Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[firefly-linux-kernel-4.4.55.git] / Documentation / kernel-parameters.txt
index d74bceaa4cbc893669e686814df1c374fe4eef20..046832ef14ce136d4192e6cf7b39fb54de75c522 100644 (file)
@@ -910,6 +910,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        Disable PIN 1 of APIC timer
                        Can be useful to work around chipset bugs.
 
+       dis_ucode_ldr   [X86] Disable the microcode loader.
+
        dma_debug=off   If the kernel is compiled with DMA_API_DEBUG support,
                        this option disables the debugging code at boot.
 
@@ -1092,6 +1094,21 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        you are really sure that your UEFI does sane gc and
                        fulfills the spec otherwise your board may brick.
 
+       efi_fake_mem=   nn[KMG]@ss[KMG]:aa[,nn[KMG]@ss[KMG]:aa,..] [EFI; X86]
+                       Add arbitrary attribute to specific memory range by
+                       updating original EFI memory map.
+                       Region of memory which aa attribute is added to is
+                       from ss to ss+nn.
+                       If efi_fake_mem=2G@4G:0x10000,2G@0x10a0000000:0x10000
+                       is specified, EFI_MEMORY_MORE_RELIABLE(0x10000)
+                       attribute is added to range 0x100000000-0x180000000 and
+                       0x10a0000000-0x1120000000.
+
+                       Using this parameter you can do debugging of EFI memmap
+                       related feature. For example, you can do debugging of
+                       Address Range Mirroring feature even if your box
+                       doesn't support it.
+
        eisa_irq_edge=  [PARISC,HW]
                        See header of drivers/parisc/eisa.c.
 
@@ -2283,6 +2300,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        The default parameter value of '0' causes the kernel
                        not to attempt recovery of lost locks.
 
+       nfs4.layoutstats_timer =
+                       [NFSv4.2] Change the rate at which the kernel sends
+                       layoutstats to the pNFS metadata server.
+
+                       Setting this to value to 0 causes the kernel to use
+                       whatever value is the default set by the layout
+                       driver. A non-zero value sets the minimum interval
+                       in seconds between layoutstats transmissions.
+
        nfsd.nfs4_disable_idmapping=
                        [NFSv4] When set to the default of '1', the NFSv4
                        server will return only numeric uids and gids to
@@ -3063,9 +3089,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        cache-to-cache transfer latencies.
 
        rcutree.rcu_fanout_leaf= [KNL]
-                       Increase the number of CPUs assigned to each
-                       leaf rcu_node structure.  Useful for very large
-                       systems.
+                       Change the number of CPUs assigned to each
+                       leaf rcu_node structure.  Useful for very
+                       large systems, which will choose the value 64,
+                       and for NUMA systems with large remote-access
+                       latencies, which will choose a value aligned
+                       with the appropriate hardware boundaries.
 
        rcutree.jiffies_till_sched_qs= [KNL]
                        Set required age in jiffies for a
@@ -3139,22 +3168,35 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        in a given burst of a callback-flood test.
 
        rcutorture.fqs_duration= [KNL]
-                       Set duration of force_quiescent_state bursts.
+                       Set duration of force_quiescent_state bursts
+                       in microseconds.
 
        rcutorture.fqs_holdoff= [KNL]
-                       Set holdoff time within force_quiescent_state bursts.
+                       Set holdoff time within force_quiescent_state bursts
+                       in microseconds.
 
        rcutorture.fqs_stutter= [KNL]
-                       Set wait time between force_quiescent_state bursts.
+                       Set wait time between force_quiescent_state bursts
+                       in seconds.
+
+       rcutorture.gp_cond= [KNL]
+                       Use conditional/asynchronous update-side
+                       primitives, if available.
 
        rcutorture.gp_exp= [KNL]
-                       Use expedited update-side primitives.
+                       Use expedited update-side primitives, if available.
 
        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.
+                       Use normal (non-expedited) asynchronous
+                       update-side primitives, if available.
+
+       rcutorture.gp_sync= [KNL]
+                       Use normal (non-expedited) synchronous
+                       update-side primitives, if available.  If all
+                       of rcutorture.gp_cond=, rcutorture.gp_exp=,
+                       rcutorture.gp_normal=, and rcutorture.gp_sync=
+                       are zero, rcutorture acts as if is interpreted
+                       they are all non-zero.
 
        rcutorture.n_barrier_cbs= [KNL]
                        Set callbacks/threads for rcu_barrier() testing.
@@ -3181,9 +3223,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        Set time (s) between CPU-hotplug operations, or
                        zero to disable CPU-hotplug testing.
 
-       rcutorture.torture_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
@@ -3224,6 +3263,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        Test RCU's dyntick-idle handling.  See also the
                        rcutorture.shuffle_interval parameter.
 
+       rcutorture.torture_runnable= [BOOT]
+                       Start rcutorture running at boot time.
+
        rcutorture.torture_type= [KNL]
                        Specify the RCU implementation to test.
 
@@ -4082,6 +4124,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        plus one apbt timer for broadcast timer.
                        x86_intel_mid_timer=apbt_only | lapic_and_apbt
 
+       xen_512gb_limit         [KNL,X86-64,XEN]
+                       Restricts the kernel running paravirtualized under Xen
+                       to use only up to 512 GB of RAM. The reason to do so is
+                       crash analysis tools and Xen tools for doing domain
+                       save/restore/migration must be enabled to handle larger
+                       domains.
+
        xen_emul_unplug=                [HW,X86,XEN]
                        Unplug Xen emulated devices
                        Format: [unplug0,][unplug1]