From: Sasha Levin <sashal@kernel.org>
To: stable@vger.kernel.org
Cc: Hari Bathini <hbathini@linux.ibm.com>,
Michael Ellerman <mpe@ellerman.id.au>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 6.6.y 1/3] powerpc/kexec: split CONFIG_KEXEC_FILE and CONFIG_CRASH_DUMP
Date: Thu, 10 Sep 2026 21:12:54 -0400 [thread overview]
Message-ID: <20260911011256.4032346-1-sashal@kernel.org> (raw)
In-Reply-To: <2026090924-deskwork-unvocal-d17e@gregkh>
From: Hari Bathini <hbathini@linux.ibm.com>
[ Upstream commit 33f2cc0a2e90f7177c49559b434191b02efd0cd5 ]
CONFIG_KEXEC_FILE does not have to select CONFIG_CRASH_DUMP. Move
some code under CONFIG_CRASH_DUMP to support CONFIG_KEXEC_FILE and
!CONFIG_CRASH_DUMP case.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240226103010.589537-3-hbathini@linux.ibm.com
Stable-dep-of: fa40f9dbdd4a ("powerpc/kexec_file: Prevent kexec range truncation")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/kexec/elf_64.c | 4 +-
arch/powerpc/kexec/file_load_64.c | 269 ++++++++++++++++--------------
2 files changed, 142 insertions(+), 131 deletions(-)
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index eeb258002d1e0..89315dd7399e6 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c
@@ -47,7 +47,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
if (ret)
return ERR_PTR(ret);
- if (image->type == KEXEC_TYPE_CRASH) {
+ if (IS_ENABLED(CONFIG_CRASH_DUMP) && image->type == KEXEC_TYPE_CRASH) {
/* min & max buffer values for kdump case */
kbuf.buf_min = pbuf.buf_min = crashk_res.start;
kbuf.buf_max = pbuf.buf_max =
@@ -70,7 +70,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem);
/* Load additional segments needed for panic kernel */
- if (image->type == KEXEC_TYPE_CRASH) {
+ if (IS_ENABLED(CONFIG_CRASH_DUMP) && image->type == KEXEC_TYPE_CRASH) {
ret = load_crashdump_segments_ppc64(image, &kbuf);
if (ret) {
pr_err("Failed to load kdump kernel segments\n");
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index 12cbfc9fce451..c66773bfad695 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -96,119 +96,6 @@ static int get_exclude_memory_ranges(struct crash_mem **mem_ranges)
return ret;
}
-/**
- * get_usable_memory_ranges - Get usable memory ranges. This list includes
- * regions like crashkernel, opal/rtas & tce-table,
- * that kdump kernel could use.
- * @mem_ranges: Range list to add the memory ranges to.
- *
- * Returns 0 on success, negative errno on error.
- */
-static int get_usable_memory_ranges(struct crash_mem **mem_ranges)
-{
- int ret;
-
- /*
- * Early boot failure observed on guests when low memory (first memory
- * block?) is not added to usable memory. So, add [0, crashk_res.end]
- * instead of [crashk_res.start, crashk_res.end] to workaround it.
- * Also, crashed kernel's memory must be added to reserve map to
- * avoid kdump kernel from using it.
- */
- ret = add_mem_range(mem_ranges, 0, crashk_res.end + 1);
- if (ret)
- goto out;
-
- ret = add_rtas_mem_range(mem_ranges);
- if (ret)
- goto out;
-
- ret = add_opal_mem_range(mem_ranges);
- if (ret)
- goto out;
-
- ret = add_tce_mem_ranges(mem_ranges);
-out:
- if (ret)
- pr_err("Failed to setup usable memory ranges\n");
- return ret;
-}
-
-/**
- * get_crash_memory_ranges - Get crash memory ranges. This list includes
- * first/crashing kernel's memory regions that
- * would be exported via an elfcore.
- * @mem_ranges: Range list to add the memory ranges to.
- *
- * Returns 0 on success, negative errno on error.
- */
-static int get_crash_memory_ranges(struct crash_mem **mem_ranges)
-{
- phys_addr_t base, end;
- struct crash_mem *tmem;
- u64 i;
- int ret;
-
- for_each_mem_range(i, &base, &end) {
- u64 size = end - base;
-
- /* Skip backup memory region, which needs a separate entry */
- if (base == BACKUP_SRC_START) {
- if (size > BACKUP_SRC_SIZE) {
- base = BACKUP_SRC_END + 1;
- size -= BACKUP_SRC_SIZE;
- } else
- continue;
- }
-
- ret = add_mem_range(mem_ranges, base, size);
- if (ret)
- goto out;
-
- /* Try merging adjacent ranges before reallocation attempt */
- if ((*mem_ranges)->nr_ranges == (*mem_ranges)->max_nr_ranges)
- sort_memory_ranges(*mem_ranges, true);
- }
-
- /* Reallocate memory ranges if there is no space to split ranges */
- tmem = *mem_ranges;
- if (tmem && (tmem->nr_ranges == tmem->max_nr_ranges)) {
- tmem = realloc_mem_ranges(mem_ranges);
- if (!tmem)
- goto out;
- }
-
- /* Exclude crashkernel region */
- ret = crash_exclude_mem_range(tmem, crashk_res.start, crashk_res.end);
- if (ret)
- goto out;
-
- /*
- * FIXME: For now, stay in parity with kexec-tools but if RTAS/OPAL
- * regions are exported to save their context at the time of
- * crash, they should actually be backed up just like the
- * first 64K bytes of memory.
- */
- ret = add_rtas_mem_range(mem_ranges);
- if (ret)
- goto out;
-
- ret = add_opal_mem_range(mem_ranges);
- if (ret)
- goto out;
-
- /* create a separate program header for the backup region */
- ret = add_mem_range(mem_ranges, BACKUP_SRC_START, BACKUP_SRC_SIZE);
- if (ret)
- goto out;
-
- sort_memory_ranges(*mem_ranges, false);
-out:
- if (ret)
- pr_err("Failed to setup crash memory ranges\n");
- return ret;
-}
-
/**
* get_reserved_memory_ranges - Get reserve memory ranges. This list includes
* memory regions that should be added to the
@@ -434,6 +321,120 @@ static int locate_mem_hole_bottom_up_ppc64(struct kexec_buf *kbuf,
return ret;
}
+#ifdef CONFIG_CRASH_DUMP
+/**
+ * get_usable_memory_ranges - Get usable memory ranges. This list includes
+ * regions like crashkernel, opal/rtas & tce-table,
+ * that kdump kernel could use.
+ * @mem_ranges: Range list to add the memory ranges to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int get_usable_memory_ranges(struct crash_mem **mem_ranges)
+{
+ int ret;
+
+ /*
+ * Early boot failure observed on guests when low memory (first memory
+ * block?) is not added to usable memory. So, add [0, crashk_res.end]
+ * instead of [crashk_res.start, crashk_res.end] to workaround it.
+ * Also, crashed kernel's memory must be added to reserve map to
+ * avoid kdump kernel from using it.
+ */
+ ret = add_mem_range(mem_ranges, 0, crashk_res.end + 1);
+ if (ret)
+ goto out;
+
+ ret = add_rtas_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_opal_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_tce_mem_ranges(mem_ranges);
+out:
+ if (ret)
+ pr_err("Failed to setup usable memory ranges\n");
+ return ret;
+}
+
+/**
+ * get_crash_memory_ranges - Get crash memory ranges. This list includes
+ * first/crashing kernel's memory regions that
+ * would be exported via an elfcore.
+ * @mem_ranges: Range list to add the memory ranges to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int get_crash_memory_ranges(struct crash_mem **mem_ranges)
+{
+ phys_addr_t base, end;
+ struct crash_mem *tmem;
+ u64 i;
+ int ret;
+
+ for_each_mem_range(i, &base, &end) {
+ u64 size = end - base;
+
+ /* Skip backup memory region, which needs a separate entry */
+ if (base == BACKUP_SRC_START) {
+ if (size > BACKUP_SRC_SIZE) {
+ base = BACKUP_SRC_END + 1;
+ size -= BACKUP_SRC_SIZE;
+ } else
+ continue;
+ }
+
+ ret = add_mem_range(mem_ranges, base, size);
+ if (ret)
+ goto out;
+
+ /* Try merging adjacent ranges before reallocation attempt */
+ if ((*mem_ranges)->nr_ranges == (*mem_ranges)->max_nr_ranges)
+ sort_memory_ranges(*mem_ranges, true);
+ }
+
+ /* Reallocate memory ranges if there is no space to split ranges */
+ tmem = *mem_ranges;
+ if (tmem && (tmem->nr_ranges == tmem->max_nr_ranges)) {
+ tmem = realloc_mem_ranges(mem_ranges);
+ if (!tmem)
+ goto out;
+ }
+
+ /* Exclude crashkernel region */
+ ret = crash_exclude_mem_range(tmem, crashk_res.start, crashk_res.end);
+ if (ret)
+ goto out;
+
+ /*
+ * FIXME: For now, stay in parity with kexec-tools but if RTAS/OPAL
+ * regions are exported to save their context at the time of
+ * crash, they should actually be backed up just like the
+ * first 64K bytes of memory.
+ */
+ ret = add_rtas_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_opal_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ /* create a separate program header for the backup region */
+ ret = add_mem_range(mem_ranges, BACKUP_SRC_START, BACKUP_SRC_SIZE);
+ if (ret)
+ goto out;
+
+ sort_memory_ranges(*mem_ranges, false);
+out:
+ if (ret)
+ pr_err("Failed to setup crash memory ranges\n");
+ return ret;
+}
+
/**
* check_realloc_usable_mem - Reallocate buffer if it can't accommodate entries
* @um_info: Usable memory buffer and ranges info.
@@ -863,6 +864,7 @@ int load_crashdump_segments_ppc64(struct kimage *image,
return 0;
}
+#endif
/**
* setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
@@ -977,26 +979,14 @@ static unsigned int cpu_node_size(void)
return size;
}
-/**
- * kexec_extra_fdt_size_ppc64 - Return the estimated additional size needed to
- * setup FDT for kexec/kdump kernel.
- * @image: kexec image being loaded.
- *
- * Returns the estimated extra size needed for kexec/kdump kernel FDT.
- */
-unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image)
+static unsigned int kdump_extra_fdt_size_ppc64(struct kimage *image)
{
unsigned int cpu_nodes, extra_size = 0;
struct device_node *dn;
u64 usm_entries;
- // Budget some space for the password blob. There's already extra space
- // for the key name
- if (plpks_is_available())
- extra_size += (unsigned int)plpks_get_passwordlen();
-
- if (image->type != KEXEC_TYPE_CRASH)
- return extra_size;
+ if (!IS_ENABLED(CONFIG_CRASH_DUMP) || image->type != KEXEC_TYPE_CRASH)
+ return 0;
/*
* For kdump kernel, account for linux,usable-memory and
@@ -1024,6 +1014,25 @@ unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image)
return extra_size;
}
+/**
+ * kexec_extra_fdt_size_ppc64 - Return the estimated additional size needed to
+ * setup FDT for kexec/kdump kernel.
+ * @image: kexec image being loaded.
+ *
+ * Returns the estimated extra size needed for kexec/kdump kernel FDT.
+ */
+unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image)
+{
+ unsigned int extra_size = 0;
+
+ // Budget some space for the password blob. There's already extra space
+ // for the key name
+ if (plpks_is_available())
+ extra_size += (unsigned int)plpks_get_passwordlen();
+
+ return extra_size + kdump_extra_fdt_size_ppc64(image);
+}
+
/**
* add_node_props - Reads node properties from device node structure and add
* them to fdt.
@@ -1172,6 +1181,7 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
struct crash_mem *umem = NULL, *rmem = NULL;
int i, nr_ranges, ret;
+#ifdef CONFIG_CRASH_DUMP
/*
* Restrict memory usage for kdump kernel by setting up
* usable memory ranges and memory reserve map.
@@ -1208,6 +1218,7 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
goto out;
}
}
+#endif
/* Update cpus nodes information to account hotplug CPUs. */
ret = update_cpus_node(fdt);
@@ -1279,7 +1290,7 @@ int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
buf_min = kbuf->buf_min;
buf_max = kbuf->buf_max;
/* Segments for kdump kernel should be within crashkernel region */
- if (kbuf->image->type == KEXEC_TYPE_CRASH) {
+ if (IS_ENABLED(CONFIG_CRASH_DUMP) && kbuf->image->type == KEXEC_TYPE_CRASH) {
buf_min = (buf_min < crashk_res.start ?
crashk_res.start : buf_min);
buf_max = (buf_max > crashk_res.end ?
--
2.53.0
next prev parent reply other threads:[~2026-09-11 1:12 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-09 9:52 FAILED: patch "[PATCH] powerpc/kexec_file: Prevent kexec range truncation" failed to apply to 6.6-stable tree gregkh
2026-09-11 1:12 ` Sasha Levin [this message]
2026-09-11 1:12 ` [PATCH 6.6.y 2/3] powerpc/kexec: move *_memory_ranges functions to ranges.c Sasha Levin
2026-09-11 1:12 ` [PATCH 6.6.y 3/3] powerpc/kexec_file: Prevent kexec range truncation Sasha Levin
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