Changes from v1: --------------- - Added the support for older kernels, where we determine the PHYS_OFFSET value from PT_LOAD segments inside 'kcore'. - Improved commit logs since v1. On certain arm64 platforms, it has been noticed that due to a hole at the start of physical ram exposed to kernel (i.e. it doesn't start from address 0), the kernel still calculates the 'memstart_addr' kernel variable as 0. Whereas the SYSTEM_RAM or IOMEM_RESERVED range in '/proc/iomem' would carry a first entry whose start address is non-zero (as the physical ram exposed to the kernel starts from a non-zero address). In such cases, if we rely on '/proc/iomem' entries to calculate the phys_offset, then we will have mismatch between the user-space and kernel space 'PHYS_OFFSET' value. The present 'kexec-tools' code does the same in 'get_memory_ranges_iomem_cb()' function when it makes a call to 'set_phys_offset()'. This can cause the vmcore generated via 'kexec-tools' to miss the last few bytes as the first '/proc/iomem' starts from a non-zero address. Please see [0] for the original bug-report from Yanjiang Jin. This patchset tries to fix the same. Details about the patches in this series: ---------------------------------------- PATCH 1/2 -> - Tries to move the elf read functionality from 'vmcore-dmesg.c' to a new utility library named 'elf_info.c', so that subsequent patches can use the same. - See the patch log for more details. PATCH 2/2 -> - Implements the actual functionality of reading the PHYS_OFFSET for arm64 platforms from the kcore (either VMCOREINFO PT_NOTE inside 'kcore' or from the PT_LOAD segments inside 'kcore'). - See the patch log for more details. [0] https://www.spinics.net/lists/kexec/msg20618.html Bhupesh Sharma (2): util_lib: Add functionality to read elf notes arm64: Add support to read PHYS_OFFSET from 'kcore' - pt_note or pt_load (if available) kexec/arch/arm64/kexec-arm64.c | 194 +++++- kexec/arch/arm64/kexec-arm64.h | 15 +- util_lib/Makefile | 4 +- vmcore-dmesg/vmcore-dmesg.c => util_lib/elf_info.c | 193 ++++-- util_lib/include/elf_info.h | 35 + vmcore-dmesg/Makefile | 4 +- vmcore-dmesg/vmcore-dmesg.c | 742 +-------------------- 7 files changed, 386 insertions(+), 801 deletions(-) copy vmcore-dmesg/vmcore-dmesg.c => util_lib/elf_info.c (86%) create mode 100644 util_lib/include/elf_info.h -- 2.7.4 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
