On 07/03/2020 03:53 AM, Hari Bathini wrote: > This patch series enables kdump support for kexec_file_load system > call (kexec -s -p) on PPC64. The changes are inspired from kexec-tools > code but heavily modified for kernel consumption. There is scope to > expand purgatory to verify sha256 digest along with other improvements > in purgatory code. Will deal with those changes in a separate patch > series later. > > The first patch adds a weak arch_kexec_locate_mem_hole() function to > override locate memory hole logic suiting arch needs. There are some > special regions in ppc64 which should be avoided while loading buffer > & there are multiple callers to kexec_add_buffer making it complicated > to maintain range sanity and using generic lookup at the same time. > > The second patch marks ppc64 specific code within arch/powerpc/kexec > and arch/powerpc/purgatory to make the subsequent code changes easy > to understand. > > The next patch adds helper function to setup different memory ranges > needed for loading kdump kernel, booting into it and exporting the > crashing kernel's elfcore. > > The fourth patch overrides arch_kexec_locate_mem_hole() function to > locate memory hole for kdump segments by accounting for the special > memory regions, referred to as excluded memory ranges, and sets > kbuf->mem when a suitable memory region is found. > > The fifth patch moves walk_drmem_lmbs() out of .init section with > a few changes to reuse it for setting up kdump kernel's usable memory > ranges. The next patch uses walk_drmem_lmbs() to look up the LMBs > and set linux,drconf-usable-memory & linux,usable-memory properties > in order to restrict kdump kernel's memory usage. > > The seventh patch adds relocation support for the purgatory. Patch 8 > helps setup the stack for the purgatory. The next patch setups up > backup region as a segment while loading kdump kernel and teaches > purgatory to copy it from source to destination. > > Patch 10 builds the elfcore header for the running kernel & passes > the info to kdump kernel via "elfcorehdr=" parameter to export as > /proc/vmcore file. The next patch sets up the memory reserve map > for the kexec kernel and also claims kdump support for kdump as > all the necessary changes are added. > > The last patch fixes a lookup issue for `kexec -l -s` case when > memory is reserved for crashkernel. > > Tested the changes successfully on P8, P9 lpars, couple of OpenPOWER > boxes and a simulator. > > Changes in v2: > * Introduced arch_kexec_locate_mem_hole() for override and dropped > weak arch_kexec_add_buffer(). > * Addressed warnings reported by lkp. > * Added patch to address kexec load issue when memory is reserved > for crashkernel. > * Used the appropriate license header for the new files added. > * Added an option to merge ranges to minimize reallocations while > adding memory ranges. > * Dropped within_crashkernel parameter for add_opal_mem_range() & > add_rtas_mem_range() functions as it is not really needed. > > --- > > Hari Bathini (12): > kexec_file: allow archs to handle special regions while locating memory hole > powerpc/kexec_file: mark PPC64 specific code > powerpc/kexec_file: add helper functions for getting memory ranges > ppc64/kexec_file: avoid stomping memory used by special regions > powerpc/drmem: make lmb walk a bit more flexible > ppc64/kexec_file: restrict memory usage of kdump kernel > ppc64/kexec_file: add support to relocate purgatory > ppc64/kexec_file: setup the stack for purgatory > ppc64/kexec_file: setup backup region for kdump kernel > ppc64/kexec_file: prepare elfcore header for crashing kernel > ppc64/kexec_file: add appropriate regions for memory reserve map > ppc64/kexec_file: fix kexec load failure with lack of memory hole > > > arch/powerpc/include/asm/crashdump-ppc64.h | 15 > arch/powerpc/include/asm/drmem.h | 9 > arch/powerpc/include/asm/kexec.h | 35 + > arch/powerpc/include/asm/kexec_ranges.h | 18 > arch/powerpc/include/asm/purgatory.h | 11 > arch/powerpc/kernel/prom.c | 13 > arch/powerpc/kexec/Makefile | 2 > arch/powerpc/kexec/elf_64.c | 35 + > arch/powerpc/kexec/file_load.c | 78 + > arch/powerpc/kexec/file_load_64.c | 1509 ++++++++++++++++++++++++++++ > arch/powerpc/kexec/ranges.c | 397 +++++++ > arch/powerpc/mm/drmem.c | 87 +- > arch/powerpc/mm/numa.c | 13 > arch/powerpc/purgatory/Makefile | 28 - > arch/powerpc/purgatory/purgatory_64.c | 36 + > arch/powerpc/purgatory/trampoline.S | 117 -- > arch/powerpc/purgatory/trampoline_64.S | 175 +++ > include/linux/kexec.h | 29 - > kernel/kexec_file.c | 16 > 19 files changed, 2413 insertions(+), 210 deletions(-) > create mode 100644 arch/powerpc/include/asm/crashdump-ppc64.h > create mode 100644 arch/powerpc/include/asm/kexec_ranges.h > create mode 100644 arch/powerpc/include/asm/purgatory.h > create mode 100644 arch/powerpc/kexec/file_load_64.c > create mode 100644 arch/powerpc/kexec/ranges.c > create mode 100644 arch/powerpc/purgatory/purgatory_64.c > delete mode 100644 arch/powerpc/purgatory/trampoline.S > create mode 100644 arch/powerpc/purgatory/trampoline_64.S > Tested-by: Pingfan Liu <piliu@xxxxxxxxxx> _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
