Workaround for segfault by "makedumpfile --mem-usage" on PPC64

Resolves: RHEL-41117
Upstream: Fedora
Conflict: None

Signed-off-by: Lichen Liu <lichliu@redhat.com>

0001-PATCH-Workaround-for-segfault-by-makedumpfile-mem-us.patch

@@ -0,0 +1,58 @@
+From 900190de6b67b2de410cfc8023c1b198a416ceb3 Mon Sep 17 00:00:00 2001
+From: Kazuhito Hagio <k-hagio-ab@nec.com>
+Date: Mon, 22 Jul 2024 14:31:43 +0900
+Subject: [PATCH] [PATCH] Workaround for segfault by "makedumpfile --mem-usage"
+ on PPC64
+
+"makedumpfile --mem-usage /proc/kcore" can cause a segmentation fault on
+PPC64, because the readmem() of the following code path uses cache
+before it's initialized in initial().
+
+  show_mem_usage
+    get_page_offset
+      get_versiondep_info_ppc64
+        readmem
+    ...
+    initial
+        cache_init
+
+The get_page_offset() is needed to get vmcoreinfo from /proc/kcore data,
+so we can avoid calling it when a vmcoreinfo exists in the ELF NOTE
+segment of /proc/kcore, i.e. on Linux 4.19 and later.
+
+(Note: for older kernels, we will need another way to fix it.)
+
+Reported-by: Lichen Liu <lichliu@redhat.com>
+Signed-off-by: Kazuhito Hagio <k-hagio-ab@nec.com>
+---
+ makedumpfile.c | 12 ++++++------
+ 1 file changed, 6 insertions(+), 6 deletions(-)
+
+diff --git a/makedumpfile.c b/makedumpfile.c
+index 5b34712..7d1dfcc 100644
+--- a/makedumpfile.c
++++ b/makedumpfile.c
+@@ -12019,14 +12019,14 @@ int show_mem_usage(void)
+ 		DEBUG_MSG("Read vmcoreinfo from NOTE segment: %d\n", vmcoreinfo);
+ 	}
+ 
+-	if (!get_page_offset())
+-		return FALSE;
++	if (!vmcoreinfo) {
++		if (!get_page_offset())
++			return FALSE;
+ 
+-	/* paddr_to_vaddr() on arm64 needs phys_base. */
+-	if (!get_phys_base())
+-		return FALSE;
++		/* paddr_to_vaddr() on arm64 needs phys_base. */
++		if (!get_phys_base())
++			return FALSE;
+ 
+-	if (!vmcoreinfo) {
+ 		if (!get_sys_kernel_vmcoreinfo(&vmcoreinfo_addr, &vmcoreinfo_len))
+ 			return FALSE;
+ 
+-- 
+2.45.2
+

makedumpfile.spec

@@ -29,6 +29,7 @@ BuildRequires: gettext
 
 Patch0: 0001-PATCH-Fix-failure-of-hugetlb-pages-exclusion-on-Linu.patch
 Patch1: 0002-PATCH-Fix-wrong-exclusion-of-Slab-pages-on-Linux-6.1.patch
+Patch2: 0001-PATCH-Workaround-for-segfault-by-makedumpfile-mem-us.patch
 
 %description
 makedumpfile is a tool to compress and filter out unneeded data from kernel