On 22/04/25 08:06, Ben Collins wrote:
Certain versions of kexec don't even work without kernel-end being
added to the device-tree. Add it even if crash-kernel is disabled.
Signed-off-by: Ben Collins <bcoll...@kernel.org>
Cc: Madhavan Srinivasan <ma...@linux.ibm.com>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-ker...@vger.kernel.org
---
arch/powerpc/kexec/core.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/kexec/core.c b/arch/powerpc/kexec/core.c
index 00e9c267b912f..7b5958c37f702 100644
--- a/arch/powerpc/kexec/core.c
+++ b/arch/powerpc/kexec/core.c
@@ -22,6 +22,8 @@
#include <asm/setup.h>
#include <asm/firmware.h>
+#define cpu_to_be_ulong __PASTE(cpu_to_be, BITS_PER_LONG)
+
#ifdef CONFIG_CRASH_DUMP
void machine_crash_shutdown(struct pt_regs *regs)
{
@@ -136,17 +138,10 @@ int __init overlaps_crashkernel(unsigned long start,
unsigned long size)
}
/* Values we need to export to the second kernel via the device tree. */
-static phys_addr_t kernel_end;
static phys_addr_t crashk_base;
static phys_addr_t crashk_size;
static unsigned long long mem_limit;
-static struct property kernel_end_prop = {
- .name = "linux,kernel-end",
- .length = sizeof(phys_addr_t),
- .value = &kernel_end,
-};
-
static struct property crashk_base_prop = {
.name = "linux,crashkernel-base",
.length = sizeof(phys_addr_t),
@@ -165,8 +160,6 @@ static struct property memory_limit_prop = {
.value = &mem_limit,
};
-#define cpu_to_be_ulong __PASTE(cpu_to_be, BITS_PER_LONG)
-
static void __init export_crashk_values(struct device_node *node)
{
/* There might be existing crash kernel properties, but we can't
@@ -190,6 +183,15 @@ static void __init export_crashk_values(struct device_node
*node)
mem_limit = cpu_to_be_ulong(memory_limit);
of_update_property(node, &memory_limit_prop);
}
+#endif /* CONFIG_CRASH_RESERVE */
+
+static phys_addr_t kernel_end;
+
+static struct property kernel_end_prop = {
+ .name = "linux,kernel-end",
+ .length = sizeof(phys_addr_t),
+ .value = &kernel_end,
+};
static int __init kexec_setup(void)
{
@@ -200,16 +202,17 @@ static int __init kexec_setup(void)
return -ENOENT;
/* remove any stale properties so ours can be found */
- of_remove_property(node, of_find_property(node, kernel_end_prop.name,
NULL));
+ of_remove_property(node, of_find_property(node, kernel_end_prop.name,
+ NULL));
/* information needed by userspace when using default_machine_kexec */
kernel_end = cpu_to_be_ulong(__pa(_end));
of_add_property(node, &kernel_end_prop);
+#ifdef CONFIG_CRASH_RESERVE
export_crashk_values(node);
-
+#endif
of_node_put(node);
return 0;
}
late_initcall(kexec_setup);
-#endif /* CONFIG_CRASH_RESERVE */
While cleaning up KEXEC and KDUMP configs, the export linux,kernel-end
was moved under CONFIG_CRASH_DUMP.
commit 5c4233cc0920cc90787aafe950b90f6c57a35b88 (HEAD, tag: powerpc-6.9-2)
Author: Hari Bathini <hbath...@linux.ibm.com>
Date: Mon Feb 26 16:00:10 2024 +0530
powerpc/kdump: Split KEXEC_CORE and CRASH_DUMP dependency
So, if kexec is enabled without CONFIG_CRASH_DUMP, the kexec command
fails to load the kexec kernel using the `kexec_load` system call.
[root]# kexec --initrd=/boot/initramfs-`uname -r`.img
/boot/vmlinuz-`uname -r` --append="`cat /proc/cmdline`" -lcd
Try gzip decompression.
Try LZMA decompression.
kernel: 0x7fffaef30010 kernel_size: 0x2ccba80
0000000000000000-0000000030000000 : 0
0000000030000000-0000004000000000 : 0
get base memory ranges:2
/proc/device-tree/chosen/linux,kernel-end: No such file or directory
Could not get memory layout
[root]# echo $?
255
So, it is better to call kexec_setup/kexec/core.c even when
CONFIG_CRASH_DUMP is not enabled and export linux,kernel-end, because kexec
requires this to load the kexec kernel using the kexec_file_load system
call.
I suggest adding a Fixes tag to the commit I mentioned above and also
including the logs I shared. That might help others discover
this fix if they run into the same issue.
Rest look good to me.
Reviewed-by: Sourabh Jain <sourabhj...@linux.ibm.com>
