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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt38
1 files changed, 22 insertions, 16 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 6ee0f9a5da70..31b3a25680d0 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -888,9 +888,9 @@
memory region [offset, offset + size] for that kernel
image. If '@offset' is omitted, then a suitable offset
is selected automatically.
- [KNL, X86-64, ARM64, RISCV] Select a region under 4G first, and
- fall back to reserve region above 4G when '@offset'
- hasn't been specified.
+ [KNL, X86-64, ARM64, RISCV, LoongArch] Select a region
+ under 4G first, and fall back to reserve region above
+ 4G when '@offset' hasn't been specified.
See Documentation/admin-guide/kdump/kdump.rst for further details.
crashkernel=range1:size1[,range2:size2,...][@offset]
@@ -901,25 +901,27 @@
Documentation/admin-guide/kdump/kdump.rst for an example.
crashkernel=size[KMG],high
- [KNL, X86-64, ARM64, RISCV] range could be above 4G.
+ [KNL, X86-64, ARM64, RISCV, LoongArch] range could be
+ above 4G.
Allow kernel to allocate physical memory region from top,
so could be above 4G if system have more than 4G ram
installed. Otherwise memory region will be allocated
below 4G, if available.
It will be ignored if crashkernel=X is specified.
crashkernel=size[KMG],low
- [KNL, X86-64, ARM64, RISCV] range under 4G. When crashkernel=X,high
- is passed, kernel could allocate physical memory region
- above 4G, that cause second kernel crash on system
- that require some amount of low memory, e.g. swiotlb
- requires at least 64M+32K low memory, also enough extra
- low memory is needed to make sure DMA buffers for 32-bit
- devices won't run out. Kernel would try to allocate
+ [KNL, X86-64, ARM64, RISCV, LoongArch] range under 4G.
+ When crashkernel=X,high is passed, kernel could allocate
+ physical memory region above 4G, that cause second kernel
+ crash on system that require some amount of low memory,
+ e.g. swiotlb requires at least 64M+32K low memory, also
+ enough extra low memory is needed to make sure DMA buffers
+ for 32-bit devices won't run out. Kernel would try to allocate
default size of memory below 4G automatically. The default
size is platform dependent.
--> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB)
--> arm64: 128MiB
--> riscv: 128MiB
+ --> loongarch: 128MiB
This one lets the user specify own low range under 4G
for second kernel instead.
0: to disable low allocation.
@@ -2449,7 +2451,7 @@
between unregistering the boot console and initializing
the real console.
- keepinitrd [HW,ARM]
+ keepinitrd [HW,ARM] See retain_initrd.
kernelcore= [KNL,X86,IA-64,PPC]
Format: nn[KMGTPE] | nn% | "mirror"
@@ -3996,9 +3998,9 @@
vulnerability. System may allow data leaks with this
option.
- no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES] Disable paravirtualized
- steal time accounting. steal time is computed, but
- won't influence scheduler behaviour
+ no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES,RISCV] Disable
+ paravirtualized steal time accounting. steal time is
+ computed, but won't influence scheduler behaviour
nosync [HW,M68K] Disables sync negotiation for all devices.
@@ -5604,7 +5606,8 @@
Useful for devices that are detected asynchronously
(e.g. USB and MMC devices).
- retain_initrd [RAM] Keep initrd memory after extraction
+ retain_initrd [RAM] Keep initrd memory after extraction. After boot, it will
+ be accessible via /sys/firmware/initrd.
retbleed= [X86] Control mitigation of RETBleed (Arbitrary
Speculative Code Execution with Return Instructions)
@@ -6932,6 +6935,9 @@
pause after every control message);
o = USB_QUIRK_HUB_SLOW_RESET (Hub needs extra
delay after resetting its port);
+ p = USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT
+ (Reduce timeout of the SET_ADDRESS
+ request from 5000 ms to 500 ms);
Example: quirks=0781:5580:bk,0a5c:5834:gij
usbhid.mousepoll=