Re: [Crash-utility] [PATCH 0/1] arm64: Fix missing offset for modules_vaddr with aarch64 guest dump

----- Original Message ----- > > > ----- Original Message ----- > > On Mon, Jan 27, 2020 at 10:17:51AM -0500, Dave Anderson wrote: > > > > > > > > > ----- Original Message ----- > > > > On Mon, Jan 27, 2020 at 09:56:53AM -0500, Dave Anderson wrote: > > > > > > > > > > > > > > > ----- Original Message ----- > > > > > > From: Masayoshi Mizuma <m.mizuma(a)jp.fujitsu.com&gt; > > > > > > > > > > > > Fix for aarch64 with Linux v5.0 and later kernels that > > > > > > contains commit 91fc957c9b1d ("arm64/bpf: don't allocate > > > > > > BPF JIT programs in module memory") and the memory dump > > > > > > is captured by virsh dump. > > > > > > > > > > > > Note: Another two issues remain for the memory dump captured by > > > > > > virsh dump with aarch64. > > > > > > > > > > I'm confused -- the vmcoreinfo data has been passed to the KVM host > > > > > for the virsh dump for quite some time now. Is it not passed back > > > > > to the host on aarch64? > > > > > > > > The vmcore_data shows that vmcoreinfo size is 0, so I think vmcoreinfo > > > > isn't captured by virsh dump. > > > > Am I missing something...? > > > > > > I'm not sure -- are you using "virsh dump --memory-only ..."? > > > > Yes, I'm using --memory-only option like as: > > > > virsh dump --crash --memory-only <Guest> <Dumpfile> > > OK, then that's news to me. We went through this a while ago on x86_64 > because it required the vmcoreinfo "phys_base". It took awhile to get > it upstream, but now the whole vmcoreinfo note is passed for virsh dump > to include with the dumpfile. Maybe it's x86_64 only? Looking back through old bugzillas, google, etc, it does seem to indicate that the support covers "arm/x86", which I presume covers aarch64. See kernel commit 2d6d60a3d3eca50bbb20052278cb11dabcf4dff3 titled "fw_cfg: write vmcoreinfo details". I see a few old postings from Daisuke that indicate the the vmcoreinfo device has be registered with a "devices" or "features" file on the host (?) by using "virsh edit"? Again, sorry, I'm clueless.

Anyway, Daisuke should be able fill in the details. Dave > > Dave > > > > > > - Masa > > > > > > > > Dave > > > > > > > > > > > > > > ./crash -d1 vmlinux-v5.4 dump.v5.4 > > > > ... > > > > vmcore_data: > > > > flags: c0 (KDUMP_LOCAL|KDUMP_ELF64) > > > > ndfd: 3 > > > > ofp: ffffa5e81588 > > > > header_size: 30896 > > > > num_pt_load_segments: 1 > > > > pt_load_segment[0]: > > > > file_offset: 78b0 > > > > phys_start: 40000000 > > > > phys_end: 260000000 > > > > zero_fill: 0 > > > > elf_header: 2ed6d4e0 > > > > elf32: 0 > > > > notes32: 0 > > > > load32: 0 > > > > elf64: 2ed6d4e0 > > > > notes64: 2ed6d520 > > > > load64: 2ed6d558 > > > > sect0_64: 0 > > > > nt_prstatus: 2ed6d590 > > > > nt_prpsinfo: 0 > > > > nt_taskstruct: 0 > > > > task_struct: 0 > > > > arch_data1: (unused) > > > > arch_data2: (unused) > > > > switch_stack: 0 > > > > page_size: 0 > > > > xen_kdump_data: (unused) > > > > num_prstatus_notes: 32 > > > > num_qemu_notes: 0 > > > > vmcoreinfo: 0 > > > > size_vmcoreinfo: 0 > > > > nt_prstatus_percpu: > > > > 000000002ed6d590 000000002ed6d950 000000002ed6dd10 > > > > 000000002ed6e0d0 > > > > 000000002ed6e490 000000002ed6e850 000000002ed6ec10 > > > > 000000002ed6efd0 > > > > 000000002ed6f390 000000002ed6f750 000000002ed6fb10 > > > > 000000002ed6fed0 > > > > 000000002ed70290 000000002ed70650 000000002ed70a10 > > > > 000000002ed70dd0 > > > > 000000002ed71190 000000002ed71550 000000002ed71910 > > > > 000000002ed71cd0 > > > > 000000002ed72090 000000002ed72450 000000002ed72810 > > > > 000000002ed72bd0 > > > > 000000002ed72f90 000000002ed73350 000000002ed73710 > > > > 000000002ed73ad0 > > > > 000000002ed73e90 000000002ed74250 000000002ed74610 > > > > 000000002ed749d0 > > > > nt_qemu_percpu: > > > > backup_src_start: 0 > > > > backup_src_size: 0 > > > > backup_offset: 0 > > > > ... > > > > > > > > Thanks, > > > > Masa > > > > > > > > > > > > > > Dave > > > > > > > > > > I > > > > > > > > > > > > 1. KASLR > > > > > > crash doesn't work in case KASLR is enabled on the guest. > > > > > > That is because the memory dump doesn't have vmcoreinfo, so we > > > > > > cannot get the relocation position. > > > > > > I suppose we need to implement calc_kaslr_offset() for aarch64. > > > > > > nokaslr with the guest kernel parameter is a workaround. > > > > > > > > > > > > 2. VA_BITS > > > > > > crash doesn't work in case the guest kernel is v5.4 and later. > > > > > > That is because the memory dump doesn't have vmcoreinfo, so we > > > > > > cannot get vabits_actual. > > > > > > I think there's no workaround so far... > > > > > > > > > > > > Masayoshi Mizuma (1): > > > > > > arm64: Fix missing offset for modules_vaddr with aarch64 guest > > > > > > dump > > > > > > > > > > > > arm64.c | 2 ++ > > > > > > defs.h | 3 +++ > > > > > > 2 files changed, 5 insertions(+) > > > > > > > > > > > > -- > > > > > > 2.18.1 > > > > > > > > > > > > > > > > > > -- > > > > > > Crash-utility mailing list > > > > > > Crash-utility(a)redhat.com > > > > > > https://www.redhat.com/mailman/listinfo/crash-utility > > > > > > > > > > > > > > > > -- > > > > > Crash-utility mailing list > > > > > Crash-utility(a)redhat.com > > > > > https://www.redhat.com/mailman/listinfo/crash-utility > > > > > > > > > > > > > > > > > > > > > > -- > Crash-utility mailing list > Crash-utility(a)redhat.com > https://www.redhat.com/mailman/listinfo/crash-utility >