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 f0c950598582f7ddc2810b1cba406465318e2ea1..046832ef14ce136d4192e6cf7b39fb54de75c522 100644 (file)
@@ -1094,6 +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.
 
@@ -3074,9 +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
@@ -4106,6 +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]