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authorLinus Torvalds <torvalds@linux-foundation.org>2024-09-21 08:20:50 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2024-09-21 08:20:50 -0700
commit7856a565416e0cf091f825b0e25c7a1b7abb650e (patch)
tree0a04a0594167fc997b3b1299610b5ef95ab89f19 /kernel/crash_core.c
parentMerge tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm (diff)
parentlist: test: increase coverage of list_test_list_replace*() (diff)
downloadwireguard-linux-7856a565416e0cf091f825b0e25c7a1b7abb650e.tar.xz
wireguard-linux-7856a565416e0cf091f825b0e25c7a1b7abb650e.zip
Merge tag 'mm-nonmm-stable-2024-09-21-07-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton: "Many singleton patches - please see the various changelogs for details. Quite a lot of nilfs2 work this time around. Notable patch series in this pull request are: - "mul_u64_u64_div_u64: new implementation" by Nicolas Pitre, with assistance from Uwe Kleine-König. Reimplement mul_u64_u64_div_u64() to provide (much) more accurate results. The current implementation was causing Uwe some issues in the PWM drivers. - "xz: Updates to license, filters, and compression options" from Lasse Collin. Miscellaneous maintenance and kinor feature work to the xz decompressor. - "Fix some GDB command error and add some GDB commands" from Kuan-Ying Lee. Fixes and enhancements to the gdb scripts. - "treewide: add missing MODULE_DESCRIPTION() macros" from Jeff Johnson. Adds lots of MODULE_DESCRIPTIONs, thus fixing lots of warnings about this. - "nilfs2: add support for some common ioctls" from Ryusuke Konishi. Adds various commonly-available ioctls to nilfs2. - "This series fixes a number of formatting issues in kernel doc comments" from Ryusuke Konishi does that. - "nilfs2: prevent unexpected ENOENT propagation" from Ryusuke Konishi. Fix issues where -ENOENT was being unintentionally and inappropriately returned to userspace. - "nilfs2: assorted cleanups" from Huang Xiaojia. - "nilfs2: fix potential issues with empty b-tree nodes" from Ryusuke Konishi fixes some issues which can occur on corrupted nilfs2 filesystems. - "scripts/decode_stacktrace.sh: improve error reporting and usability" from Luca Ceresoli does those things" * tag 'mm-nonmm-stable-2024-09-21-07-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (103 commits) list: test: increase coverage of list_test_list_replace*() list: test: fix tests for list_cut_position() proc: use __auto_type more treewide: correct the typo 'retun' ocfs2: cleanup return value and mlog in ocfs2_global_read_info() nilfs2: remove duplicate 'unlikely()' usage nilfs2: fix potential oob read in nilfs_btree_check_delete() nilfs2: determine empty node blocks as corrupted nilfs2: fix potential null-ptr-deref in nilfs_btree_insert() user_namespace: use kmemdup_array() instead of kmemdup() for multiple allocation tools/mm: rm thp_swap_allocator_test when make clean squashfs: fix percpu address space issues in decompressor_multi_percpu.c lib: glob.c: added null check for character class nilfs2: refactor nilfs_segctor_thread() nilfs2: use kthread_create and kthread_stop for the log writer thread nilfs2: remove sc_timer_task nilfs2: do not repair reserved inode bitmap in nilfs_new_inode() nilfs2: eliminate the shared counter and spinlock for i_generation nilfs2: separate inode type information from i_state field nilfs2: use the BITS_PER_LONG macro ...
Diffstat (limited to 'kernel/crash_core.c')
-rw-r--r--kernel/crash_core.c33
1 files changed, 20 insertions, 13 deletions
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 63cf89393c6e..c1048893f4b6 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -505,7 +505,7 @@ int crash_check_hotplug_support(void)
crash_hotplug_lock();
/* Obtain lock while reading crash information */
if (!kexec_trylock()) {
- pr_info("kexec_trylock() failed, elfcorehdr may be inaccurate\n");
+ pr_info("kexec_trylock() failed, kdump image may be inaccurate\n");
crash_hotplug_unlock();
return 0;
}
@@ -520,18 +520,25 @@ int crash_check_hotplug_support(void)
}
/*
- * To accurately reflect hot un/plug changes of cpu and memory resources
- * (including onling and offlining of those resources), the elfcorehdr
- * (which is passed to the crash kernel via the elfcorehdr= parameter)
- * must be updated with the new list of CPUs and memories.
+ * To accurately reflect hot un/plug changes of CPU and Memory resources
+ * (including onling and offlining of those resources), the relevant
+ * kexec segments must be updated with latest CPU and Memory resources.
*
- * In order to make changes to elfcorehdr, two conditions are needed:
- * First, the segment containing the elfcorehdr must be large enough
- * to permit a growing number of resources; the elfcorehdr memory size
- * is based on NR_CPUS_DEFAULT and CRASH_MAX_MEMORY_RANGES.
- * Second, purgatory must explicitly exclude the elfcorehdr from the
- * list of segments it checks (since the elfcorehdr changes and thus
- * would require an update to purgatory itself to update the digest).
+ * Architectures must ensure two things for all segments that need
+ * updating during hotplug events:
+ *
+ * 1. Segments must be large enough to accommodate a growing number of
+ * resources.
+ * 2. Exclude the segments from SHA verification.
+ *
+ * For example, on most architectures, the elfcorehdr (which is passed
+ * to the crash kernel via the elfcorehdr= parameter) must include the
+ * new list of CPUs and memory. To make changes to the elfcorehdr, it
+ * should be large enough to permit a growing number of CPU and Memory
+ * resources. One can estimate the elfcorehdr memory size based on
+ * NR_CPUS_DEFAULT and CRASH_MAX_MEMORY_RANGES. The elfcorehdr is
+ * excluded from SHA verification by default if the architecture
+ * supports crash hotplug.
*/
static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu, void *arg)
{
@@ -540,7 +547,7 @@ static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu,
crash_hotplug_lock();
/* Obtain lock while changing crash information */
if (!kexec_trylock()) {
- pr_info("kexec_trylock() failed, elfcorehdr may be inaccurate\n");
+ pr_info("kexec_trylock() failed, kdump image may be inaccurate\n");
crash_hotplug_unlock();
return;
}