diff options
Diffstat (limited to 'arch/um/kernel/um_arch.c')
| -rw-r--r-- | arch/um/kernel/um_arch.c | 377 |
1 files changed, 260 insertions, 117 deletions
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c index 87df5e3acc26..e2b24e1ecfa6 100644 --- a/arch/um/kernel/um_arch.c +++ b/arch/um/kernel/um_arch.c @@ -1,19 +1,31 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) - * Licensed under the GPL */ +#include <linux/cpu.h> #include <linux/delay.h> #include <linux/init.h> #include <linux/mm.h> +#include <linux/ctype.h> #include <linux/module.h> +#include <linux/panic_notifier.h> #include <linux/seq_file.h> #include <linux/string.h> +#include <linux/string_choices.h> #include <linux/utsname.h> #include <linux/sched.h> -#include <asm/pgtable.h> +#include <linux/sched/task.h> +#include <linux/kmsg_dump.h> +#include <linux/suspend.h> +#include <linux/random.h> +#include <linux/smp-internal.h> + #include <asm/processor.h> +#include <asm/cpufeature.h> +#include <asm/sections.h> #include <asm/setup.h> +#include <asm/text-patching.h> #include <as-layout.h> #include <arch.h> #include <init.h> @@ -22,7 +34,10 @@ #include <mem_user.h> #include <os.h> -#define DEFAULT_COMMAND_LINE "root=98:0" +#include "um_arch.h" + +#define DEFAULT_COMMAND_LINE_ROOT "root=98:0" +#define DEFAULT_COMMAND_LINE_CONSOLE "console=tty0" /* Changed in add_arg and setup_arch, which run before SMP is started */ static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 }; @@ -30,7 +45,7 @@ static char __initdata command_line[COMMAND_LINE_SIZE] = { 0 }; static void __init add_arg(char *arg) { if (strlen(command_line) + strlen(arg) + 1 > COMMAND_LINE_SIZE) { - printf("add_arg: Too many command line arguments!\n"); + os_warn("add_arg: Too many command line arguments!\n"); exit(1); } if (strlen(command_line) > 0) @@ -40,43 +55,42 @@ static void __init add_arg(char *arg) /* * These fields are initialized at boot time and not changed. - * XXX This structure is used only in the non-SMP case. Maybe this - * should be moved to smp.c. */ struct cpuinfo_um boot_cpu_data = { .loops_per_jiffy = 0, - .ipi_pipe = { -1, -1 } + .cache_alignment = L1_CACHE_BYTES, + .x86_capability = { 0 } }; -union thread_union cpu0_irqstack - __attribute__((__section__(".data..init_irqstack"))) = - { INIT_THREAD_INFO(init_task) }; +EXPORT_SYMBOL(boot_cpu_data); -unsigned long thread_saved_pc(struct task_struct *task) -{ - /* FIXME: Need to look up userspace_pid by cpu */ - return os_process_pc(userspace_pid[0]); -} /* Changed in setup_arch, which is called in early boot */ static char host_info[(__NEW_UTS_LEN + 1) * 5]; static int show_cpuinfo(struct seq_file *m, void *v) { - int index = 0; + int i = 0; -#ifdef CONFIG_SMP - index = (struct cpuinfo_um *) v - cpu_data; - if (!cpu_online(index)) +#if IS_ENABLED(CONFIG_SMP) + i = (uintptr_t) v - 1; + if (!cpu_online(i)) return 0; #endif - seq_printf(m, "processor\t: %d\n", index); + seq_printf(m, "processor\t: %d\n", i); seq_printf(m, "vendor_id\t: User Mode Linux\n"); seq_printf(m, "model name\t: UML\n"); seq_printf(m, "mode\t\t: skas\n"); seq_printf(m, "host\t\t: %s\n", host_info); - seq_printf(m, "bogomips\t: %lu.%02lu\n\n", + seq_printf(m, "fpu\t\t: %s\n", str_yes_no(cpu_has(&boot_cpu_data, X86_FEATURE_FPU))); + seq_printf(m, "flags\t\t:"); + for (i = 0; i < 32*NCAPINTS; i++) + if (cpu_has(&boot_cpu_data, i) && (x86_cap_flags[i] != NULL)) + seq_printf(m, " %s", x86_cap_flags[i]); + seq_printf(m, "\n"); + seq_printf(m, "cache_alignment\t: %d\n", boot_cpu_data.cache_alignment); + seq_printf(m, "bogomips\t: %lu.%02lu\n", loops_per_jiffy/(500000/HZ), (loops_per_jiffy/(5000/HZ)) % 100); @@ -85,7 +99,9 @@ static int show_cpuinfo(struct seq_file *m, void *v) static void *c_start(struct seq_file *m, loff_t *pos) { - return *pos < NR_CPUS ? cpu_data + *pos : NULL; + if (*pos < nr_cpu_ids) + return (void *)(uintptr_t)(*pos + 1); + return NULL; } static void *c_next(struct seq_file *m, void *v, loff_t *pos) @@ -113,14 +129,13 @@ unsigned long uml_reserved; /* Also modified in mem_init */ unsigned long start_vm; unsigned long end_vm; -/* Set in uml_ncpus_setup */ -int ncpus = 1; - /* Set in early boot */ -static int have_root __initdata = 0; +static int have_root __initdata; +static int have_console __initdata; /* Set in uml_mem_setup and modified in linux_main */ -long long physmem_size = 32 * 1024 * 1024; +unsigned long long physmem_size = 64 * 1024 * 1024; +EXPORT_SYMBOL(physmem_size); static const char *usage_string = "User Mode Linux v%s\n" @@ -128,6 +143,7 @@ static const char *usage_string = static int __init uml_version_setup(char *line, int *add) { + /* Explicitly use printf() to show version in stdout */ printf("%s\n", init_utsname()->release); exit(0); @@ -154,42 +170,24 @@ __uml_setup("root=", uml_root_setup, " root=/dev/ubd5\n\n" ); -static int __init no_skas_debug_setup(char *line, int *add) +static int __init uml_console_setup(char *line, int *add) { - printf("'debug' is not necessary to gdb UML in skas mode - run \n"); - printf("'gdb linux'\n"); - + have_console = 1; return 0; } -__uml_setup("debug", no_skas_debug_setup, -"debug\n" -" this flag is not needed to run gdb on UML in skas mode\n\n" +__uml_setup("console=", uml_console_setup, +"console=<preferred console>\n" +" Specify the preferred console output driver\n\n" ); -#ifdef CONFIG_SMP -static int __init uml_ncpus_setup(char *line, int *add) -{ - if (!sscanf(line, "%d", &ncpus)) { - printf("Couldn't parse [%s]\n", line); - return -1; - } - - return 0; -} - -__uml_setup("ncpus=", uml_ncpus_setup, -"ncpus=<# of desired CPUs>\n" -" This tells an SMP kernel how many virtual processors to start.\n\n" -); -#endif - static int __init Usage(char *line, int *add) { const char **p; printf(usage_string, init_utsname()->release); p = &__uml_help_start; + /* Explicitly use printf() to show help in stdout */ while (p < &__uml_help_end) { printf("%s", *p); p++; @@ -233,42 +231,86 @@ static void __init uml_postsetup(void) static int panic_exit(struct notifier_block *self, unsigned long unused1, void *unused2) { + kmsg_dump(KMSG_DUMP_PANIC); bust_spinlocks(1); - show_regs(&(current->thread.regs)); bust_spinlocks(0); uml_exitcode = 1; os_dump_core(); - return 0; + + return NOTIFY_DONE; } static struct notifier_block panic_exit_notifier = { - .notifier_call = panic_exit, - .next = NULL, - .priority = 0 + .notifier_call = panic_exit, + .priority = INT_MAX - 1, /* run as 2nd notifier, won't return */ }; +void uml_finishsetup(void) +{ + atomic_notifier_chain_register(&panic_notifier_list, + &panic_exit_notifier); + + uml_postsetup(); + + new_thread_handler(); +} + /* Set during early boot */ +unsigned long stub_start; unsigned long task_size; EXPORT_SYMBOL(task_size); -unsigned long host_task_size; - unsigned long brk_start; -unsigned long end_iomem; -EXPORT_SYMBOL(end_iomem); #define MIN_VMALLOC (32 * 1024 * 1024) -extern char __binary_start; +static void __init parse_host_cpu_flags(char *line) +{ + int i; + for (i = 0; i < 32*NCAPINTS; i++) { + if ((x86_cap_flags[i] != NULL) && strstr(line, x86_cap_flags[i])) + set_cpu_cap(&boot_cpu_data, i); + } +} + +static void __init parse_cache_line(char *line) +{ + long res; + char *to_parse = strstr(line, ":"); + if (to_parse) { + to_parse++; + while (*to_parse != 0 && isspace(*to_parse)) { + to_parse++; + } + if (kstrtoul(to_parse, 10, &res) == 0 && is_power_of_2(res)) + boot_cpu_data.cache_alignment = res; + else + boot_cpu_data.cache_alignment = L1_CACHE_BYTES; + } +} -int __init linux_main(int argc, char **argv) +static unsigned long __init get_top_address(char **envp) +{ + unsigned long top_addr = (unsigned long) &top_addr; + int i; + + /* The earliest variable should be after the program name in ELF */ + for (i = 0; envp[i]; i++) { + if ((unsigned long) envp[i] > top_addr) + top_addr = (unsigned long) envp[i]; + } + + return PAGE_ALIGN(top_addr + 1); +} + +int __init linux_main(int argc, char **argv, char **envp) { unsigned long avail, diff; unsigned long virtmem_size, max_physmem; + unsigned long host_task_size; unsigned long stack; unsigned int i; int add; - char * mode; for (i = 1; i < argc; i++) { if ((i == 1) && (argv[i][0] == ' ')) @@ -279,26 +321,31 @@ int __init linux_main(int argc, char **argv) add_arg(argv[i]); } if (have_root == 0) - add_arg(DEFAULT_COMMAND_LINE); + add_arg(DEFAULT_COMMAND_LINE_ROOT); + + if (have_console == 0) + add_arg(DEFAULT_COMMAND_LINE_CONSOLE); + + host_task_size = get_top_address(envp); + /* reserve a few pages for the stubs */ + stub_start = host_task_size - STUB_SIZE; + host_task_size = stub_start; + + /* Limit TASK_SIZE to what is addressable by the page table */ + task_size = host_task_size; + if (task_size > (unsigned long long) PTRS_PER_PGD * PGDIR_SIZE) + task_size = PTRS_PER_PGD * PGDIR_SIZE; - host_task_size = os_get_top_address(); /* * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps * out */ - task_size = host_task_size & PGDIR_MASK; + task_size = task_size & PGDIR_MASK; /* OS sanity checks that need to happen before the kernel runs */ os_early_checks(); - can_do_skas(); - - if (proc_mm && ptrace_faultinfo) - mode = "SKAS3"; - else - mode = "SKAS0"; - - printf("UML running in %s mode\n", mode); + get_host_cpu_features(parse_host_cpu_flags, parse_cache_line); brk_start = (unsigned long) sbrk(0); @@ -307,54 +354,32 @@ int __init linux_main(int argc, char **argv) * so they actually get what they asked for. This should * add zero for non-exec shield users */ - - diff = UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end); + diff = PAGE_ALIGN(brk_start) - PAGE_ALIGN((unsigned long) &_end); if (diff > 1024 * 1024) { - printf("Adding %ld bytes to physical memory to account for " - "exec-shield gap\n", diff); - physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end); + os_info("Adding %ld bytes to physical memory to account for " + "exec-shield gap\n", diff); + physmem_size += diff; } - uml_physmem = (unsigned long) &__binary_start & PAGE_MASK; + uml_physmem = (unsigned long) __binary_start & PAGE_MASK; /* Reserve up to 4M after the current brk */ uml_reserved = ROUND_4M(brk_start) + (1 << 22); setup_machinename(init_utsname()->machine); - highmem = 0; - iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK; - max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC; - - /* - * Zones have to begin on a 1 << MAX_ORDER page boundary, - * so this makes sure that's true for highmem - */ - max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1); - if (physmem_size + iomem_size > max_physmem) { - highmem = physmem_size + iomem_size - max_physmem; - physmem_size -= highmem; -#ifndef CONFIG_HIGHMEM - highmem = 0; - printf("CONFIG_HIGHMEM not enabled - physical memory shrunk " - "to %Lu bytes\n", physmem_size); -#endif + physmem_size = PAGE_ALIGN(physmem_size); + max_physmem = TASK_SIZE - uml_physmem - MIN_VMALLOC; + if (physmem_size > max_physmem) { + physmem_size = max_physmem; + os_info("Physical memory size shrunk to %llu bytes\n", + physmem_size); } high_physmem = uml_physmem + physmem_size; - end_iomem = high_physmem + iomem_size; - high_memory = (void *) end_iomem; start_vm = VMALLOC_START; - setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem); - if (init_maps(physmem_size, iomem_size, highmem)) { - printf("Failed to allocate mem_map for %Lu bytes of physical " - "memory and %Lu bytes of highmem\n", physmem_size, - highmem); - exit(1); - } - virtmem_size = physmem_size; stack = (unsigned long) argv; stack &= ~(1024 * 1024 - 1); @@ -364,39 +389,70 @@ int __init linux_main(int argc, char **argv) end_vm = start_vm + virtmem_size; if (virtmem_size < physmem_size) - printf("Kernel virtual memory size shrunk to %lu bytes\n", - virtmem_size); + os_info("Kernel virtual memory size shrunk to %lu bytes\n", + virtmem_size); - atomic_notifier_chain_register(&panic_notifier_list, - &panic_exit_notifier); - - uml_postsetup(); + arch_task_struct_size = sizeof(struct task_struct) + host_fp_size; - stack_protections((unsigned long) &init_thread_info); os_flush_stdout(); return start_uml(); } +int __init __weak read_initrd(void) +{ + return 0; +} + void __init setup_arch(char **cmdline_p) { + u8 rng_seed[32]; + + stack_protections((unsigned long) init_task.stack); + setup_physmem(uml_physmem, uml_reserved, physmem_size); + uml_dtb_init(); + read_initrd(); + paging_init(); - strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); + strscpy(boot_command_line, command_line, COMMAND_LINE_SIZE); *cmdline_p = command_line; setup_hostinfo(host_info, sizeof host_info); + prefill_possible_map(); + + if (os_getrandom(rng_seed, sizeof(rng_seed), 0) == sizeof(rng_seed)) { + add_bootloader_randomness(rng_seed, sizeof(rng_seed)); + memzero_explicit(rng_seed, sizeof(rng_seed)); + } } -void __init check_bugs(void) +void __init arch_cpu_finalize_init(void) { arch_check_bugs(); os_check_bugs(); } +void apply_seal_endbr(s32 *start, s32 *end) +{ +} + +void apply_retpolines(s32 *start, s32 *end) +{ +} + +void apply_returns(s32 *start, s32 *end) +{ +} + +void apply_fineibt(s32 *start_retpoline, s32 *end_retpoline, + s32 *start_cfi, s32 *end_cfi) +{ +} + void apply_alternatives(struct alt_instr *start, struct alt_instr *end) { } -#ifdef CONFIG_SMP +#if IS_ENABLED(CONFIG_SMP) void alternatives_smp_module_add(struct module *mod, char *name, void *locks, void *locks_end, void *text, void *text_end) @@ -407,3 +463,90 @@ void alternatives_smp_module_del(struct module *mod) { } #endif + +void *text_poke(void *addr, const void *opcode, size_t len) +{ + /* + * In UML, the only reference to this function is in + * apply_relocate_add(), which shouldn't ever actually call this + * because UML doesn't have live patching. + */ + WARN_ON(1); + + return memcpy(addr, opcode, len); +} + +void *text_poke_copy(void *addr, const void *opcode, size_t len) +{ + return text_poke(addr, opcode, len); +} + +void smp_text_poke_sync_each_cpu(void) +{ +} + +void uml_pm_wake(void) +{ + pm_system_wakeup(); +} + +#ifdef CONFIG_PM_SLEEP +static int um_suspend_valid(suspend_state_t state) +{ + return state == PM_SUSPEND_MEM; +} + +static int um_suspend_prepare(void) +{ + um_irqs_suspend(); + return 0; +} + +static int um_suspend_enter(suspend_state_t state) +{ + if (WARN_ON(state != PM_SUSPEND_MEM)) + return -EINVAL; + + /* + * This is identical to the idle sleep, but we've just + * (during suspend) turned off all interrupt sources + * except for the ones we want, so now we can only wake + * up on something we actually want to wake up on. All + * timing has also been suspended. + */ + um_idle_sleep(); + return 0; +} + +static void um_suspend_finish(void) +{ + um_irqs_resume(); +} + +const struct platform_suspend_ops um_suspend_ops = { + .valid = um_suspend_valid, + .prepare = um_suspend_prepare, + .enter = um_suspend_enter, + .finish = um_suspend_finish, +}; + +static int init_pm_wake_signal(void) +{ + /* + * In external time-travel mode we can't use signals to wake up + * since that would mess with the scheduling. We'll have to do + * some additional work to support wakeup on virtio devices or + * similar, perhaps implementing a fake RTC controller that can + * trigger wakeup (and request the appropriate scheduling from + * the external scheduler when going to suspend.) + */ + if (time_travel_mode != TT_MODE_EXTERNAL) + register_pm_wake_signal(); + + suspend_set_ops(&um_suspend_ops); + + return 0; +} + +late_initcall(init_pm_wake_signal); +#endif |