maths coprocessor ··· 3700 3678 3701 3679 nox2apic [X86-64,APIC] Do not enable x2APIC mode. 3702 3680 3703 - cpu0_hotplug [X86] Turn on CPU0 hotplug feature when 3704 - CONFIG_BOOTPARAM_HOTPLUG_CPU0 is off. 3705 - Some features depend on CPU0. Known dependencies are: 3706 - 1. Resume from suspend/hibernate depends on CPU0. 3707 - Suspend/hibernate will fail if CPU0 is offline and you 3708 - need to online CPU0 before suspend/hibernate. 3709 - 2. PIC interrupts also depend on CPU0. CPU0 can't be 3710 - removed if a PIC interrupt is detected. 3711 - It's said poweroff/reboot may depend on CPU0 on some 3712 - machines although I haven't seen such issues so far 3713 - after CPU0 is offline on a few tested machines. 3714 - If the dependencies are under your control, you can 3715 - turn on cpu0_hotplug. 3716 - 3717 3681 nps_mtm_hs_ctr= [KNL,ARC] 3718 3682 This parameter sets the maximum duration, in 3719 3683 cycles, each HW thread of the CTOP can run ··· 3831 3823 3832 3824 panic_on_warn panic() instead of WARN(). Useful to cause kdump 3833 3825 on a WARN(). 3834 - 3835 - crash_kexec_post_notifiers 3836 - Run kdump after running panic-notifiers and dumping 3837 - kmsg. This only for the users who doubt kdump always 3838 - succeeds in any situation. 3839 - Note that this also increases risks of kdump failure, 3840 - because some panic notifiers can make the crashed 3841 - kernel more unstable. 3842 3826 3843 3827 parkbd.port= [HW] Parallel port number the keyboard adapter is 3844 3828 connected to, default is 0. ··· 5877 5877 This will guarantee that all the other pcrs 5878 5878 are saved. 5879 5879 5880 + tp_printk [FTRACE] 5881 + Have the tracepoints sent to printk as well as the 5882 + tracing ring buffer. This is useful for early boot up 5883 + where the system hangs or reboots and does not give the 5884 + option for reading the tracing buffer or performing a 5885 + ftrace_dump_on_oops. 5886 + 5887 + To turn off having tracepoints sent to printk, 5888 + echo 0 > /proc/sys/kernel/tracepoint_printk 5889 + Note, echoing 1 into this file without the 5890 + tracepoint_printk kernel cmdline option has no effect. 5891 + 5892 + The tp_printk_stop_on_boot (see below) can also be used 5893 + to stop the printing of events to console at 5894 + late_initcall_sync. 5895 + 5896 + ** CAUTION ** 5897 + 5898 + Having tracepoints sent to printk() and activating high 5899 + frequency tracepoints such as irq or sched, can cause 5900 + the system to live lock. 5901 + 5902 + tp_printk_stop_on_boot [FTRACE] 5903 + When tp_printk (above) is set, it can cause a lot of noise 5904 + on the console. It may be useful to only include the 5905 + printing of events during boot up, as user space may 5906 + make the system inoperable. 5907 + 5908 + This command line option will stop the printing of events 5909 + to console at the late_initcall_sync() time frame. 5910 + 5880 5911 trace_buf_size=nn[KMG] 5881 5912 [FTRACE] will set tracing buffer size on each cpu. 5882 5913 ··· 5954 5923 5955 5924 See also Documentation/trace/ftrace.rst "trace options" 5956 5925 section. 5957 - 5958 - tp_printk [FTRACE] 5959 - Have the tracepoints sent to printk as well as the 5960 - tracing ring buffer. This is useful for early boot up 5961 - where the system hangs or reboots and does not give the 5962 - option for reading the tracing buffer or performing a 5963 - ftrace_dump_on_oops. 5964 - 5965 - To turn off having tracepoints sent to printk, 5966 - echo 0 > /proc/sys/kernel/tracepoint_printk 5967 - Note, echoing 1 into this file without the 5968 - tracepoint_printk kernel cmdline option has no effect. 5969 - 5970 - The tp_printk_stop_on_boot (see below) can also be used 5971 - to stop the printing of events to console at 5972 - late_initcall_sync. 5973 - 5974 - ** CAUTION ** 5975 - 5976 - Having tracepoints sent to printk() and activating high 5977 - frequency tracepoints such as irq or sched, can cause 5978 - the system to live lock. 5979 - 5980 - tp_printk_stop_on_boot [FTRACE] 5981 - When tp_printk (above) is set, it can cause a lot of noise 5982 - on the console. It may be useful to only include the 5983 - printing of events during boot up, as user space may 5984 - make the system inoperable. 5985 - 5986 - This command line option will stop the printing of events 5987 - to console at the late_initcall_sync() time frame. 5988 5926 5989 5927 traceoff_on_warning 5990 5928 [FTRACE] enable this option to disable tracing when a