aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/admin-guide
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2025-05-31 19:12:53 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2025-05-31 19:12:53 -0700
commit7d4e49a77d9930c69751b9192448fda6ff9100f1 (patch)
treea041784a50f35185c77d235ba28037909c53fbd5 /Documentation/admin-guide
parentMerge tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm (diff)
parentllist: make llist_add_batch() a static inline (diff)
downloadlinux-rng-7d4e49a77d9930c69751b9192448fda6ff9100f1.tar.xz
linux-rng-7d4e49a77d9930c69751b9192448fda6ff9100f1.zip
Merge tag 'mm-nonmm-stable-2025-05-31-15-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton: - "hung_task: extend blocking task stacktrace dump to semaphore" from Lance Yang enhances the hung task detector. The detector presently dumps the blocking tasks's stack when it is blocked on a mutex. Lance's series extends this to semaphores - "nilfs2: improve sanity checks in dirty state propagation" from Wentao Liang addresses a couple of minor flaws in nilfs2 - "scripts/gdb: Fixes related to lx_per_cpu()" from Illia Ostapyshyn fixes a couple of issues in the gdb scripts - "Support kdump with LUKS encryption by reusing LUKS volume keys" from Coiby Xu addresses a usability problem with kdump. When the dump device is LUKS-encrypted, the kdump kernel may not have the keys to the encrypted filesystem. A full writeup of this is in the series [0/N] cover letter - "sysfs: add counters for lockups and stalls" from Max Kellermann adds /sys/kernel/hardlockup_count and /sys/kernel/hardlockup_count and /sys/kernel/rcu_stall_count - "fork: Page operation cleanups in the fork code" from Pasha Tatashin implements a number of code cleanups in fork.c - "scripts/gdb/symbols: determine KASLR offset on s390 during early boot" from Ilya Leoshkevich fixes some s390 issues in the gdb scripts * tag 'mm-nonmm-stable-2025-05-31-15-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (67 commits) llist: make llist_add_batch() a static inline delayacct: remove redundant code and adjust indentation squashfs: add optional full compressed block caching crash_dump, nvme: select CONFIGFS_FS as built-in scripts/gdb/symbols: determine KASLR offset on s390 during early boot scripts/gdb/symbols: factor out pagination_off() scripts/gdb/symbols: factor out get_vmlinux() kernel/panic.c: format kernel-doc comments mailmap: update and consolidate Casey Connolly's name and email nilfs2: remove wbc->for_reclaim handling fork: define a local GFP_VMAP_STACK fork: check charging success before zeroing stack fork: clean-up naming of vm_stack/vm_struct variables in vmap stacks code fork: clean-up ifdef logic around stack allocation kernel/rcu/tree_stall: add /sys/kernel/rcu_stall_count kernel/watchdog: add /sys/kernel/{hard,soft}lockup_count x86/crash: make the page that stores the dm crypt keys inaccessible x86/crash: pass dm crypt keys to kdump kernel Revert "x86/mm: Remove unused __set_memory_prot()" crash_dump: retrieve dm crypt keys in kdump kernel ...
Diffstat (limited to 'Documentation/admin-guide')
-rw-r--r--Documentation/admin-guide/kdump/kdump.rst32
-rw-r--r--Documentation/admin-guide/kdump/vmcoreinfo.rst4
2 files changed, 34 insertions, 2 deletions
diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst
index 1f7f14c6e184..20fabdf6567e 100644
--- a/Documentation/admin-guide/kdump/kdump.rst
+++ b/Documentation/admin-guide/kdump/kdump.rst
@@ -547,6 +547,38 @@ from within add_taint() whenever the value set in this bitmask matches with the
bit flag being set by add_taint().
This will cause a kdump to occur at the add_taint()->panic() call.
+Write the dump file to encrypted disk volume
+============================================
+
+CONFIG_CRASH_DM_CRYPT can be enabled to support saving the dump file to an
+encrypted disk volume (only x86_64 supported for now). User space can interact
+with /sys/kernel/config/crash_dm_crypt_keys for setup,
+
+1. Tell the first kernel what logon keys are needed to unlock the disk volumes,
+ # Add key #1
+ mkdir /sys/kernel/config/crash_dm_crypt_keys/7d26b7b4-e342-4d2d-b660-7426b0996720
+ # Add key #1's description
+ echo cryptsetup:7d26b7b4-e342-4d2d-b660-7426b0996720 > /sys/kernel/config/crash_dm_crypt_keys/description
+
+ # how many keys do we have now?
+ cat /sys/kernel/config/crash_dm_crypt_keys/count
+ 1
+
+ # Add key #2 in the same way
+
+ # how many keys do we have now?
+ cat /sys/kernel/config/crash_dm_crypt_keys/count
+ 2
+
+ # To support CPU/memory hot-plugging, re-use keys already saved to reserved
+ # memory
+ echo true > /sys/kernel/config/crash_dm_crypt_key/reuse
+
+2. Load the dump-capture kernel
+
+3. After the dump-capture kerne get booted, restore the keys to user keyring
+ echo yes > /sys/kernel/crash_dm_crypt_keys/restore
+
Contact
=======
diff --git a/Documentation/admin-guide/kdump/vmcoreinfo.rst b/Documentation/admin-guide/kdump/vmcoreinfo.rst
index 0f714fc945ac..8cf4614385b7 100644
--- a/Documentation/admin-guide/kdump/vmcoreinfo.rst
+++ b/Documentation/admin-guide/kdump/vmcoreinfo.rst
@@ -331,8 +331,8 @@ PG_lru|PG_private|PG_swapcache|PG_swapbacked|PG_slab|PG_hwpoision|PG_head_mask|P
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_BUDDY_MAPCOUNT_VALUE(~PG_buddy)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_offline)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_unaccepted)
+-------------------------------------------------------------------------------------------------------------------------
More page attributes. These flags are used to filter various unnecessary for
dumping pages.