diff options
Diffstat (limited to 'Documentation/admin-guide/kdump')
| -rw-r--r-- | Documentation/admin-guide/kdump/kdump.rst | 21 | ||||
| -rw-r--r-- | Documentation/admin-guide/kdump/vmcoreinfo.rst | 8 |
2 files changed, 25 insertions, 4 deletions
diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst index 20fabdf6567e..9c6cd52f69cf 100644 --- a/Documentation/admin-guide/kdump/kdump.rst +++ b/Documentation/admin-guide/kdump/kdump.rst @@ -311,6 +311,27 @@ crashkernel syntax crashkernel=0,low +4) crashkernel=size,cma + + Reserve additional crash kernel memory from CMA. This reservation is + usable by the first system's userspace memory and kernel movable + allocations (memory balloon, zswap). Pages allocated from this memory + range will not be included in the vmcore so this should not be used if + dumping of userspace memory is intended and it has to be expected that + some movable kernel pages may be missing from the dump. + + A standard crashkernel reservation, as described above, is still needed + to hold the crash kernel and initrd. + + This option increases the risk of a kdump failure: DMA transfers + configured by the first kernel may end up corrupting the second + kernel's memory. + + This reservation method is intended for systems that can't afford to + sacrifice enough memory for standard crashkernel reservation and where + less reliable and possibly incomplete kdump is preferable to no kdump at + all. + Boot into System Kernel ----------------------- 1) Update the boot loader (such as grub, yaboot, or lilo) configuration diff --git a/Documentation/admin-guide/kdump/vmcoreinfo.rst b/Documentation/admin-guide/kdump/vmcoreinfo.rst index 8cf4614385b7..404a15f6782c 100644 --- a/Documentation/admin-guide/kdump/vmcoreinfo.rst +++ b/Documentation/admin-guide/kdump/vmcoreinfo.rst @@ -325,14 +325,14 @@ NR_FREE_PAGES On linux-2.6.21 or later, the number of free pages is in vm_stat[NR_FREE_PAGES]. Used to get the number of free pages. -PG_lru|PG_private|PG_swapcache|PG_swapbacked|PG_slab|PG_hwpoision|PG_head_mask|PG_hugetlb ------------------------------------------------------------------------------------------ +PG_lru|PG_private|PG_swapcache|PG_swapbacked|PG_hwpoison|PG_head_mask +-------------------------------------------------------------------------- Page attributes. These flags are used to filter various unnecessary for dumping pages. -PAGE_BUDDY_MAPCOUNT_VALUE(~PG_buddy)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_offline)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_unaccepted) -------------------------------------------------------------------------------------------------------------------------- +PAGE_SLAB_MAPCOUNT_VALUE|PAGE_BUDDY_MAPCOUNT_VALUE|PAGE_OFFLINE_MAPCOUNT_VALUE|PAGE_HUGETLB_MAPCOUNT_VALUE|PAGE_UNACCEPTED_MAPCOUNT_VALUE +------------------------------------------------------------------------------------------------------------------------------------------ More page attributes. These flags are used to filter various unnecessary for dumping pages. |