on: enable for both 32- and 64-bit processes
off: disable for both 32- and 64-bit processes
- amd_iommu= [HW,X86-84]
+ amd_iommu= [HW,X86-64]
Pass parameters to the AMD IOMMU driver in the system.
Possible values are:
fullflush - enable flushing of IO/TLB entries when
Also note the kernel might malfunction if you disable
some critical bits.
+ cma=nn[MG] [ARM,KNL]
+ Sets the size of kernel global memory area for contiguous
+ memory allocations. For more information, see
+ include/linux/dma-contiguous.h
+
cmo_free_hint= [PPC] Format: { yes | no }
Specify whether pages are marked as being inactive
when they are freed. This is used in CMO environments
a hypervisor.
Default: yes
+ coherent_pool=nn[KMG] [ARM,KNL]
+ Sets the size of memory pool for coherent, atomic dma
+ allocations, by default set to 256K.
+
code_bytes [X86] How many bytes of object code to print
in an oops report.
Range: 0 - 8192
UART at the specified I/O port or MMIO address,
switching to the matching ttyS device later. The
options are the same as for ttyS, above.
+ hvc<n> Use the hypervisor console device <n>. This is for
+ both Xen and PowerPC hypervisors.
If the device connected to the port is not a TTY but a braille
device, prepend "brl," before the device type, for instance
no_debug_objects
[KNL] Disable object debugging
+ debug_guardpage_minorder=
+ [KNL] When CONFIG_DEBUG_PAGEALLOC is set, this
+ parameter allows control of the order of pages that will
+ be intentionally kept free (and hence protected) by the
+ buddy allocator. Bigger value increase the probability
+ of catching random memory corruption, but reduce the
+ amount of memory for normal system use. The maximum
+ possible value is MAX_ORDER/2. Setting this parameter
+ to 1 or 2 should be enough to identify most random
+ memory corruption problems caused by bugs in kernel or
+ driver code when a CPU writes to (or reads from) a
+ random memory location. Note that there exists a class
+ of memory corruptions problems caused by buggy H/W or
+ F/W or by drivers badly programing DMA (basically when
+ memory is written at bus level and the CPU MMU is
+ bypassed) which are not detectable by
+ CONFIG_DEBUG_PAGEALLOC, hence this option will not help
+ tracking down these problems.
+
debugpat [X86] Enable PAT debugging
decnet.addr= [HW,NET]
earlyprintk= [X86,SH,BLACKFIN]
earlyprintk=vga
+ earlyprintk=xen
earlyprintk=serial[,ttySn[,baudrate]]
earlyprintk=ttySn[,baudrate]
earlyprintk=dbgp[debugController#]
The VGA output is eventually overwritten by the real
console.
+ The xen output can only be used by Xen PV guests.
+
ekgdboc= [X86,KGDB] Allow early kernel console debugging
ekgdboc=kbd
edd= [EDD]
Format: {"off" | "on" | "skip[mbr]"}
+ 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
+ you are really sure that your UEFI does sane gc and
+ fulfills the spec otherwise your board may brick.
+
eisa_irq_edge= [PARISC,HW]
See header of drivers/parisc/eisa.c.
i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
capability is set.
+ i915.invert_brightness=
+ [DRM] Invert the sense of the variable that is used to
+ set the brightness of the panel backlight. Normally a
+ brightness value of 0 indicates backlight switched off,
+ and the maximum of the brightness value sets the backlight
+ to maximum brightness. If this parameter is set to 0
+ (default) and the machine requires it, or this parameter
+ is set to 1, a brightness value of 0 sets the backlight
+ to maximum brightness, and the maximum of the brightness
+ value switches the backlight off.
+ -1 -- never invert brightness
+ 0 -- machine default
+ 1 -- force brightness inversion
+
icn= [HW,ISDN]
Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
* dump_id: dump IDENTIFY data.
+ * disable: Disable this device.
+
If there are multiple matching configurations changing
the same attribute, the last one is used.