+ if (ret) {
+ pr_err("Failed to remove hot-unplugged from crash memory ranges.\n");
+ return;
+ }
+ }
+
+ ret = crash_prepare_elf64_headers(cmem, false, &elfbuf, &elfsz);
+ if (ret) {
+ pr_err("Failed to prepare elf header\n");
+ return;
+ }
+
+ /*
+ * It is unlikely that kernel hit this because elfcorehdr kexec
+ * segment (memsz) is built with addition space to accommodate growing
+ * number of crash memory ranges while loading the kdump kernel. It is
+ * Just to avoid any unforeseen case.
+ */
+ if (elfsz > memsz) {
+ pr_err("Updated crash elfcorehdr elfsz %lu > memsz %lu", elfsz, memsz);
+ goto out;
+ }
+
+ ptr = __va(mem);
+ if (ptr) {
+ /* Temporarily invalidate the crash image while it is replaced */
+ xchg(&kexec_crash_image, NULL);
+
+ /* Replace the old elfcorehdr with newly prepared elfcorehdr */
+ memcpy((void *)ptr, elfbuf, elfsz);
+
+ /* The crash image is now valid once again */
+ xchg(&kexec_crash_image, image);
+ }
+out:
+ vfree(elfbuf);
+}
+
/**
* arch_crash_handle_hotplug_event - Handle crash CPU/Memory hotplug events to update the
* necessary kexec segments based on the hotplug event.
@@ -572,7 +683,7 @@ int arch_crash_hotplug_cpu_support(struct kimage *image)
* CPU addition: Update the FDT segment to include the newly added CPU.
* CPU removal: No action is needed, with the assumption that it's okay to have offline CPUs
* as part of the FDT.
- * Memory addition/removal: No action is taken as this is not yet supported.
+ * Memory addition/removal: Recreate the elfcorehdr segment
*/
void arch_crash_handle_hotplug_event(struct kimage *image, void *arg)
{
@@ -593,7 +704,6 @@ void arch_crash_handle_hotplug_event(struct kimage *image, void *arg)
return;
} else if (hp_action == KEXEC_CRASH_HP_ADD_CPU) {
-
void *fdt, *ptr;
unsigned long mem;
int i, fdt_index = -1;
@@ -628,8 +738,10 @@ void arch_crash_handle_hotplug_event(struct kimage *image, void *arg)
} else if (hp_action == KEXEC_CRASH_HP_REMOVE_MEMORY ||
hp_action == KEXEC_CRASH_HP_ADD_MEMORY) {
- pr_info_once("Crash update is not supported for memory hotplug\n");
- return;
+ struct memory_notify *mn;
+
+ mn = (struct memory_notify *)arg;
+ update_crash_elfcorehdr(image, mn);
}
}
#endif
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index e2148a009701..2457d7ec2075 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -21,6 +21,8 @@
#include <linux/memblock.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
+#include <linux/elf.h>
+
#include <asm/setup.h>
#include <asm/cputhreads.h>
#include <asm/drmem.h>
@@ -740,7 +742,35 @@ static int load_elfcorehdr_segment(struct kimage *image, struct kexec_buf *kbuf)
kbuf->buffer = headers;
kbuf->mem = KEXEC_BUF_MEM_UNKNOWN;
- kbuf->bufsz = kbuf->memsz = headers_sz;
+ kbuf->bufsz = headers_sz;
+#if defined(CONFIG_CRASH_HOTPLUG) && defined(CONFIG_MEMORY_HOTPLUG)
+ /* Adjust the elfcorehdr segment size to accommodate
+ * future crash memory ranges.
+ */
+ int max_lmb;
+ unsigned long pnum;
+
+ /* In the worst case, a Phdr is needed for every other LMB to be
+ * represented as an individual crash range.
+ */
+ max_lmb = memory_hotplug_max() / (2 * drmem_lmb_size());
+
+ /* Do not cross the Phdr max limit of the elf header.
+ * Avoid counting Phdr for crash ranges (cmem->nr_ranges)
+ * which are already part of elfcorehdr.
+ */
+ if (max_lmb > PN_XNUM)
+ pnum = PN_XNUM - cmem->nr_ranges;
+ else
+ pnum = max_lmb - cmem->nr_ranges;
+
+ /* Additional buffer space for elfcorehdr to accommodate
+ * future memory ranges.
+ */
+ kbuf->memsz = headers_sz + pnum * sizeof(Elf64_Phdr);
+#else
+ kbuf->memsz = headers_sz;
+#endif
kbuf->top_down = false;
ret = kexec_add_buffer(kbuf);
@@ -750,7 +780,7 @@ static int load_elfcorehdr_segment(struct kimage *image, struct kexec_buf *kbuf)
}
image->elf_load_addr = kbuf->mem;
- image->elf_headers_sz = headers_sz;
+ image->elf_headers_sz = kbuf->memsz;
image->elf_headers = headers;
out:
kfree(cmem);
diff --git a/arch/powerpc/kexec/ranges.c b/arch/powerpc/kexec/ranges.c
index fb3e12f15214..4fd0c5d5607b 100644
--- a/arch/powerpc/kexec/ranges.c
+++ b/arch/powerpc/kexec/ranges.c
@@ -234,6 +234,91 @@ int add_mem_range(struct crash_mem **mem_ranges, u64 base, u64 size)
return __add_mem_range(mem_ranges, base, size);
}
+/**
+ * remove_mem_range - Removes the given memory range from the range list.
+ * @mem_ranges: Range list to remove the memory range to.
+ * @base: Base address of the range to remove.
+ * @size: Size of the memory range to remove.
+ *
+ * (Re)allocates memory, if needed.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int remove_mem_range(struct crash_mem **mem_ranges, u64 base, u64 size)
+{
+ u64 end;
+ int ret = 0;
+ unsigned int i;
+ u64 mstart, mend;
+ struct crash_mem *mem_rngs = *mem_ranges;
+
+ if (!size)
+ return 0;
+
+ /*
+ * Memory range are stored as start and end address, use
+ * the same format to do remove operation.
+ */
+ end = base + size - 1;
+
+ for (i = 0; i < mem_rngs->nr_ranges; i++) {
+ mstart = mem_rngs->ranges[i].start;
+ mend = mem_rngs->ranges[i].end;
+
+ /*
+ * Memory range to remove is not part of this range entry
+ * in the memory range list
+ */
+ if (!(base >= mstart && end <= mend))
+ continue;
+
+ /*
+ * Memory range to remove is equivalent to this entry in the
+ * memory range list. Remove the range entry from the list.
+ */
+ if (base == mstart && end == mend) {
+ for (; i < mem_rngs->nr_ranges - 1; i++) {
+ mem_rngs->ranges[i].start = mem_rngs->ranges[i+1].start;
+ mem_rngs->ranges[i].end = mem_rngs->ranges[i+1].end;
+ }
+ mem_rngs->nr_ranges--;
+ goto out;
+ }
+ /*
+ * Start address of the memory range to remove and the
+ * current memory range entry in the list is same. Just
+ * move the start address of the current memory range
+ * entry in the list to end + 1.
+ */
+ else if (base == mstart) {
+ mem_rngs->ranges[i].start = end + 1;
+ goto out;
+ }
+ /*
+ * End address of the memory range to remove and the
+ * current memory range entry in the list is same.
+ * Just move the end address of the current memory
+ * range entry in the list to base - 1.
+ */
+ else if (end == mend) {
+ mem_rngs->ranges[i].end = base - 1;
+ goto out;
+ }
+ /*
+ * Memory range to remove is not at the edge of current
+ * memory range entry. Split the current memory entry into
+ * two half.
+ */
+ else {
+ mem_rngs->ranges[i].end = base - 1;
+ size = mem_rngs->ranges[i].end - end;
+ ret = add_mem_range(mem_ranges, end + 1, size);
+ }
+ }
+out:
+ return ret;
+}
+
/**
* add_tce_mem_ranges - Adds tce-table range to the given memory ranges list.
* @mem_ranges: Range list to add the memory range(s) to.
--
2.41.0
