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. > Thanks, > -Takahiro AKASHI > >> Thanks, >> Manish
