Skip to content

Commit

Permalink
kexec: split kexec_load syscall from kexec core code
Browse files Browse the repository at this point in the history
There are two kexec load syscalls, kexec_load another and kexec_file_load.
 kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
split kexec_load syscall code to kernel/kexec.c.

And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.

The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
kexec_load syscall can bypass the checking.

Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.

Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
kexec_load syscall.

[[email protected]: coding-style fixes]
Signed-off-by: Dave Young <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Petr Tesarik <[email protected]>
Cc: Theodore Ts'o <[email protected]>
Cc: Josh Boyer <[email protected]>
Cc: David Howells <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
  • Loading branch information
daveyoung authored and torvalds committed Sep 10, 2015
1 parent a43cac0 commit 2965faa
Show file tree
Hide file tree
Showing 32 changed files with 1,560 additions and 1,527 deletions.
3 changes: 3 additions & 0 deletions arch/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,9 @@
# General architecture dependent options
#

config KEXEC_CORE
bool

config OPROFILE
tristate "OProfile system profiling"
depends on PROFILING
Expand Down
1 change: 1 addition & 0 deletions arch/arm/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -2020,6 +2020,7 @@ config KEXEC
bool "Kexec system call (EXPERIMENTAL)"
depends on (!SMP || PM_SLEEP_SMP)
depends on !CPU_V7M
select KEXEC_CORE
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
Expand Down
1 change: 1 addition & 0 deletions arch/ia64/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -518,6 +518,7 @@ source "drivers/sn/Kconfig"
config KEXEC
bool "kexec system call"
depends on !IA64_HP_SIM && (!SMP || HOTPLUG_CPU)
select KEXEC_CORE
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
Expand Down
1 change: 1 addition & 0 deletions arch/m68k/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -95,6 +95,7 @@ config MMU_SUN3
config KEXEC
bool "kexec system call"
depends on M68KCLASSIC
select KEXEC_CORE
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
Expand Down
1 change: 1 addition & 0 deletions arch/mips/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -2597,6 +2597,7 @@ source "kernel/Kconfig.preempt"

config KEXEC
bool "Kexec system call"
select KEXEC_CORE
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
Expand Down
1 change: 1 addition & 0 deletions arch/powerpc/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -420,6 +420,7 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
config KEXEC
bool "kexec system call"
depends on (PPC_BOOK3S || FSL_BOOKE || (44x && !SMP))
select KEXEC_CORE
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
Expand Down
1 change: 1 addition & 0 deletions arch/s390/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -48,6 +48,7 @@ config ARCH_SUPPORTS_DEBUG_PAGEALLOC

config KEXEC
def_bool y
select KEXEC_CORE

config AUDIT_ARCH
def_bool y
Expand Down
1 change: 1 addition & 0 deletions arch/sh/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -602,6 +602,7 @@ source kernel/Kconfig.hz
config KEXEC
bool "kexec system call (EXPERIMENTAL)"
depends on SUPERH32 && MMU
select KEXEC_CORE
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
Expand Down
1 change: 1 addition & 0 deletions arch/tile/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -205,6 +205,7 @@ source "kernel/Kconfig.hz"

config KEXEC
bool "kexec system call"
select KEXEC_CORE
---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
Expand Down
3 changes: 2 additions & 1 deletion arch/x86/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -1754,6 +1754,7 @@ source kernel/Kconfig.hz

config KEXEC
bool "kexec system call"
select KEXEC_CORE
---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
Expand All @@ -1770,8 +1771,8 @@ config KEXEC

config KEXEC_FILE
bool "kexec file based system call"
select KEXEC_CORE
select BUILD_BIN2C
depends on KEXEC
depends on X86_64
depends on CRYPTO=y
depends on CRYPTO_SHA256=y
Expand Down
2 changes: 1 addition & 1 deletion arch/x86/boot/header.S
Original file line number Diff line number Diff line change
Expand Up @@ -414,7 +414,7 @@ xloadflags:
# define XLF23 0
#endif

#if defined(CONFIG_X86_64) && defined(CONFIG_EFI) && defined(CONFIG_KEXEC)
#if defined(CONFIG_X86_64) && defined(CONFIG_EFI) && defined(CONFIG_KEXEC_CORE)
# define XLF4 XLF_EFI_KEXEC
#else
# define XLF4 0
Expand Down
2 changes: 1 addition & 1 deletion arch/x86/include/asm/kdebug.h
Original file line number Diff line number Diff line change
Expand Up @@ -29,7 +29,7 @@ extern void show_trace(struct task_struct *t, struct pt_regs *regs,
extern void __show_regs(struct pt_regs *regs, int all);
extern unsigned long oops_begin(void);
extern void oops_end(unsigned long, struct pt_regs *, int signr);
#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
extern int in_crash_kexec;
#else
/* no crash dump is ever in progress if no crash kernel can be kexec'd */
Expand Down
4 changes: 2 additions & 2 deletions arch/x86/kernel/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -71,8 +71,8 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
obj-$(CONFIG_X86_TSC) += trace_clock.o
obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o
obj-$(CONFIG_KEXEC) += relocate_kernel_$(BITS).o crash.o
obj-$(CONFIG_KEXEC_CORE) += machine_kexec_$(BITS).o
obj-$(CONFIG_KEXEC_CORE) += relocate_kernel_$(BITS).o crash.o
obj-$(CONFIG_KEXEC_FILE) += kexec-bzimage64.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o
obj-y += kprobes/
Expand Down
4 changes: 2 additions & 2 deletions arch/x86/kernel/kvmclock.c
Original file line number Diff line number Diff line change
Expand Up @@ -200,7 +200,7 @@ static void kvm_setup_secondary_clock(void)
* kind of shutdown from our side, we unregister the clock by writting anything
* that does not have the 'enable' bit set in the msr
*/
#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
static void kvm_crash_shutdown(struct pt_regs *regs)
{
native_write_msr(msr_kvm_system_time, 0, 0);
Expand Down Expand Up @@ -259,7 +259,7 @@ void __init kvmclock_init(void)
x86_platform.save_sched_clock_state = kvm_save_sched_clock_state;
x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state;
machine_ops.shutdown = kvm_shutdown;
#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
machine_ops.crash_shutdown = kvm_crash_shutdown;
#endif
kvm_get_preset_lpj();
Expand Down
4 changes: 2 additions & 2 deletions arch/x86/kernel/reboot.c
Original file line number Diff line number Diff line change
Expand Up @@ -673,7 +673,7 @@ struct machine_ops machine_ops = {
.emergency_restart = native_machine_emergency_restart,
.restart = native_machine_restart,
.halt = native_machine_halt,
#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
.crash_shutdown = native_machine_crash_shutdown,
#endif
};
Expand Down Expand Up @@ -703,7 +703,7 @@ void machine_halt(void)
machine_ops.halt();
}

#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
void machine_crash_shutdown(struct pt_regs *regs)
{
machine_ops.crash_shutdown(regs);
Expand Down
2 changes: 1 addition & 1 deletion arch/x86/kernel/setup.c
Original file line number Diff line number Diff line change
Expand Up @@ -478,7 +478,7 @@ static void __init memblock_x86_reserve_range_setup_data(void)
* --------- Crashkernel reservation ------------------------------
*/

#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE

/*
* Keep the crash kernel below this limit. On 32 bits earlier kernels
Expand Down
2 changes: 1 addition & 1 deletion arch/x86/kernel/vmlinux.lds.S
Original file line number Diff line number Diff line change
Expand Up @@ -364,7 +364,7 @@ INIT_PER_CPU(irq_stack_union);

#endif /* CONFIG_X86_32 */

#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
#include <asm/kexec.h>

. = ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
Expand Down
8 changes: 4 additions & 4 deletions arch/x86/kvm/vmx.c
Original file line number Diff line number Diff line change
Expand Up @@ -1264,7 +1264,7 @@ static void vmcs_load(struct vmcs *vmcs)
vmcs, phys_addr);
}

#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
/*
* This bitmap is used to indicate whether the vmclear
* operation is enabled on all cpus. All disabled by
Expand Down Expand Up @@ -1302,7 +1302,7 @@ static void crash_vmclear_local_loaded_vmcss(void)
#else
static inline void crash_enable_local_vmclear(int cpu) { }
static inline void crash_disable_local_vmclear(int cpu) { }
#endif /* CONFIG_KEXEC */
#endif /* CONFIG_KEXEC_CORE */

static void __loaded_vmcs_clear(void *arg)
{
Expand Down Expand Up @@ -10411,7 +10411,7 @@ static int __init vmx_init(void)
if (r)
return r;

#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
rcu_assign_pointer(crash_vmclear_loaded_vmcss,
crash_vmclear_local_loaded_vmcss);
#endif
Expand All @@ -10421,7 +10421,7 @@ static int __init vmx_init(void)

static void __exit vmx_exit(void)
{
#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL);
synchronize_rcu();
#endif
Expand Down
4 changes: 2 additions & 2 deletions arch/x86/platform/efi/efi.c
Original file line number Diff line number Diff line change
Expand Up @@ -650,7 +650,7 @@ static void __init get_systab_virt_addr(efi_memory_desc_t *md)

static void __init save_runtime_map(void)
{
#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
efi_memory_desc_t *md;
void *tmp, *p, *q = NULL;
int count = 0;
Expand Down Expand Up @@ -748,7 +748,7 @@ static void * __init efi_map_regions(int *count, int *pg_shift)

static void __init kexec_enter_virtual_mode(void)
{
#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
efi_memory_desc_t *md;
void *p;

Expand Down
6 changes: 3 additions & 3 deletions arch/x86/platform/uv/uv_nmi.c
Original file line number Diff line number Diff line change
Expand Up @@ -492,7 +492,7 @@ static void uv_nmi_touch_watchdogs(void)
touch_nmi_watchdog();
}

#if defined(CONFIG_KEXEC)
#if defined(CONFIG_KEXEC_CORE)
static atomic_t uv_nmi_kexec_failed;
static void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
{
Expand All @@ -519,13 +519,13 @@ static void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
uv_nmi_sync_exit(0);
}

#else /* !CONFIG_KEXEC */
#else /* !CONFIG_KEXEC_CORE */
static inline void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
{
if (master)
pr_err("UV: NMI kdump: KEXEC not supported in this kernel\n");
}
#endif /* !CONFIG_KEXEC */
#endif /* !CONFIG_KEXEC_CORE */

#ifdef CONFIG_KGDB
#ifdef CONFIG_KGDB_KDB
Expand Down
2 changes: 1 addition & 1 deletion drivers/firmware/efi/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -43,7 +43,7 @@ config EFI_VARS_PSTORE_DEFAULT_DISABLE

config EFI_RUNTIME_MAP
bool "Export efi runtime maps to sysfs"
depends on X86 && EFI && KEXEC
depends on X86 && EFI && KEXEC_CORE
default y
help
Export efi runtime memory maps to /sys/firmware/efi/runtime-map.
Expand Down
2 changes: 1 addition & 1 deletion drivers/pci/pci-driver.c
Original file line number Diff line number Diff line change
Expand Up @@ -467,7 +467,7 @@ static void pci_device_shutdown(struct device *dev)
pci_msi_shutdown(pci_dev);
pci_msix_shutdown(pci_dev);

#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
/*
* If this is a kexec reboot, turn off Bus Master bit on the
* device to tell it to not continue to do DMA. Don't touch
Expand Down
6 changes: 3 additions & 3 deletions include/linux/kexec.h
Original file line number Diff line number Diff line change
Expand Up @@ -16,7 +16,7 @@

#include <uapi/linux/kexec.h>

#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
#include <linux/list.h>
#include <linux/linkage.h>
#include <linux/compat.h>
Expand Down Expand Up @@ -329,13 +329,13 @@ int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
unsigned int relsec);

#else /* !CONFIG_KEXEC */
#else /* !CONFIG_KEXEC_CORE */
struct pt_regs;
struct task_struct;
static inline void crash_kexec(struct pt_regs *regs) { }
static inline int kexec_should_crash(struct task_struct *p) { return 0; }
#define kexec_in_progress false
#endif /* CONFIG_KEXEC */
#endif /* CONFIG_KEXEC_CORE */

#endif /* !defined(__ASSEBMLY__) */

Expand Down
4 changes: 2 additions & 2 deletions init/initramfs.c
Original file line number Diff line number Diff line change
Expand Up @@ -526,14 +526,14 @@ extern unsigned long __initramfs_size;

static void __init free_initrd(void)
{
#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
unsigned long crashk_end = (unsigned long)__va(crashk_res.end);
#endif
if (do_retain_initrd)
goto skip;

#ifdef CONFIG_KEXEC
#ifdef CONFIG_KEXEC_CORE
/*
* If the initrd region is overlapped with crashkernel reserved region,
* free only memory that is not part of crashkernel region.
Expand Down
1 change: 1 addition & 0 deletions kernel/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -49,6 +49,7 @@ obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_MODULE_SIG) += module_signing.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
obj-$(CONFIG_KEXEC_CORE) += kexec_core.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
Expand Down
2 changes: 1 addition & 1 deletion kernel/events/core.c
Original file line number Diff line number Diff line change
Expand Up @@ -9094,7 +9094,7 @@ static void perf_event_init_cpu(int cpu)
mutex_unlock(&swhash->hlist_mutex);
}

#if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC
#if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE
static void __perf_event_exit_context(void *__info)
{
struct remove_event re = { .detach_group = true };
Expand Down
Loading

0 comments on commit 2965faa

Please sign in to comment.