summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/x86/include/asm/kexec.h11
-rw-r--r--arch/x86/kernel/crash.c28
-rw-r--r--drivers/base/cpu.c2
-rw-r--r--drivers/base/memory.c2
-rw-r--r--include/linux/crash_core.h13
-rw-r--r--include/linux/kexec.h11
-rw-r--r--include/uapi/linux/kexec.h1
-rw-r--r--kernel/crash_core.c15
-rw-r--r--kernel/kexec.c4
-rw-r--r--kernel/kexec_file.c5
10 files changed, 48 insertions, 44 deletions
diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
index cb1320ebbc23..ae5482a2f0ca 100644
--- a/arch/x86/include/asm/kexec.h
+++ b/arch/x86/include/asm/kexec.h
@@ -210,15 +210,8 @@ extern void kdump_nmi_shootdown_cpus(void);
void arch_crash_handle_hotplug_event(struct kimage *image, void *arg);
#define arch_crash_handle_hotplug_event arch_crash_handle_hotplug_event
-#ifdef CONFIG_HOTPLUG_CPU
-int arch_crash_hotplug_cpu_support(void);
-#define crash_hotplug_cpu_support arch_crash_hotplug_cpu_support
-#endif
-
-#ifdef CONFIG_MEMORY_HOTPLUG
-int arch_crash_hotplug_memory_support(void);
-#define crash_hotplug_memory_support arch_crash_hotplug_memory_support
-#endif
+int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags);
+#define arch_crash_hotplug_support arch_crash_hotplug_support
unsigned int arch_crash_get_elfcorehdr_size(void);
#define crash_get_elfcorehdr_size arch_crash_get_elfcorehdr_size
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index 2a682fe86352..f06501445cd9 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -402,20 +402,26 @@ int crash_load_segments(struct kimage *image)
#undef pr_fmt
#define pr_fmt(fmt) "crash hp: " fmt
-/* These functions provide the value for the sysfs crash_hotplug nodes */
-#ifdef CONFIG_HOTPLUG_CPU
-int arch_crash_hotplug_cpu_support(void)
+int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags)
{
- return crash_check_update_elfcorehdr();
-}
-#endif
-#ifdef CONFIG_MEMORY_HOTPLUG
-int arch_crash_hotplug_memory_support(void)
-{
- return crash_check_update_elfcorehdr();
-}
+#ifdef CONFIG_KEXEC_FILE
+ if (image->file_mode)
+ return 1;
#endif
+ /*
+ * Initially, crash hotplug support for kexec_load was added
+ * with the KEXEC_UPDATE_ELFCOREHDR flag. Later, this
+ * functionality was expanded to accommodate multiple kexec
+ * segment updates, leading to the introduction of the
+ * KEXEC_CRASH_HOTPLUG_SUPPORT kexec flag bit. Consequently,
+ * when the kexec tool sends either of these flags, it indicates
+ * that the required kexec segment (elfcorehdr) is excluded from
+ * the SHA calculation.
+ */
+ return (kexec_flags & KEXEC_UPDATE_ELFCOREHDR ||
+ kexec_flags & KEXEC_CRASH_HOTPLUG_SUPPORT);
+}
unsigned int arch_crash_get_elfcorehdr_size(void)
{
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 56fba44ba391..c61ecb0c2ae2 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -306,7 +306,7 @@ static ssize_t crash_hotplug_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- return sysfs_emit(buf, "%d\n", crash_hotplug_cpu_support());
+ return sysfs_emit(buf, "%d\n", crash_check_hotplug_support());
}
static DEVICE_ATTR_ADMIN_RO(crash_hotplug);
#endif
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index c0436f46cfb7..67858eeb92ed 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -535,7 +535,7 @@ static DEVICE_ATTR_RW(auto_online_blocks);
static ssize_t crash_hotplug_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- return sysfs_emit(buf, "%d\n", crash_hotplug_memory_support());
+ return sysfs_emit(buf, "%d\n", crash_check_hotplug_support());
}
static DEVICE_ATTR_RO(crash_hotplug);
#endif
diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h
index 647e928efee8..44305336314e 100644
--- a/include/linux/crash_core.h
+++ b/include/linux/crash_core.h
@@ -40,14 +40,13 @@ static inline void arch_kexec_unprotect_crashkres(void) { }
static inline void arch_crash_handle_hotplug_event(struct kimage *image, void *arg) { }
#endif
-int crash_check_update_elfcorehdr(void);
+int crash_check_hotplug_support(void);
-#ifndef crash_hotplug_cpu_support
-static inline int crash_hotplug_cpu_support(void) { return 0; }
-#endif
-
-#ifndef crash_hotplug_memory_support
-static inline int crash_hotplug_memory_support(void) { return 0; }
+#ifndef arch_crash_hotplug_support
+static inline int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags)
+{
+ return 0;
+}
#endif
#ifndef crash_get_elfcorehdr_size
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 060835bb82d5..5b93a5767413 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -319,8 +319,10 @@ struct kimage {
/* If set, we are using file mode kexec syscall */
unsigned int file_mode:1;
#ifdef CONFIG_CRASH_HOTPLUG
- /* If set, allow changes to elfcorehdr of kexec_load'd image */
- unsigned int update_elfcorehdr:1;
+ /* If set, it is safe to update kexec segments that are
+ * excluded from SHA calculation.
+ */
+ unsigned int hotplug_support:1;
#endif
#ifdef ARCH_HAS_KIMAGE_ARCH
@@ -391,9 +393,10 @@ bool kexec_load_permitted(int kexec_image_type);
/* List of defined/legal kexec flags */
#ifndef CONFIG_KEXEC_JUMP
-#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_UPDATE_ELFCOREHDR)
+#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_UPDATE_ELFCOREHDR | KEXEC_CRASH_HOTPLUG_SUPPORT)
#else
-#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT | KEXEC_UPDATE_ELFCOREHDR)
+#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT | KEXEC_UPDATE_ELFCOREHDR | \
+ KEXEC_CRASH_HOTPLUG_SUPPORT)
#endif
/* List of defined/legal kexec file flags */
diff --git a/include/uapi/linux/kexec.h b/include/uapi/linux/kexec.h
index c17bb096ea68..5ae1741ea8ea 100644
--- a/include/uapi/linux/kexec.h
+++ b/include/uapi/linux/kexec.h
@@ -13,6 +13,7 @@
#define KEXEC_ON_CRASH 0x00000001
#define KEXEC_PRESERVE_CONTEXT 0x00000002
#define KEXEC_UPDATE_ELFCOREHDR 0x00000004
+#define KEXEC_CRASH_HOTPLUG_SUPPORT 0x00000008
#define KEXEC_ARCH_MASK 0xffff0000
/*
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 70fa8111a9d6..394db3ebe835 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -493,10 +493,10 @@ static DEFINE_MUTEX(__crash_hotplug_lock);
/*
* This routine utilized when the crash_hotplug sysfs node is read.
- * It reflects the kernel's ability/permission to update the crash
- * elfcorehdr directly.
+ * It reflects the kernel's ability/permission to update the kdump
+ * image directly.
*/
-int crash_check_update_elfcorehdr(void)
+int crash_check_hotplug_support(void)
{
int rc = 0;
@@ -508,10 +508,7 @@ int crash_check_update_elfcorehdr(void)
return 0;
}
if (kexec_crash_image) {
- if (kexec_crash_image->file_mode)
- rc = 1;
- else
- rc = kexec_crash_image->update_elfcorehdr;
+ rc = kexec_crash_image->hotplug_support;
}
/* Release lock now that update complete */
kexec_unlock();
@@ -552,8 +549,8 @@ static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu,
image = kexec_crash_image;
- /* Check that updating elfcorehdr is permitted */
- if (!(image->file_mode || image->update_elfcorehdr))
+ /* Check that kexec segments update is permitted */
+ if (!image->hotplug_support)
goto out;
if (hp_action == KEXEC_CRASH_HP_ADD_CPU ||
diff --git a/kernel/kexec.c b/kernel/kexec.c
index bab542fc1463..a6b3f96bb50c 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -135,8 +135,8 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
image->preserve_context = 1;
#ifdef CONFIG_CRASH_HOTPLUG
- if (flags & KEXEC_UPDATE_ELFCOREHDR)
- image->update_elfcorehdr = 1;
+ if ((flags & KEXEC_ON_CRASH) && arch_crash_hotplug_support(image, flags))
+ image->hotplug_support = 1;
#endif
ret = machine_kexec_prepare(image);
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 2d1db05fbf04..3d64290d24c9 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -376,6 +376,11 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
if (ret)
goto out;
+#ifdef CONFIG_CRASH_HOTPLUG
+ if ((flags & KEXEC_FILE_ON_CRASH) && arch_crash_hotplug_support(image, flags))
+ image->hotplug_support = 1;
+#endif
+
ret = machine_kexec_prepare(image);
if (ret)
goto out;
generated by cgit (git 2.34.1) at 2025-05-10 02:52:39 +0000