kernel/arch/arm64/include/asm/kexec.h, branch linux-6.2.y

kexec: drop weak attribute from functions

2022-07-15T16:21:16Z

Drop __weak attribute from functions in kexec_core.c: - machine_kexec_post_load() - arch_kexec_protect_crashkres() - arch_kexec_unprotect_crashkres() - crash_free_reserved_phys_range() Link: https://lkml.kernel.org/r/c0f6219e03cb399d166d518ab505095218a902dd.1656659357.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Naveen N. Rao Suggested-by: Eric Biederman Signed-off-by: Andrew Morton Signed-off-by: Mimi Zohar

kexec_file: drop weak attribute from functions

2022-07-15T16:21:16Z

As requested (http://lkml.kernel.org/r/87ee0q7b92.fsf@email.froward.int.ebiederm.org), this series converts weak functions in kexec to use the #ifdef approach. Quoting the 3e35142ef99fe ("kexec_file: drop weak attribute from arch_kexec_apply_relocations[_add]") changelog: : Since commit d1bcae833b32f1 ("ELF: Don't generate unused section symbols") : [1], binutils (v2.36+) started dropping section symbols that it thought : were unused. This isn't an issue in general, but with kexec_file.c, gcc : is placing kexec_arch_apply_relocations[_add] into a separate : .text.unlikely section and the section symbol ".text.unlikely" is being : dropped. Due to this, recordmcount is unable to find a non-weak symbol in : .text.unlikely to generate a relocation record against. This patch (of 2); Drop __weak attribute from functions in kexec_file.c: - arch_kexec_kernel_image_probe() - arch_kimage_file_post_load_cleanup() - arch_kexec_kernel_image_load() - arch_kexec_locate_mem_hole() - arch_kexec_kernel_verify_sig() arch_kexec_kernel_image_load() calls into kexec_image_load_default(), so drop the static attribute for the latter. arch_kexec_kernel_verify_sig() is not overridden by any architecture, so drop the __weak attribute. Link: https://lkml.kernel.org/r/cover.1656659357.git.naveen.n.rao@linux.vnet.ibm.com Link: https://lkml.kernel.org/r/2cd7ca1fe4d6bb6ca38e3283c717878388ed6788.1656659357.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Naveen N. Rao Suggested-by: Eric Biederman Signed-off-by: Andrew Morton Signed-off-by: Mimi Zohar

arm64: kexec: remove cpu-reset.h

2021-10-01T12:31:00Z

This header contains only cpu_soft_restart() which is never used directly anymore. So, remove this header, and rename the helper to be cpu_soft_restart(). Suggested-by: James Morse Signed-off-by: Pasha Tatashin Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/20210930143113.1502553-15-pasha.tatashin@soleen.com Signed-off-by: Will Deacon

arm64: kexec: keep MMU enabled during kexec relocation

2021-10-01T12:31:00Z

Now, that we have linear map page tables configured, keep MMU enabled to allow faster relocation of segments to final destination. Cavium ThunderX2: Kernel Image size: 38M Iniramfs size: 46M Total relocation size: 84M MMU-disabled: relocation 7.489539915s MMU-enabled: relocation 0.03946095s Broadcom Stingray: The performance data: for a moderate size kernel + initramfs: 25M the relocation was taking 0.382s, with enabled MMU it now takes 0.019s only or x20 improvement. The time is proportional to the size of relocation, therefore if initramfs is larger, 100M it could take over a second. Signed-off-by: Pasha Tatashin Tested-by: Pingfan Liu Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/20210930143113.1502553-13-pasha.tatashin@soleen.com Signed-off-by: Will Deacon

arm64: kexec: install a copy of the linear-map

2021-10-01T12:31:00Z

To perform the kexec relocation with the MMU enabled, we need a copy of the linear map. Create one, and install it from the relocation code. This has to be done from the assembly code as it will be idmapped with TTBR0. The kernel runs in TTRB1, so can't use the break-before-make sequence on the mapping it is executing from. The makes no difference yet as the relocation code runs with the MMU disabled. Suggested-by: James Morse Signed-off-by: Pasha Tatashin Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/20210930143113.1502553-12-pasha.tatashin@soleen.com Signed-off-by: Will Deacon

arm64: kexec: configure EL2 vectors for kexec

2021-10-01T12:31:00Z

If we have a EL2 mode without VHE, the EL2 vectors are needed in order to switch to EL2 and jump to new world with hypervisor privileges. In preparation to MMU enabled relocation, configure our EL2 table now. Kexec uses #HVC_SOFT_RESTART to branch to the new world, so extend el1_sync vector that is provided by trans_pgd_copy_el2_vectors() to support this case. Signed-off-by: Pasha Tatashin Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/20210930143113.1502553-9-pasha.tatashin@soleen.com Signed-off-by: Will Deacon

arm64: Use ELF fields defined in 'struct kimage'

2021-03-08T19:06:28Z

ELF related fields elf_headers, elf_headers_sz, and elf_headers_mem have been moved from 'struct kimage_arch' to 'struct kimage' as elf_headers, elf_headers_sz, and elf_load_addr respectively. Use the ELF fields defined in 'struct kimage'. Suggested-by: Rob Herring Reported-by: kernel test robot Signed-off-by: Lakshmi Ramasubramanian Reviewed-by: Thiago Jung Bauermann Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20210221174930.27324-3-nramas@linux.microsoft.com

arm64: kexec: move relocation function setup

2021-01-27T15:41:12Z

Currently, kernel relocation function is configured in machine_kexec() at the time of kexec reboot by using control_code_page. This operation, however, is more logical to be done during kexec_load, and thus remove from reboot time. Move, setup of this function to newly added machine_kexec_post_load(). Because once MMU is enabled, kexec control page will contain more than relocation kernel, but also vector table, add pointer to the actual function within this page arch.kern_reloc. Currently, it equals to the beginning of page, we will add offsets later, when vector table is added. Signed-off-by: Pavel Tatashin Reviewed-by: James Morse Link: https://lore.kernel.org/r/20210125191923.1060122-10-pasha.tatashin@soleen.com Signed-off-by: Will Deacon

arm64: kexec: make dtb_mem always enabled

2021-01-27T15:41:11Z

Currently, dtb_mem is enabled only when CONFIG_KEXEC_FILE is enabled. This adds ugly ifdefs to c files. Always enabled dtb_mem, when it is not used, it is NULL. Change the dtb_mem to phys_addr_t, as it is a physical address. Signed-off-by: Pavel Tatashin Reviewed-by: James Morse Link: https://lore.kernel.org/r/20210125191923.1060122-2-pasha.tatashin@soleen.com Signed-off-by: Will Deacon

arm64: kexec_file: add crash dump support

2020-01-08T17:05:23Z

Enabling crash dump (kdump) includes * prepare contents of ELF header of a core dump file, /proc/vmcore, using crash_prepare_elf64_headers(), and * add two device tree properties, "linux,usable-memory-range" and "linux,elfcorehdr", which represent respectively a memory range to be used by crash dump kernel and the header's location Signed-off-by: AKASHI Takahiro Cc: Catalin Marinas Cc: Will Deacon Reviewed-by: James Morse Tested-and-reviewed-by: Bhupesh Sharma Signed-off-by: Will Deacon