diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index d1cc3a9fa14..8ccbf27aead 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -596,9 +596,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted. is selected automatically. Check Documentation/kdump/kdump.txt for further details. - crashkernel_low=size[KMG] - [KNL, x86] parts under 4G. - crashkernel=range1:size1[,range2:size2,...][@offset] [KNL] Same as above, but depends on the memory in the running system. The syntax of range is @@ -606,6 +603,26 @@ bytes respectively. Such letter suffixes can also be entirely omitted. a memory unit (amount[KMG]). See also Documentation/kdump/kdump.txt for an example. + crashkernel=size[KMG],high + [KNL, x86_64] 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] 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. Kernel would + try to allocate 72M below 4G automatically. + This one let user to specify own low range under 4G + for second kernel instead. + 0: to disable low allocation. + It will be ignored when crashkernel=X,high is not used + or memory reserved is below 4G. + cs89x0_dma= [HW,NET] Format: <dma> |