From 6e5250eaa665fac681926251a8d7f5f418103399 Mon Sep 17 00:00:00 2001 From: Sourabh Jain Date: Fri, 31 Jan 2025 17:08:27 +0530 Subject: powerpc/crash: use generic APIs to locate memory hole for kdump On PowerPC, the memory reserved for the crashkernel can contain components like RTAS, TCE, OPAL, etc., which should be avoided when loading kexec segments into crashkernel memory. Due to these special components, PowerPC has its own set of APIs to locate holes in the crashkernel memory for loading kexec segments for kdump. However, for loading kexec segments in the kexec case, PowerPC already uses generic APIs to locate holes. The previous patch in this series, titled "crash: Let arch decide usable memory range in reserved area," introduced arch-specific hook to handle such special regions in the crashkernel area. So, switch PowerPC to use the generic APIs to locate memory holes for kdump and remove the redundant PowerPC-specific APIs. Link: https://lkml.kernel.org/r/20250131113830.925179-5-sourabhjain@linux.ibm.com Signed-off-by: Sourabh Jain Cc: Baoquan he Cc: Hari Bathini Cc: Madhavan Srinivasan Cc: Mahesh Salgaonkar Cc: Michael Ellerman Signed-off-by: Andrew Morton --- arch/powerpc/include/asm/kexec.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/include/asm/kexec.h') diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h index 601e569303e1..1b800df5eb30 100644 --- a/arch/powerpc/include/asm/kexec.h +++ b/arch/powerpc/include/asm/kexec.h @@ -94,8 +94,10 @@ int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long int arch_kimage_file_post_load_cleanup(struct kimage *image); #define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_cleanup -int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf); -#define arch_kexec_locate_mem_hole arch_kexec_locate_mem_hole +int arch_check_excluded_range(struct kimage *image, unsigned long start, + unsigned long end); +#define arch_check_excluded_range arch_check_excluded_range + int load_crashdump_segments_ppc64(struct kimage *image, struct kexec_buf *kbuf); -- cgit v1.2.3 From e3185ee438c28ee926cb3ef26f3bfb0aae510606 Mon Sep 17 00:00:00 2001 From: Sourabh Jain Date: Fri, 31 Jan 2025 17:08:30 +0530 Subject: powerpc/crash: use generic crashkernel reservation Commit 0ab97169aa05 ("crash_core: add generic function to do reservation") added a generic function to reserve crashkernel memory. So let's use the same function on powerpc and remove the architecture-specific code that essentially does the same thing. The generic crashkernel reservation also provides a way to split the crashkernel reservation into high and low memory reservations, which can be enabled for powerpc in the future. Along with moving to the generic crashkernel reservation, the code related to finding the base address for the crashkernel has been separated into its own function name get_crash_base() for better readability and maintainability. Link: https://lkml.kernel.org/r/20250131113830.925179-8-sourabhjain@linux.ibm.com Signed-off-by: Sourabh Jain Reviewed-by: Mahesh Salgaonkar Acked-by: Hari Bathini Cc: Baoquan he Cc: Madhavan Srinivasan Cc: Michael Ellerman Signed-off-by: Andrew Morton --- arch/powerpc/Kconfig | 3 ++ arch/powerpc/include/asm/crash_reserve.h | 8 +++ arch/powerpc/include/asm/kexec.h | 4 +- arch/powerpc/kernel/prom.c | 2 +- arch/powerpc/kexec/core.c | 90 ++++++++++++++------------------ 5 files changed, 53 insertions(+), 54 deletions(-) create mode 100644 arch/powerpc/include/asm/crash_reserve.h (limited to 'arch/powerpc/include/asm/kexec.h') diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 424f188e62d9..b7e00bb8e556 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -721,6 +721,9 @@ config ARCH_SUPPORTS_CRASH_HOTPLUG def_bool y depends on PPC64 +config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION + def_bool CRASH_RESERVE + config FA_DUMP bool "Firmware-assisted dump" depends on CRASH_DUMP && PPC64 && (PPC_RTAS || PPC_POWERNV) diff --git a/arch/powerpc/include/asm/crash_reserve.h b/arch/powerpc/include/asm/crash_reserve.h new file mode 100644 index 000000000000..6467ce29b1fa --- /dev/null +++ b/arch/powerpc/include/asm/crash_reserve.h @@ -0,0 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_CRASH_RESERVE_H +#define _ASM_POWERPC_CRASH_RESERVE_H + +/* crash kernel regions are Page size agliged */ +#define CRASH_ALIGN PAGE_SIZE + +#endif /* _ASM_POWERPC_CRASH_RESERVE_H */ diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h index 1b800df5eb30..70f2f0517509 100644 --- a/arch/powerpc/include/asm/kexec.h +++ b/arch/powerpc/include/asm/kexec.h @@ -114,9 +114,9 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt, struct crash_mem #ifdef CONFIG_CRASH_RESERVE int __init overlaps_crashkernel(unsigned long start, unsigned long size); -extern void reserve_crashkernel(void); +extern void arch_reserve_crashkernel(void); #else -static inline void reserve_crashkernel(void) {} +static inline void arch_reserve_crashkernel(void) {} static inline int overlaps_crashkernel(unsigned long start, unsigned long size) { return 0; } #endif diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index e0059842a1c6..9ed9dde7d231 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -860,7 +860,7 @@ void __init early_init_devtree(void *params) */ if (fadump_reserve_mem() == 0) #endif - reserve_crashkernel(); + arch_reserve_crashkernel(); early_reserve_mem(); if (memory_limit > memblock_phys_mem_size()) diff --git a/arch/powerpc/kexec/core.c b/arch/powerpc/kexec/core.c index f9be7bb5aa08..00e9c267b912 100644 --- a/arch/powerpc/kexec/core.c +++ b/arch/powerpc/kexec/core.c @@ -58,38 +58,20 @@ void machine_kexec(struct kimage *image) } #ifdef CONFIG_CRASH_RESERVE -void __init reserve_crashkernel(void) -{ - unsigned long long crash_size, crash_base, total_mem_sz; - int ret; - total_mem_sz = memory_limit ? memory_limit : memblock_phys_mem_size(); - /* use common parsing */ - ret = parse_crashkernel(boot_command_line, total_mem_sz, - &crash_size, &crash_base, NULL, NULL); - if (ret == 0 && crash_size > 0) { - crashk_res.start = crash_base; - crashk_res.end = crash_base + crash_size - 1; - } - - if (crashk_res.end == crashk_res.start) { - crashk_res.start = crashk_res.end = 0; - return; - } - - /* We might have got these values via the command line or the - * device tree, either way sanitise them now. */ - - crash_size = resource_size(&crashk_res); +static unsigned long long __init get_crash_base(unsigned long long crash_base) +{ #ifndef CONFIG_NONSTATIC_KERNEL - if (crashk_res.start != KDUMP_KERNELBASE) + if (crash_base != KDUMP_KERNELBASE) printk("Crash kernel location must be 0x%x\n", KDUMP_KERNELBASE); - crashk_res.start = KDUMP_KERNELBASE; + return KDUMP_KERNELBASE; #else - if (!crashk_res.start) { + unsigned long long crash_base_align; + + if (!crash_base) { #ifdef CONFIG_PPC64 /* * On the LPAR platform place the crash kernel to mid of @@ -101,45 +83,51 @@ void __init reserve_crashkernel(void) * kernel starts at 128MB offset on other platforms. */ if (firmware_has_feature(FW_FEATURE_LPAR)) - crashk_res.start = min_t(u64, ppc64_rma_size / 2, SZ_512M); + crash_base = min_t(u64, ppc64_rma_size / 2, SZ_512M); else - crashk_res.start = min_t(u64, ppc64_rma_size / 2, SZ_128M); + crash_base = min_t(u64, ppc64_rma_size / 2, SZ_128M); #else - crashk_res.start = KDUMP_KERNELBASE; + crash_base = KDUMP_KERNELBASE; #endif } - crash_base = PAGE_ALIGN(crashk_res.start); - if (crash_base != crashk_res.start) { - printk("Crash kernel base must be aligned to 0x%lx\n", - PAGE_SIZE); - crashk_res.start = crash_base; - } + crash_base_align = PAGE_ALIGN(crash_base); + if (crash_base != crash_base_align) + pr_warn("Crash kernel base must be aligned to 0x%lx\n", PAGE_SIZE); + return crash_base_align; #endif - crash_size = PAGE_ALIGN(crash_size); - crashk_res.end = crashk_res.start + crash_size - 1; +} - /* The crash region must not overlap the current kernel */ - if (overlaps_crashkernel(__pa(_stext), _end - _stext)) { - printk(KERN_WARNING - "Crash kernel can not overlap current kernel\n"); - crashk_res.start = crashk_res.end = 0; +void __init arch_reserve_crashkernel(void) +{ + unsigned long long crash_size, crash_base, crash_end; + unsigned long long kernel_start, kernel_size; + unsigned long long total_mem_sz; + int ret; + + total_mem_sz = memory_limit ? memory_limit : memblock_phys_mem_size(); + + /* use common parsing */ + ret = parse_crashkernel(boot_command_line, total_mem_sz, &crash_size, + &crash_base, NULL, NULL); + + if (ret) return; - } - printk(KERN_INFO "Reserving %ldMB of memory at %ldMB " - "for crashkernel (System RAM: %ldMB)\n", - (unsigned long)(crash_size >> 20), - (unsigned long)(crashk_res.start >> 20), - (unsigned long)(total_mem_sz >> 20)); + crash_base = get_crash_base(crash_base); + crash_end = crash_base + crash_size - 1; - if (!memblock_is_region_memory(crashk_res.start, crash_size) || - memblock_reserve(crashk_res.start, crash_size)) { - pr_err("Failed to reserve memory for crashkernel!\n"); - crashk_res.start = crashk_res.end = 0; + kernel_start = __pa(_stext); + kernel_size = _end - _stext; + + /* The crash region must not overlap the current kernel */ + if ((kernel_start + kernel_size > crash_base) && (kernel_start <= crash_end)) { + pr_warn("Crash kernel can not overlap current kernel\n"); return; } + + reserve_crashkernel_generic(crash_size, crash_base, 0, false); } int __init overlaps_crashkernel(unsigned long start, unsigned long size) -- cgit v1.2.3