Re: [PATCH v3 2/5] RISC-V: Add kexec support
Στις 2021-04-06 21:38, Alex Ghiti έγραψε: Le 4/5/21 à 4:57 AM, Nick Kossifidis a écrit : + +/* Reserve a page for the control code buffer */ +#define KEXEC_CONTROL_PAGE_SIZE 4096 PAGE_SIZE instead ? Yup, I'll change it. +obj-${CONFIG_KEXEC}+= kexec_relocate.o machine_kexec.o Other obj-$() use parenthesis. ACK + li s5, ((1 << PAGE_SHIFT) / RISCV_SZPTR) 1 << PAGE_SHIFT = PAGE_SIZE ACK +#if defined(CONFIG_HOTPLUG_CPU) && (CONFIG_SMP) Shouldn't it be defined(CONFIG_SMP) ? It depends on SMP anyway, I'll remove the second part.
Re: [PATCH v3 2/5] RISC-V: Add kexec support
Le 4/5/21 à 4:57 AM, Nick Kossifidis a écrit : This patch adds support for kexec on RISC-V. On SMP systems it depends on HOTPLUG_CPU in order to be able to bring up all harts after kexec. It also needs a recent OpenSBI version that supports the HSM extension. I tested it on riscv64 QEMU on both an smp and a non-smp system. v5: * For now depend on MMU, further changes needed for NOMMU support * Make sure stvec is aligned * Cleanup some unneeded fences * Verify control code's buffer size * Compile kexec_relocate.S with medany and norelax v4: * No functional changes, just re-based v3: * Use the new smp_shutdown_nonboot_cpus() call. * Move riscv_kexec_relocate to .rodata v2: * Pass needed parameters as arguments to riscv_kexec_relocate instead of using global variables. * Use kimage_arch to hold the fdt address of the included fdt. * Use SYM_* macros on kexec_relocate.S. * Compatibility with STRICT_KERNEL_RWX. * Compatibility with HOTPLUG_CPU for SMP * Small cleanups Signed-off-by: Nick Kossifidis --- arch/riscv/Kconfig | 15 +++ arch/riscv/include/asm/kexec.h | 47 arch/riscv/kernel/Makefile | 5 + arch/riscv/kernel/kexec_relocate.S | 156 arch/riscv/kernel/machine_kexec.c | 186 + 5 files changed, 409 insertions(+) create mode 100644 arch/riscv/include/asm/kexec.h create mode 100644 arch/riscv/kernel/kexec_relocate.S create mode 100644 arch/riscv/kernel/machine_kexec.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 8ea60a0a1..3716262ef 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -389,6 +389,21 @@ config RISCV_SBI_V01 help This config allows kernel to use SBI v0.1 APIs. This will be deprecated in future once legacy M-mode software are no longer in use. + +config KEXEC + bool "Kexec system call" + select KEXEC_CORE + select HOTPLUG_CPU if SMP + depends on MMU + help + kexec is a system call that implements the ability to shutdown your + current kernel, and to start another kernel. It is like a reboot + but it is independent of the system firmware. And like a reboot + you can start any kernel with it, not just Linux. + + The name comes from the similarity to the exec system call. + + endmenu menu "Boot options" diff --git a/arch/riscv/include/asm/kexec.h b/arch/riscv/include/asm/kexec.h new file mode 100644 index 0..efc69feb4 --- /dev/null +++ b/arch/riscv/include/asm/kexec.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 FORTH-ICS/CARV + * Nick Kossifidis + */ + +#ifndef _RISCV_KEXEC_H +#define _RISCV_KEXEC_H + +/* Maximum physical address we can use pages from */ +#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL) + +/* Maximum address we can reach in physical address mode */ +#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL) + +/* Maximum address we can use for the control code buffer */ +#define KEXEC_CONTROL_MEMORY_LIMIT (-1UL) + +/* Reserve a page for the control code buffer */ +#define KEXEC_CONTROL_PAGE_SIZE 4096 PAGE_SIZE instead ? + +#define KEXEC_ARCH KEXEC_ARCH_RISCV + +static inline void +crash_setup_regs(struct pt_regs *newregs, +struct pt_regs *oldregs) +{ + /* Dummy implementation for now */ +} + + +#define ARCH_HAS_KIMAGE_ARCH + +struct kimage_arch { + unsigned long fdt_addr; +}; + +const extern unsigned char riscv_kexec_relocate[]; +const extern unsigned int riscv_kexec_relocate_size; + +typedef void (*riscv_kexec_do_relocate)(unsigned long first_ind_entry, + unsigned long jump_addr, + unsigned long fdt_addr, + unsigned long hartid, + unsigned long va_pa_off); + +#endif diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 3dc0abde9..c2594018c 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -9,6 +9,10 @@ CFLAGS_REMOVE_patch.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_sbi.o = $(CC_FLAGS_FTRACE) endif +ifdef CONFIG_KEXEC +AFLAGS_kexec_relocate.o := -mcmodel=medany -mno-relax +endif + extra-y += head.o extra-y += vmlinux.lds @@ -54,6 +58,7 @@ obj-$(CONFIG_SMP) += cpu_ops_sbi.o endif obj-$(CONFIG_HOTPLUG_CPU) += cpu-hotplug.o obj-$(CONFIG_KGDB)+= kgdb.o +obj-${CONFIG_KEXEC}+= kexec_relocate.o machine_kexec.o Other obj-$() use parenthesis. obj-$(CONFIG_JUMP_LABEL) += jump_label.o diff --git a/arch/riscv/kernel/kexec_relocate.S b/arch/riscv/kernel/kexec_relocate.S new file mode 100644 index 0..616c20771 --- /dev/null +++ b/arch/riscv/kernel/kexec_relocate.S @@ -0,0 +1,156 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 FORTH-ICS/CARV + * Nick Kossifidis + */ + +#include
[PATCH v3 2/5] RISC-V: Add kexec support
This patch adds support for kexec on RISC-V. On SMP systems it depends on HOTPLUG_CPU in order to be able to bring up all harts after kexec. It also needs a recent OpenSBI version that supports the HSM extension. I tested it on riscv64 QEMU on both an smp and a non-smp system. v5: * For now depend on MMU, further changes needed for NOMMU support * Make sure stvec is aligned * Cleanup some unneeded fences * Verify control code's buffer size * Compile kexec_relocate.S with medany and norelax v4: * No functional changes, just re-based v3: * Use the new smp_shutdown_nonboot_cpus() call. * Move riscv_kexec_relocate to .rodata v2: * Pass needed parameters as arguments to riscv_kexec_relocate instead of using global variables. * Use kimage_arch to hold the fdt address of the included fdt. * Use SYM_* macros on kexec_relocate.S. * Compatibility with STRICT_KERNEL_RWX. * Compatibility with HOTPLUG_CPU for SMP * Small cleanups Signed-off-by: Nick Kossifidis --- arch/riscv/Kconfig | 15 +++ arch/riscv/include/asm/kexec.h | 47 arch/riscv/kernel/Makefile | 5 + arch/riscv/kernel/kexec_relocate.S | 156 arch/riscv/kernel/machine_kexec.c | 186 + 5 files changed, 409 insertions(+) create mode 100644 arch/riscv/include/asm/kexec.h create mode 100644 arch/riscv/kernel/kexec_relocate.S create mode 100644 arch/riscv/kernel/machine_kexec.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 8ea60a0a1..3716262ef 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -389,6 +389,21 @@ config RISCV_SBI_V01 help This config allows kernel to use SBI v0.1 APIs. This will be deprecated in future once legacy M-mode software are no longer in use. + +config KEXEC + bool "Kexec system call" + select KEXEC_CORE + select HOTPLUG_CPU if SMP + depends on MMU + help + kexec is a system call that implements the ability to shutdown your + current kernel, and to start another kernel. It is like a reboot + but it is independent of the system firmware. And like a reboot + you can start any kernel with it, not just Linux. + + The name comes from the similarity to the exec system call. + + endmenu menu "Boot options" diff --git a/arch/riscv/include/asm/kexec.h b/arch/riscv/include/asm/kexec.h new file mode 100644 index 0..efc69feb4 --- /dev/null +++ b/arch/riscv/include/asm/kexec.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 FORTH-ICS/CARV + * Nick Kossifidis + */ + +#ifndef _RISCV_KEXEC_H +#define _RISCV_KEXEC_H + +/* Maximum physical address we can use pages from */ +#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL) + +/* Maximum address we can reach in physical address mode */ +#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL) + +/* Maximum address we can use for the control code buffer */ +#define KEXEC_CONTROL_MEMORY_LIMIT (-1UL) + +/* Reserve a page for the control code buffer */ +#define KEXEC_CONTROL_PAGE_SIZE 4096 + +#define KEXEC_ARCH KEXEC_ARCH_RISCV + +static inline void +crash_setup_regs(struct pt_regs *newregs, +struct pt_regs *oldregs) +{ + /* Dummy implementation for now */ +} + + +#define ARCH_HAS_KIMAGE_ARCH + +struct kimage_arch { + unsigned long fdt_addr; +}; + +const extern unsigned char riscv_kexec_relocate[]; +const extern unsigned int riscv_kexec_relocate_size; + +typedef void (*riscv_kexec_do_relocate)(unsigned long first_ind_entry, + unsigned long jump_addr, + unsigned long fdt_addr, + unsigned long hartid, + unsigned long va_pa_off); + +#endif diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 3dc0abde9..c2594018c 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -9,6 +9,10 @@ CFLAGS_REMOVE_patch.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_sbi.o= $(CC_FLAGS_FTRACE) endif +ifdef CONFIG_KEXEC +AFLAGS_kexec_relocate.o := -mcmodel=medany -mno-relax +endif + extra-y += head.o extra-y += vmlinux.lds @@ -54,6 +58,7 @@ obj-$(CONFIG_SMP) += cpu_ops_sbi.o endif obj-$(CONFIG_HOTPLUG_CPU) += cpu-hotplug.o obj-$(CONFIG_KGDB) += kgdb.o +obj-${CONFIG_KEXEC}+= kexec_relocate.o machine_kexec.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o diff --git a/arch/riscv/kernel/kexec_relocate.S b/arch/riscv/kernel/kexec_relocate.S new file mode 100644 index 0..616c20771 --- /dev/null +++ b/arch/riscv/kernel/kexec_relocate.S @@ -0,0 +1,156 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 FORTH-ICS/CARV + * Nick Kossifidis + */ + +#include/* For RISCV_* and REG_* macros */ +#include /* For PAGE_SHIFT */ +#include /* For SYM_* macros */ + +.section ".rodata"