diff options
Diffstat (limited to 'Documentation/admin-guide/kernel-parameters.txt')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 58 |
1 files changed, 46 insertions, 12 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 1c0a3cf6fcc9..cb89dbdedc46 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1469,6 +1469,12 @@ Don't use this when you are not running on the android emulator + gpio-mockup.gpio_mockup_ranges + [HW] Sets the ranges of gpiochip of for this device. + Format: <start1>,<end1>,<start2>,<end2>... + gpio-mockup.gpio_mockup_named_lines + [HW] Let the driver know GPIO lines should be named. + gpt [EFI] Forces disk with valid GPT signature but invalid Protective MBR to be treated as GPT. If the primary GPT is corrupted, it enables the backup/alternate @@ -1492,10 +1498,6 @@ Format: <unsigned int> such that (rxsize & ~0x1fffc0) == 0. Default: 1024 - gpio-mockup.gpio_mockup_ranges - [HW] Sets the ranges of gpiochip of for this device. - Format: <start1>,<end1>,<start2>,<end2>... - hardlockup_all_cpu_backtrace= [KNL] Should the hard-lockup detector generate backtraces on all cpus. @@ -1833,6 +1835,18 @@ initcall functions. Useful for debugging built-in modules and initcalls. + initramfs_async= [KNL] + Format: <bool> + Default: 1 + This parameter controls whether the initramfs + image is unpacked asynchronously, concurrently + with devices being probed and + initialized. This should normally just work, + but as a debugging aid, one can get the + historical behaviour of the initramfs + unpacking being completed before device_ and + late_ initcalls. + initrd= [BOOT] Specify the location of the initial ramdisk initrdmem= [KNL] Specify a physical address and size from which to @@ -1877,13 +1891,6 @@ bypassed by not enabling DMAR with this option. In this case, gfx device will use physical address for DMA. - forcedac [X86-64] - With this option iommu will not optimize to look - for io virtual address below 32-bit forcing dual - address cycle on pci bus for cards supporting greater - than 32-bit addressing. The default is to look - for translation below 32-bit and if not available - then look in the higher range. strict [Default Off] With this option on every unmap_single operation will result in a hardware IOTLB flush operation as opposed @@ -1972,6 +1979,14 @@ nobypass [PPC/POWERNV] Disable IOMMU bypass, using IOMMU for PCI devices. + iommu.forcedac= [ARM64, X86] Control IOVA allocation for PCI devices. + Format: { "0" | "1" } + 0 - Try to allocate a 32-bit DMA address first, before + falling back to the full range if needed. + 1 - Allocate directly from the full usable range, + forcing Dual Address Cycle for PCI cards supporting + greater than 32-bit addressing. + iommu.strict= [ARM64] Configure TLB invalidation behaviour Format: { "0" | "1" } 0 - Lazy mode. @@ -2801,7 +2816,24 @@ seconds. Use this parameter to check at some other rate. 0 disables periodic checking. - memtest= [KNL,X86,ARM,PPC] Enable memtest + memory_hotplug.memmap_on_memory + [KNL,X86,ARM] Boolean flag to enable this feature. + Format: {on | off (default)} + When enabled, runtime hotplugged memory will + allocate its internal metadata (struct pages) + from the hotadded memory which will allow to + hotadd a lot of memory without requiring + additional memory to do so. + This feature is disabled by default because it + has some implication on large (e.g. GB) + allocations in some configurations (e.g. small + memory blocks). + The state of the flag can be read in + /sys/module/memory_hotplug/parameters/memmap_on_memory. + Note that even when enabled, there are a few cases where + the feature is not effective. + + memtest= [KNL,X86,ARM,PPC,RISCV] Enable memtest Format: <integer> default : 0 <disable> Specifies the number of memtest passes to be @@ -3250,6 +3282,8 @@ nohugeiomap [KNL,X86,PPC,ARM64] Disable kernel huge I/O mappings. + nohugevmalloc [PPC] Disable kernel huge vmalloc mappings. + nosmt [KNL,S390] Disable symmetric multithreading (SMT). Equivalent to smt=1. |