Re: [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&gt;

--- 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; -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility