[Cc: Marc] On Fri, Sep 02, 2016 at 06:23:25PM +0530, Manish Jaggi wrote: > > > On 08/31/2016 11:01 AM, AKASHI Takahiro wrote: > > Manish, > > > > Thank you for testing my kdump and reporting issues. > > > > On Wed, Aug 31, 2016 at 09:11:52AM +0530, Manish Jaggi wrote: > >> Hi Akashi, > >> > >> On 08/09/2016 07:22 AM, AKASHI Takahiro wrote: > >>> This patch series adds kdump support on arm64. > >>> > >>> To load a crash-dump kernel to the systems, a series of patches to > >>> kexec-tools, which have not yet been merged upstream, are needed. > >>> Please use my kdump patches [1]. > >>> > >>> To examine vmcore (/proc/vmcore) on a crash-dump kernel, you can use > >>> - crash utility (coming v7.1.6 or later) [2] > >>> (Necessary patches have already been queued in the master.) > >>> > >>> [1] T.B.D. > >>> [2] https://github.com/crash-utility/crash.git > >>> > >>> Changes for v24 (Aug 9, 2016): > >>> o Rebase to Linux-4.8-rc1 > >>> o Update descriptions about newly added DT proerties > >>> > >>> Changes for v23 (July 26, 2016): > >>> > >>> o Move memblock_reserve() to a single place in reserve_crashkernel() > >>> o Use cpu_park_loop() in ipi_cpu_crash_stop() > >>> o Always enforce ARCH_LOW_ADDRESS_LIMIT to the memory range of crash kernel > >>> o Re-implement fdt_enforce_memory_region() to remove non-reserve regions > >>> (for ACPI) from usable memory at crash kernel > >>> > >>> Changes for v22 (July 12, 2016): > >>> > >>> o Export "crashkernel-base" and "crashkernel-size" via device-tree, > >>> and add some descriptions about them in chosen.txt > >>> o Rename "usable-memory" to "usable-memory-range" to avoid inconsistency > >>> with powerpc's "usable-memory" > >>> o Make cosmetic changes regarding "ifdef" usage > >>> o Correct some wordings in kdump.txt > >>> > >>> Changes for v21 (July 6, 2016): > >>> > >>> o Remove kexec patches. > >>> o Rebase to arm64's for-next/core (Linux-4.7-rc4 based). > >>> o Clarify the description about kvm in kdump.txt. > >>> > >>> See the following link [3] for older changes: > >>> [3] http://lists.infradead.org/pipermail/linux-arm-kernel/2016-June/438780.html > >>> > >>> AKASHI Takahiro (8): > >>> arm64: kdump: reserve memory for crash dump kernel > >>> memblock: add memblock_cap_memory_range() > >>> arm64: limit memory regions based on DT property, usable-memory-range > >>> arm64: kdump: implement machine_crash_shutdown() > >>> arm64: kdump: add kdump support > >>> arm64: kdump: add VMCOREINFO's for user-space coredump tools > >>> arm64: kdump: enable kdump in the arm64 defconfig > >>> arm64: kdump: update a kernel doc > >>> > >>> James Morse (1): > >>> Documentation: dt: chosen properties for arm64 kdump > >>> > >>> Documentation/devicetree/bindings/chosen.txt | 45 ++++++ > >>> Documentation/kdump/kdump.txt | 16 ++- > >>> arch/arm64/Kconfig | 11 ++ > >>> arch/arm64/configs/defconfig | 1 + > >>> arch/arm64/include/asm/hardirq.h | 2 +- > >>> arch/arm64/include/asm/kexec.h | 41 +++++- > >>> arch/arm64/include/asm/smp.h | 2 + > >>> arch/arm64/kernel/Makefile | 1 + > >>> arch/arm64/kernel/crash_dump.c | 71 ++++++++++ > >>> arch/arm64/kernel/machine_kexec.c | 67 ++++++++- > >>> arch/arm64/kernel/setup.c | 7 +- > >>> arch/arm64/kernel/smp.c | 63 +++++++++ > >>> arch/arm64/mm/init.c | 202 +++++++++++++++++++++++++++ > >>> include/linux/memblock.h | 1 + > >>> mm/memblock.c | 28 ++++ > >>> 15 files changed, 551 insertions(+), 7 deletions(-) > >>> create mode 100644 arch/arm64/kernel/crash_dump.c > >>> > >> Couple of points > >> a) Just a note, while testing, the crashkernel reserved memory should be less than ARCH_LOW_ADDRESS_LIMIT (=arm64_dma_phys_limit). > > > > I think that this is a common mistake not only for kdump, but also > > for general kernels. > > Since request_standard_resources() calls alloc_bootmem_low(), > > the kernel will panic if any of usable "System RAM" is located > > above ARCH_LOW_ADDRESS_LIMIT. > > For kdump, using "crashkernel=SS" notation is a convenient way > > to avoid this issue. > > > >> b) Has anyone tested this on a SoC with Gicv3 ITS ? > >> Should the GICD/R be reset prior to switching to crash kernel ? > >> I am seeing lot of GICv3: RWP timeout, gone fishing while crash kernel boots. > > > > I've never seen this kind of messages. > > I usually do my testing on a fast model. > > "compatible" of interrupt-controller is "arm,gic-v3." > > > I suspect gic_cpu_pm_notifier is not being called on any of the cores prior to start of crash kernel. > We might have to call it explicitly. I'm not sure that it is the cause, but anyway none of any cpu_pm_notifier's will be called at panic. That is the reason why "maxcpus=1" should be specified (for kdump on arm64). -Takahiro AKASHI > > Thanks, > > -Takahiro AKASHI > > > >> Thanks, > >> Manish
