[Crash-utility] [PATCH] Fix reading x86_64 xendump cores on 2.6.27+
Hi,
the crash utility is unable to read xendump cores from kernel versions
2.6.27 or newer. Bernhard fixed this only for kdump Xen cores.
With 2.6.27 and newer kernels, the max_pfn symbol should be used
to get the highest PFN in the system. However, xendump code still
tries to use end_pfn. Without the patch, early initialization
fails with the error message: "crash: cannot resolve "end_pfn".
Signed-off-by: Petr Tesarik <ptesarik(a)suse.cz>
---
x86_64.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)
--- a/x86_64.c
+++ b/x86_64.c
@@ -4851,6 +4851,7 @@ x86_64_xen_kdump_p2m_create(struct xen_k
ulong frames;
ulong frame_mfn[MAX_X86_64_FRAMES] = { 0 };
int mfns[MAX_X86_64_FRAMES] = { 0 };
+ struct syment *sp;
/*
* Temporarily read physical (machine) addresses from vmcore by
@@ -4932,7 +4933,15 @@ use_cr3:
x86_64_debug_dump_page(fp, machdep->machspec->pml4,
"contents of PML4 page:");
- kvaddr = symbol_value("end_pfn");
+ /*
+ * kernel version < 2.6.27 => end_pfn
+ * kernel version >= 2.6.27 => max_pfn
+ */
+ if ((sp = symbol_search("end_pfn")))
+ kvaddr = sp->value;
+ else
+ kvaddr = symbol_value("max_pfn");
+
if (!x86_64_xen_kdump_load_page(kvaddr, xkd->page))
return FALSE;
up = (ulong *)(xkd->page + PAGEOFFSET(kvaddr));
@@ -5262,6 +5271,7 @@ x86_64_xendump_p2m_create(struct xendump
ulong mfn, kvaddr, ctrlreg[8], ctrlreg_offset;
ulong *up;
off_t offset;
+ struct syment *sp;
if (!symbol_exists("phys_to_machine_mapping")) {
xd->flags |= XC_CORE_NO_P2M;
@@ -5299,7 +5309,15 @@ x86_64_xendump_p2m_create(struct xendump
x86_64_debug_dump_page(xd->ofp, machdep->machspec->pml4,
"contents of PML4 page:");
- kvaddr = symbol_value("end_pfn");
+ /*
+ * kernel version < 2.6.27 => end_pfn
+ * kernel version >= 2.6.27 => max_pfn
+ */
+ if ((sp = symbol_search("end_pfn")))
+ kvaddr = sp->value;
+ else
+ kvaddr = symbol_value("max_pfn");
+
if (!x86_64_xendump_load_page(kvaddr, xd))
return FALSE;