]> Pileus Git - ~andy/linux/blobdiff - Documentation/kernel-parameters.txt
Merge branch 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[~andy/linux] / Documentation / kernel-parameters.txt
index 773fc4c077b4d8ac51d91f149ee83b519861bcab..4252af6ffda18da2559054fdb9b42316afe6e891 100644 (file)
@@ -774,6 +774,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
        disable=        [IPV6]
                        See Documentation/networking/ipv6.txt.
 
+       disable_cpu_apicid= [X86,APIC,SMP]
+                       Format: <int>
+                       The number of initial APIC ID for the
+                       corresponding CPU to be disabled at boot,
+                       mostly used for the kdump 2nd kernel to
+                       disable BSP to wake up multiple CPUs without
+                       causing system reset or hang due to sending
+                       INIT from AP to BSP.
+
        disable_ddw     [PPC/PSERIES]
                        Disable Dynamic DMA Window support. Use this if
                        to workaround buggy firmware.
@@ -847,6 +856,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
        earlyprintk=    [X86,SH,BLACKFIN,ARM]
                        earlyprintk=vga
+                       earlyprintk=efi
                        earlyprintk=xen
                        earlyprintk=serial[,ttySn[,baudrate]]
                        earlyprintk=serial[,0x...[,baudrate]]
@@ -860,7 +870,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        Append ",keep" to not disable it when the real console
                        takes over.
 
-                       Only vga or serial or usb debug port at a time.
+                       Only one of vga, efi, serial, or usb debug port can
+                       be used at a time.
 
                        Currently only ttyS0 and ttyS1 may be specified by
                        name.  Other I/O ports may be explicitly specified
@@ -874,11 +885,19 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        Interaction with the standard serial driver is not
                        very good.
 
-                       The VGA output is eventually overwritten by the real
-                       console.
+                       The VGA and EFI output is eventually overwritten by
+                       the real console.
 
                        The xen output can only be used by Xen PV guests.
 
+       edac_report=    [HW,EDAC] Control how to report EDAC event
+                       Format: {"on" | "off" | "force"}
+                       on: enable EDAC to report H/W event. May be overridden
+                       by other higher priority error reporting module.
+                       off: disable H/W event reporting through EDAC.
+                       force: enforce the use of EDAC to report H/W event.
+                       default: on.
+
        ekgdboc=        [X86,KGDB] Allow early kernel console debugging
                        ekgdboc=kbd
 
@@ -888,6 +907,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
        edd=            [EDD]
                        Format: {"off" | "on" | "skip[mbr]"}
 
+       efi=            [EFI]
+                       Format: { "old_map" }
+                       old_map [X86-64]: switch to the old ioremap-based EFI
+                       runtime services mapping. 32-bit still uses this one by
+                       default.
+
        efi_no_storage_paranoia [EFI; X86]
                        Using this parameter you can use more than 50% of
                        your efi variable storage. Use this parameter only if
@@ -1068,6 +1093,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                                VIA, nVidia)
                        verbose: show contents of HPET registers during setup
 
+       hpet_mmap=      [X86, HPET_MMAP] Allow userspace to mmap HPET
+                       registers.  Default set by CONFIG_HPET_MMAP_DEFAULT.
+
        hugepages=      [HW,X86-32,IA-64] HugeTLB pages to allocate at boot.
        hugepagesz=     [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages.
                        On x86-64 and powerpc, this option can be specified
@@ -1185,15 +1213,24 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        owned by uid=0.
 
        ima_hash=       [IMA]
-                       Format: { "sha1" | "md5" }
+                       Format: { md5 | sha1 | rmd160 | sha256 | sha384
+                                  | sha512 | ... }
                        default: "sha1"
 
+                       The list of supported hash algorithms is defined
+                       in crypto/hash_info.h.
+
        ima_tcb         [IMA]
                        Load a policy which meets the needs of the Trusted
                        Computing Base.  This means IMA will measure all
                        programs exec'd, files mmap'd for exec, and all files
                        opened for read by uid=0.
 
+       ima_template=   [IMA]
+                       Select one of defined IMA measurements template formats.
+                       Formats: { "ima" | "ima-ng" }
+                       Default: "ima-ng"
+
        init=           [KNL]
                        Format: <full_path>
                        Run specified binary instead of /sbin/init as init
@@ -1515,6 +1552,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
                        * atapi_dmadir: Enable ATAPI DMADIR bridge support
 
+                       * disable: Disable this device.
+
                        If there are multiple matching configurations changing
                        the same attribute, the last one is used.
 
@@ -1773,6 +1812,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        that the amount of memory usable for all allocations
                        is not too small.
 
+       movable_node    [KNL,X86] Boot-time switch to enable the effects
+                       of CONFIG_MOVABLE_NODE=y. See mm/Kconfig for details.
+
        MTD_Partition=  [MTD]
                        Format: <name>,<region-number>,<size>,<offset>
 
@@ -2603,7 +2645,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
        ramdisk_size=   [RAM] Sizes of RAM disks in kilobytes
                        See Documentation/blockdev/ramdisk.txt.
 
-       rcu_nocbs=      [KNL,BOOT]
+       rcu_nocbs=      [KNL]
                        In kernels built with CONFIG_RCU_NOCB_CPU=y, set
                        the specified list of CPUs to be no-callback CPUs.
                        Invocation of these CPUs' RCU callbacks will
@@ -2612,11 +2654,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        for RCU-preempt, and "s" for RCU-sched, and "N"
                        is the CPU number.  This reduces OS jitter on the
                        offloaded CPUs, which can be useful for HPC and
-
                        real-time workloads.  It can also improve energy
                        efficiency for asymmetric multiprocessors.
 
-       rcu_nocb_poll   [KNL,BOOT]
+       rcu_nocb_poll   [KNL]
                        Rather than requiring that offloaded CPUs
                        (specified by rcu_nocbs= above) explicitly
                        awaken the corresponding "rcuoN" kthreads,
@@ -2627,126 +2668,145 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        energy efficiency by requiring that the kthreads
                        periodically wake up to do the polling.
 
-       rcutree.blimit= [KNL,BOOT]
-                       Set maximum number of finished RCU callbacks to process
-                       in one batch.
+       rcutree.blimit= [KNL]
+                       Set maximum number of finished RCU callbacks to
+                       process in one batch.
 
-       rcutree.fanout_leaf=    [KNL,BOOT]
+       rcutree.rcu_fanout_leaf= [KNL]
                        Increase the number of CPUs assigned to each
                        leaf rcu_node structure.  Useful for very large
                        systems.
 
-       rcutree.jiffies_till_first_fqs= [KNL,BOOT]
+       rcutree.jiffies_till_first_fqs= [KNL]
                        Set delay from grace-period initialization to
                        first attempt to force quiescent states.
                        Units are jiffies, minimum value is zero,
                        and maximum value is HZ.
 
-       rcutree.jiffies_till_next_fqs= [KNL,BOOT]
+       rcutree.jiffies_till_next_fqs= [KNL]
                        Set delay between subsequent attempts to force
                        quiescent states.  Units are jiffies, minimum
                        value is one, and maximum value is HZ.
 
-       rcutree.qhimark=        [KNL,BOOT]
-                       Set threshold of queued
-                       RCU callbacks over which batch limiting is disabled.
+       rcutree.qhimark= [KNL]
+                       Set threshold of queued RCU callbacks beyond which
+                       batch limiting is disabled.
 
-       rcutree.qlowmark=       [KNL,BOOT]
+       rcutree.qlowmark= [KNL]
                        Set threshold of queued RCU callbacks below which
                        batch limiting is re-enabled.
 
-       rcutree.rcu_cpu_stall_suppress= [KNL,BOOT]
-                       Suppress RCU CPU stall warning messages.
-
-       rcutree.rcu_cpu_stall_timeout= [KNL,BOOT]
-                       Set timeout for RCU CPU stall warning messages.
-
-       rcutree.rcu_idle_gp_delay=      [KNL,BOOT]
+       rcutree.rcu_idle_gp_delay= [KNL]
                        Set wakeup interval for idle CPUs that have
                        RCU callbacks (RCU_FAST_NO_HZ=y).
 
-       rcutree.rcu_idle_lazy_gp_delay= [KNL,BOOT]
+       rcutree.rcu_idle_lazy_gp_delay= [KNL]
                        Set wakeup interval for idle CPUs that have
                        only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y).
                        Lazy RCU callbacks are those which RCU can
                        prove do nothing more than free memory.
 
-       rcutorture.fqs_duration= [KNL,BOOT]
+       rcutorture.fqs_duration= [KNL]
                        Set duration of force_quiescent_state bursts.
 
-       rcutorture.fqs_holdoff= [KNL,BOOT]
+       rcutorture.fqs_holdoff= [KNL]
                        Set holdoff time within force_quiescent_state bursts.
 
-       rcutorture.fqs_stutter= [KNL,BOOT]
+       rcutorture.fqs_stutter= [KNL]
                        Set wait time between force_quiescent_state bursts.
 
-       rcutorture.irqreader= [KNL,BOOT]
-                       Test RCU readers from irq handlers.
+       rcutorture.gp_exp= [KNL]
+                       Use expedited update-side primitives.
 
-       rcutorture.n_barrier_cbs= [KNL,BOOT]
+       rcutorture.gp_normal= [KNL]
+                       Use normal (non-expedited) update-side primitives.
+                       If both gp_exp and gp_normal are set, do both.
+                       If neither gp_exp nor gp_normal are set, still
+                       do both.
+
+       rcutorture.n_barrier_cbs= [KNL]
                        Set callbacks/threads for rcu_barrier() testing.
 
-       rcutorture.nfakewriters= [KNL,BOOT]
+       rcutorture.nfakewriters= [KNL]
                        Set number of concurrent RCU writers.  These just
                        stress RCU, they don't participate in the actual
                        test, hence the "fake".
 
-       rcutorture.nreaders= [KNL,BOOT]
+       rcutorture.nreaders= [KNL]
                        Set number of RCU readers.
 
-       rcutorture.onoff_holdoff= [KNL,BOOT]
+       rcutorture.object_debug= [KNL]
+                       Enable debug-object double-call_rcu() testing.
+
+       rcutorture.onoff_holdoff= [KNL]
                        Set time (s) after boot for CPU-hotplug testing.
 
-       rcutorture.onoff_interval= [KNL,BOOT]
+       rcutorture.onoff_interval= [KNL]
                        Set time (s) between CPU-hotplug operations, or
                        zero to disable CPU-hotplug testing.
 
-       rcutorture.shuffle_interval= [KNL,BOOT]
+       rcutorture.rcutorture_runnable= [BOOT]
+                       Start rcutorture running at boot time.
+
+       rcutorture.shuffle_interval= [KNL]
                        Set task-shuffle interval (s).  Shuffling tasks
                        allows some CPUs to go into dyntick-idle mode
                        during the rcutorture test.
 
-       rcutorture.shutdown_secs= [KNL,BOOT]
+       rcutorture.shutdown_secs= [KNL]
                        Set time (s) after boot system shutdown.  This
                        is useful for hands-off automated testing.
 
-       rcutorture.stall_cpu= [KNL,BOOT]
+       rcutorture.stall_cpu= [KNL]
                        Duration of CPU stall (s) to test RCU CPU stall
                        warnings, zero to disable.
 
-       rcutorture.stall_cpu_holdoff= [KNL,BOOT]
+       rcutorture.stall_cpu_holdoff= [KNL]
                        Time to wait (s) after boot before inducing stall.
 
-       rcutorture.stat_interval= [KNL,BOOT]
+       rcutorture.stat_interval= [KNL]
                        Time (s) between statistics printk()s.
 
-       rcutorture.stutter= [KNL,BOOT]
+       rcutorture.stutter= [KNL]
                        Time (s) to stutter testing, for example, specifying
                        five seconds causes the test to run for five seconds,
                        wait for five seconds, and so on.  This tests RCU's
                        ability to transition abruptly to and from idle.
 
-       rcutorture.test_boost= [KNL,BOOT]
+       rcutorture.test_boost= [KNL]
                        Test RCU priority boosting?  0=no, 1=maybe, 2=yes.
                        "Maybe" means test if the RCU implementation
                        under test support RCU priority boosting.
 
-       rcutorture.test_boost_duration= [KNL,BOOT]
+       rcutorture.test_boost_duration= [KNL]
                        Duration (s) of each individual boost test.
 
-       rcutorture.test_boost_interval= [KNL,BOOT]
+       rcutorture.test_boost_interval= [KNL]
                        Interval (s) between each boost test.
 
-       rcutorture.test_no_idle_hz= [KNL,BOOT]
+       rcutorture.test_no_idle_hz= [KNL]
                        Test RCU's dyntick-idle handling.  See also the
                        rcutorture.shuffle_interval parameter.
 
-       rcutorture.torture_type= [KNL,BOOT]
+       rcutorture.torture_type= [KNL]
                        Specify the RCU implementation to test.
 
-       rcutorture.verbose= [KNL,BOOT]
+       rcutorture.verbose= [KNL]
                        Enable additional printk() statements.
 
+       rcupdate.rcu_expedited= [KNL]
+                       Use expedited grace-period primitives, for
+                       example, synchronize_rcu_expedited() instead
+                       of synchronize_rcu().  This reduces latency,
+                       but can increase CPU utilization, degrade
+                       real-time latency, and degrade energy efficiency.
+
+       rcupdate.rcu_cpu_stall_suppress= [KNL]
+                       Suppress RCU CPU stall warning messages.
+
+       rcupdate.rcu_cpu_stall_timeout= [KNL]
+                       Set timeout for RCU CPU stall warning messages.
+
        rdinit=         [KNL]
                        Format: <full_path>
                        Run specified binary instead of /init from the ramdisk,
@@ -3475,11 +3535,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        default x2apic cluster mode on platforms
                        supporting x2apic.
 
-       x86_mrst_timer= [X86-32,APBT]
-                       Choose timer option for x86 Moorestown MID platform.
+       x86_intel_mid_timer= [X86-32,APBT]
+                       Choose timer option for x86 Intel MID platform.
                        Two valid options are apbt timer only and lapic timer
                        plus one apbt timer for broadcast timer.
-                       x86_mrst_timer=apbt_only | lapic_and_apbt
+                       x86_intel_mid_timer=apbt_only | lapic_and_apbt
 
        xen_emul_unplug=                [HW,X86,XEN]
                        Unplug Xen emulated devices