Hi Akashi, On Thursday 26 March 2015 01:58 PM, AKASHI Takahiro wrote: > This patch set enables kdump (crash dump kernel) support on arm64 on top of > Geoff's kexec patchset. > > In this version, there are some arm64-specific usage/constraints: > 1) "mem=" boot parameter must be specified on crash dump kernel > 2) Kvm will not be enabled on crash dump kernel even if configured > See commit messages and Documentation/kdump/kdump.txt for details. > > The only concern I have is whether or not we can use the exact same kernel > as both system kernel and crash dump kernel. The current arm64 kernel is > not relocatable in the exact sense but I have no problems in using the same > binary for testing kdump. > > I tested the code with > - ATF v1.1 + EDK2(UEFI) v3.0-rc0 > - kernel v4.0-rc4 + Geoff' kexec v8 > on Base fast model, using my yet-to-be-submitted kexec-tools [1]. > You may want to start a kernel with the following boot parameter: > crashkernel=64M at 2240M > and try > $ kexec -p --load <vmlinux> --append ... > $ echo c > /proc/sysrq-trigger > I tried to use your kdump patches for kernel and kexec-tools. I am not able to load the crash kernel properly. I passed crashkernel=64M at 259G (My 8GB RAM starts at 256G) to primary kernel. Used following to load the crash kernel kexec -p --load vmlinux --append="$( cat /proc/cmdline ) maxcpus=1 mem=64M reset_devices" I see: kexec_load failed: Cannot assign requested address entry = 0x40c40005d0 flags = 0xb70001 What I noticed that arm64_load_other_segments does not calculate correct load address for purgatory or if I pass initrd then for that too within crash kernel allocated memory. Shouldn't we have a function similar to locate_dtb_in_crashmem for putgatory as well as initrd? I can try to fix this allocation, but I was just wondering if I understood correctly or I am missing something. ~Pratyush > To examine vmcore (/proc/vmcore), you may use > - gdb v7.7 or later > - crash + a small patch (to recognize v4.0 kernel) > > [1] https://git.linaro.org/people/takahiro.akashi/kexec-tools.git > > > AKASHI Takahiro (5): > arm64: kdump: reserve memory for crash dump kernel > arm64: kdump: implement machine_crash_shutdown() > arm64: kdump: do not go into EL2 before starting a crash dump kernel > arm64: add kdump support > arm64: enable kdump in the arm64 defconfig > > Documentation/kdump/kdump.txt | 31 ++++++++++++++- > arch/arm64/Kconfig | 12 ++++++ > arch/arm64/configs/defconfig | 1 + > arch/arm64/include/asm/kexec.h | 34 +++++++++++++++- > arch/arm64/kernel/Makefile | 1 + > arch/arm64/kernel/crash_dump.c | 71 +++++++++++++++++++++++++++++++++ > arch/arm64/kernel/machine_kexec.c | 55 +++++++++++++++++++++++++- > arch/arm64/kernel/process.c | 7 +++- > arch/arm64/kernel/setup.c | 78 +++++++++++++++++++++++++++++++++++++ > arch/arm64/kernel/smp.c | 10 ++++- > 10 files changed, 294 insertions(+), 6 deletions(-) > create mode 100644 arch/arm64/kernel/crash_dump.c >
