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2026-06-30riscv: kexec_file: Add support for crashkernel CMA reservationJinjie Ruan
Commit 35c18f2933c5 ("Add a new optional ",cma" suffix to the crashkernel= command line option") and commit ab475510e042 ("kdump: implement reserve_crashkernel_cma") added CMA support for kdump crashkernel reservation. This allows the kernel to dynamically allocate contiguous memory for crash dumping when needed, rather than permanently reserving a fixed region at boot time. So extend crashkernel CMA reservation support to riscv. The following changes are made to enable CMA reservation: - Parse and obtain the CMA reservation size along with other crashkernel parameters. - Call reserve_crashkernel_cma() to allocate the CMA region for kdump. - Include the CMA-reserved ranges for kdump kernel to use, which was already done in of_kexec_alloc_and_setup_fdt(). - Exclude the CMA-reserved ranges from the crash kernel memory to prevent them from being exported through /proc/vmcore, which was already done in the crash core. Update kernel-parameters.txt to document CMA support for crashkernel on riscv architecture. Cc: Paul Walmsley <pjw@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Acked-by: Baoquan He <bhe@redhat.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Paul Walmsley <pjw@kernel.org> # arch/riscv Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Link: https://patch.msgid.link/20260629094746.191843-11-ruanjinjie@huawei.com Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
2026-06-30riscv: kexec_file: Use crash_prepare_headers() helper to simplify codeJinjie Ruan
Use the newly introduced crash_prepare_headers() function to replace the existing prepare_elf_headers(), allocate cmem and exclude crash kernel memory in the crash core, which reduce code duplication. Only the following two architecture functions need to be implemented: - arch_get_system_nr_ranges(). Call get_nr_ram_ranges_callback() to pre-counts the max number of memory ranges. - arch_crash_populate_cmem(). Use prepare_elf64_ram_headers_callback() to collects the memory ranges and fills them into cmem. Cc: Paul Walmsley <pjw@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Guo Ren <guoren@kernel.org> Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Reviewed-by: Guo Ren <guoren@kernel.org> Link: https://patch.msgid.link/20260629094746.191843-7-ruanjinjie@huawei.com Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
2026-06-30riscv: kexec_file: Fix crashk_low_res not exclude bugJinjie Ruan
As done in commit 944a45abfabc ("arm64: kdump: Reimplement crashkernel=X") and commit 4831be702b95 ("arm64/kexec: Fix missing extra range for crashkres_low.") for arm64, while implementing crashkernel=X,[high,low], riscv should have excluded the "crashk_low_res" reserved ranges from the crash kernel memory to prevent them from being exported through /proc/vmcore, and the exclusion would need an extra crash_mem range. Just simply tested on qemu with crashkernel=4G with kexec in [1] mentioned in [2]. And the second kernel can be started normally. # dmesg | grep crash [ 0.000000] crashkernel low memory reserved: 0xf8000000 - 0x100000000 (128 MB) [ 0.000000] crashkernel reserved: 0x000000017fe00000 - 0x000000027fe00000 (4096 MB) [1]: https://github.com/chenjh005/kexec-tools/tree/build-test-riscv-v2 [2]: https://lore.kernel.org/all/20230726175000.2536220-1-chenjiahao16@huawei.com/ Cc: Guo Ren <guoren@kernel.org> Cc: Baoquan He <bhe@redhat.com> Fixes: 5882e5acf18d ("riscv: kdump: Implement crashkernel=X,[high,low]") Reviewed-by: Guo Ren <guoren@kernel.org> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Link: https://github.com/chenjh005/kexec-tools/tree/build-test-riscv-v2 Link: https://lore.kernel.org/all/20230726175000.2536220-1-chenjiahao16@huawei.com/ Link: https://patch.msgid.link/20260629094746.191843-2-ruanjinjie@huawei.com Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
2026-06-06riscv: kexec_file: Constrain segment placement to direct mapHan Gao
When kexec_file_load places segments with buf_max=ULONG_MAX and top_down=true, they land at the highest available physical addresses. On RISC-V the size of the linear mapping is determined by the active VM mode: SV39 caps the direct map at roughly 128GB, while SV48/SV57 extend the range substantially further. When the installed physical memory exceeds the direct map size of the active mode, top-down placement puts DTB/initrd at physical addresses outside the linearly mapped region. The kexec'd kernel cannot reach them during early boot, triggering a page fault at memcmp in start_kernel. Fix by constraining buf_max to PFN_PHYS(max_low_pfn), which reflects the runtime direct map boundary for the active VM mode (SV39/SV48/ SV57). This keeps all kexec segments within the linearly mapped region while preserving the upstream top_down allocation strategy. Signed-off-by: Han Gao <gaohan@iscas.ac.cn> Link: https://patch.msgid.link/20260519170641.123517-1-gaohan@iscas.ac.cn Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-02-21Convert 'alloc_flex' family to use the new default GFP_KERNEL argumentLinus Torvalds
This is the exact same thing as the 'alloc_obj()' version, only much smaller because there are a lot fewer users of the *alloc_flex() interface. As with alloc_obj() version, this was done entirely with mindless brute force, using the same script, except using 'flex' in the pattern rather than 'objs*'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2025-09-16riscv: Strengthen duplicate and inconsistent definition of RV_X()Alexandre Ghiti
RV_X() macro is defined in two different ways which is error prone. So harmonize its first definition and add another macro RV_X_MASK() for the second one. Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20250620-dev-alex-insn_duplicate_v5_manual-v5-2-d865dc9ad180@rivosinc.com [pjw@kernel.org: upcase the macro name to conform with previous practice] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-09-05riscv: kexec: Initialize kexec_buf structBreno Leitao
The kexec_buf structure was previously declared without initialization. commit bf454ec31add ("kexec_file: allow to place kexec_buf randomly") added a field that is always read but not consistently populated by all architectures. This un-initialized field will contain garbage. This is also triggering a UBSAN warning when the uninitialized data was accessed: ------------[ cut here ]------------ UBSAN: invalid-load in ./include/linux/kexec.h:210:10 load of value 252 is not a valid value for type '_Bool' Zero-initializing kexec_buf at declaration ensures all fields are cleanly set, preventing future instances of uninitialized memory being used. Fixes: bf454ec31add ("kexec_file: allow to place kexec_buf randomly") Signed-off-by: Breno Leitao <leitao@debian.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250827-kbuf_all-v1-2-1df9882bb01a@debian.org Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-06-05riscv: kexec_file: Support loading Image binary fileSong Shuai
This patch creates image_kexec_ops to load Image binary file for kexec_file_load() syscall. Signed-off-by: Song Shuai <songshuaishuai@tinylab.org> Signed-off-by: Björn Töpel <bjorn@rivosinc.com> Link: https://lore.kernel.org/r/20250409193004.643839-3-bjorn@kernel.org Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2025-06-05riscv: kexec_file: Split the loading of kernel and othersSong Shuai
This is the preparative patch for kexec_file_load Image support. It separates the elf_kexec_load() as two parts: - the first part loads the vmlinux (or Image) - the second part loads other segments (e.g. initrd,fdt,purgatory) And the second part is exported as the load_extra_segments() function which would be used in both kexec-elf.c and kexec-image.c. No functional change intended. Signed-off-by: Song Shuai <songshuaishuai@tinylab.org> Signed-off-by: Björn Töpel <bjorn@rivosinc.com> Link: https://lore.kernel.org/r/20250409193004.643839-2-bjorn@kernel.org Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2022-05-19RISC-V: Add kexec_file supportLiao Chang
This patch adds support for kexec_file on RISC-V. I tested it on riscv64 QEMU with busybear-linux and single core along with the OpenSBI firmware fw_jump.bin for generic platform. On SMP system, it depends on CONFIG_{HOTPLUG_CPU, RISCV_SBI} to resume/stop hart through OpenSBI firmware, it also needs a OpenSBI that support the HSM extension. Signed-off-by: Liao Chang <liaochang1@huawei.com> Signed-off-by: Li Zhengyu <lizhengyu3@huawei.com> Link: https://lore.kernel.org/r/20220408100914.150110-4-lizhengyu3@huawei.com [Palmer: Make 64-bit only] Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>